Technically, Why Does MV Get a Bad Rap?

[epluribus]

We just touched on this in another thread, but I've been intrigued by this for quite some time--does adding an MV to a circuit do something inherently "bad" to it? Does it degrade the signal or foul up gain stage coupling or something?

Always suspected that a switch will eat some signal compared to a short and solid piece of wire. Same with putting a channel switch someplace in the circuit, or using a variable resistor instead of a fixed resistor. But maybe not, at least in some cases...

On the other thread in question, several people mentioned that same-model amps with MV usually aren't completely same-model; they usually have changes elsewhere in the circuit, hence the notion that MV colors tone. I sorta got the idea that maybe adding the MV function, properly done, doesn't hurt a thing. Not sure, so now I'm askin...

Opinions?

Thanks, as always.

--Ray

[jlummaa]

There are several ways to make a MV. They sound different from each other. Some like it this way and some swear that the other one is the best one. Some MV designs will basically remove themselves from the circuit when maxed, some others don't. Then some don't like them at all because you lose the power amp distortion/compression (like me). In theory, anything you add to the circuit will degrade the signal a bit but then again you have to admit how much a guitar amp will degrade you guitar's original signal after all, guitar amps are very very lo-fi in that sense, they are distortion generators.

So we end up with the conclusion (as with everything else) that it's matter of taste.

[SatelliteAmps]

The main reason I don't like them is because too many people have monster truck issues (the most polite comparision I could come up with). I see a lot of people purchasing amplifiers that are way bigger than they need, and then always using a Master Volume to tame them to apartment level. If most of these people got a good smaller amp, they would actually get a better range of tones.

I disagree that amps are just distortion generators. That's a whole discussion unto itself though.

[John Phillips]

The main reason I don't like them is because too many people have monster truck issues (the most polite comparision I could come up with). I see a lot of people purchasing amplifiers that are way bigger than they need, and then always using a Master Volume to tame them to apartment level. If most of these people got a good smaller amp, they would actually get a better range of tones.I don't agree. Using a big amp with flexible controls and a good MV gets you a better range of tones. I don't see how there can be any argument about that - the big MV amp will always be capable of a wider range of sounds precisely because the volume and distortion can be largely independent - it will go louder clean than a small amp, and much quieter distorted. With a non-MV amp, they're directly linked and you will not be able to get any distortion at apartment volume (not unless you're talking about a 1W-range amp, or use an attenuator).

I totally agree that amps are not just distortion generators, and I play clean most of the time. But tonally (not counting distortion) the bigger amp will very likely be capable of a wider range of sounds too, since it will probably be capable of more bass and possibly more treble, even at the same volume.

I'm not saying the quality of sound will necessarily be better - although I think it's a complete myth that MV amps always sound less good, even when played quietly - but for flexibility, you absolutely need to separate volume from tone and distortion.

I don't like my big MV amp beause I have 'monster truck issues' :) - in fact, for years I would never even use a 2x12" amp because I thought it was unnecessarily big, and certainly not a stack (much too 'rock' ;))... I prefered to hit hard with a small amp - I like it because it sounds better than the smaller amps I've used (at any volume) and means I don't need to own or carry more than one amp for any size of venue. By 'better', I mean bigger, deeper, more powerful and dynamic. If you like smooth, more compressed tones where your touch affects the tone rather than the volume the opposite may be true.


Technically, one reason that a lot of MV amps can sound 'fizzy' or 'buzzy' at lower volumes is because the power stage is capable of cleanly and equally reproducing all the frequencies generated by the preamp, and distortion contains dispropotionately more highs (and lows to some extent) than clean. In a non-MV amp, by the time the power stage distorts, it will also be heavily loading the power supply and probably the OT - and even the speakers - which produces compression and a narrowing of the bandwidth into the midrange, so it helps smooth out the peaks and chop off the high 'fizz' and low 'buzz' frequencies.

So in fact, it's not that MVs 'degrade' the sound - it's actually power stage distortion and compression that degrades the sound, but in a way that sounds pleasing :D.

Not all MVs sound the same though, depending on exactly where they are in the circuit.

[jlummaa]

I apologise my rather rude characterization of guitar amp being distortion generator. I explain a little bit my point of view.

My claim is based on the fact that guitar amp alters the original guitar tone, it distorts the original. Well, this is the thing most of us want (including me) and that is why we don't use hifi amps with 0,01 % THD let alone the hifi speakers.

Now back to MV discussion :D

[teleamp]

I prefer a clean/gritty amp and don't use effects, so I prefer non-mv amps. All the mv amps I have played, I always kept the MV maxed. If I can't get the amp into its sweet spot because of volume, I switch to a lower wattage amp.

MikeY

[Swarty]

I think it is mostly a snob thing. But I guess I'm a snob as I prefer to size the amp to the job.

[hasserl]

I've got amps from just a couple of watts output into an 8" speaker to over a hundred into 4 x 12" speakers, and lot's of different combinations in between. I still find a MV makes an amp much more versatile, allowing you to tune it to the situation at hand. You can always bring a larger amp down in volume with the MV, you can't always make a smaller amp louder. But often, even the "small" amp is too loud. I remember being told to turn down my Princeton Reverb once at a bar. Well, maybe that was just due to my playing ability. And my PR is actually close to a DR in output. But still, that's not a lot of amp for a bar. What are you going to take to a gig that's less than that? I tend to take an attenuator with me now with my non MV amps, just in case.

[epluribus]

Such an intriguing issue, so much to be gained (no pun intended) by really understanding it.

I'm a firm believer in MV, but least because I want to fit a loud amp into a quiet venue. My experience jibes with what Satellite mentioned, that most people use 'em for attenuation, not gain-shaping, which is a valid technique as long as you understand what's happening. (BTW, I prefer attenuators in a pinch, but much prefer to match the amp to the room for starters. )

What floats my boat about MV is that it allows you far greater control of the gain structure at the various stages of the amp--the user gets to decide which gain stages saturate the most, and at what rates. Not only do volume and distortion become independent as John said, but preamp and poweramp distortion become independent as well, depending on the MV's location in the circuit. Further, even for playing basically clean, gain structure is huge for optimizing and shaping the voice of the amp, at least IMHO. It's like being able to rewire the amp on the fly. (AAMOF the MV amp I'm building right now is a single-ended EL84 banty rooster, so I guess the issue ain't exactly about big cajones volume. :))

As for whether MV allows you to use a big amp to be a "better" equivalent of a small one, I'd refer to our recent threads about the electrical differences between big iron and small--IMHO, it's tons more than just volume and freq response. Certainly if what you want is the dynamics and component interactions in the rig that big iron gives you, small gear won't function the same way. But the reason I expanded here a bit is because this is a valid issue, but not really related to what costs MV impose on a circuit. When we talk about big vs. small, IMHO that's more about a choice of instruments, as opposed to MV being a tool to shape the instrument of choice. Not to nitpick, and my mea culpas if I have, but I think this is a great point you guys bring up, and a distinction that, if current threads are any indication, a lot of folks don't think about. Certainly I didn't distinguish enough before exploring those threads.

BTW, hasserl, Swarty, and teleamp, I gather this is a question you guys have each addressed in your thinking on your way to arriving at your decisions about how to voice the instrument. Cool, this is something else that's rasslin' around in my little brain.

Technically, one reason that a lot of MV amps can sound 'fizzy' or 'buzzy' at lower volumes is because the power stage is capable of cleanly and equally reproducing all the frequencies generated by the preamp, and distortion contains dispropotionately more highs (and lows to some extent) than clean. In a non-MV amp, by the time the power stage distorts, it will also be heavily loading the power supply and probably the OT - and even the speakers - which produces compression and a narrowing of the bandwidth into the midrange, so it helps smooth out the peaks and chop off the high 'fizz' and low 'buzz' frequencies.

Boy, for where I'm headed, this is a terrifically insightful point. Presuming I include gain structuring functions in my circuit, like MV, this certainly has to enter my thinking for circuit design as well as using the amp while playing. It begs a great design question: presuming I've twiddled my knobs to structure my amp for running the front end hard and the back clean, should I find a way to progressively correct for the disproportionate freq response in sum total of the circuit? Or is it better to entrust that to the tone stack operator? Self-compensation may or may not be a good way to solve for the problem above.

Big thanks for bringing this up--sorta like I knew it but never connected the dots that way.

Kinda long probably, but this part of the discussion hits the nail on the head, IMHO. We've identified one impact of using MV that likely gets a bad rap cuz the MV isn't exactly "the same," but if we become aware of the "problem" as designers and users, we can at least compensate for it at worst, or treat it as another tool to shape tone at best. I like best. :)


On the issue of where to put MV in a circuit, that's just plain huge IMHO. When I got my DR II and started learning the marvels of all this, I ended up mapping out where each pot is, and which gain stages they fall between. For an amp with essentially three MV-ish functions, that's a crucially important point, and for the reasons John mentions. (Four MV-ish functions if you count the tone stack, and five if you use clean boost, change guitar volume, or switch guitars at all.) It's all good that the DR II's chameleon functions nearly outmatch the flexibility of my CyberTwin, (Really, it's amazing what a well-designed analog circuit can do.) but the ability to truly zero in on just the right sound to suit the song and the guitar is ten times cooler.

So all these immensely useful things being ripe for the pickin's, and exceedingly tempting to pick 'em all, the question remains: What does it cost me each time I stick yet another MV or switch function somewhere in the circuit? Power amp response is certainly one big set of issues, again my thanks for the detail on that. Unless everybody is OD'in' and makin' for the beer tap, :messedup what else happens when you add switching or pots to an otherwise hard-wired circuit?

:BEER

--Dorothy

__________

(Wayward tour bus in northern Indiana) Gee Kansas, I don't think we're in Toto anymore.

[SatelliteAmps]

I don't agree. Using a big amp with flexible controls and a good MV gets you a better range of tones.


I think my point came across incorrectly. My point is about people that NEVER have an oppertunity turn their amp up, and have to always keep the MV on 1. Always having the MV set so low, will limit the scope of an amplfifiers tone.

In my experience and opinion this happens a lot in real life. People in these situations are almost always served better by getting a smaller amp, so they can use the features as you described them.

I do not think everyone who has a MV amp has a monster truck thing, but there are a lot of people out there who buy huge amps that will never be able to use the amp in a way that sounds even part way decent. That is the most bothersome part of MV's in my opinion, rather than how they may or may not affect tone.

[jay42]

Sounds like you have the idea. In the simplest terms, in the days of yore, techs put MVs into amps that weren't meant to have distorting pre-amps. Most unimpressive. The next step was double up the gain somewhere by adding a stage. MKI Boogie...eventually the JCM800 2203/2204 and so on. Now you can choose from Dumble variants, CAE's, Rivera's, et al.

[TheAmpNerd]

I"ll through in my $.02


There I did it. I might comment later, but college football is taking
it's tole on my internet time.

[rockon1]

I think my point came across incorrectly. My point is about people that NEVER have an oppertunity turn their amp up, and have to always keep the MV on 1. Always having the MV set so low, will limit the scope of an amplfifiers tone.


I'd say thats a bit exaggerated. Even when I was using a 100 watt head my master was at least at 3 or 4. That said I play mostly rock and hard rock covers and have downsized to 30-50 watt combo's and heads.( 50 watts seems optimal.) They get pushed considerably harder but still not into saturation which for me is a good thing.Nothing worse sounding to my ears than a MV amp being driven too hard. Mushy,compressed,undefined. I like having headroom even playing dirty. It just sounds better to me.:) Bob

[SatelliteAmps]

I'd say thats a bit exaggerated. Even when I was using a 100 watt head my master was at least at 3 or 4. That said I play mostly rock and hard rock covers and have downsized to 30-50 watt combo's and heads.( 50 watts seems optimal.) They get pushed considerably harder but still not into saturation which for me is a good thing.Nothing worse sounding to my ears than a MV amp being driven too hard. Mushy,compressed,undefined. I like having headroom even playing dirty. It just sounds better to me.:) Bob

Might be a bit extreme in the example, but I think you understand my point.

[epluribus]

Just ran across another issue that came up in the PA world--generally speaking, anytime you add a component (like a pot) to a solid piece of wire, it's often said that you're going to lose some of the highs. I take a different approach to this concept, preferring to think of it as a loss of the smallest-amplitude details in the signal that, thanks to the inserted component, fall below the "treshold of hearing" of the amp, and those details can't be put back once lost. A small change, perhaps, but amps have a way of making small things bigger.

I have always had a hunch this is behind the bad press about MV, channel switching, etc. Once you add a switch to a solid piece of wire, you'll give up a tiny bit of signal without a corresponding loss in the noise floor. Lower S/N, at least, but I think the real loss is the details that distinguish a living breathing player from a final recording.

Trouble is, my hunch is just that...a hunch. No real science to speak of, nor have I read any. Further opinions?

--Ray

[SatelliteAmps]

I would't think it is enough to make a noticeable difference, considering how many components are already in the circuit, adding a pot or switch to the circuit wouldn't make a huge difference in signal strength, or high frequency response.

[hasserl]

Just ran across another issue that came up in the PA world--generally speaking, anytime you add a component (like a pot) to a solid piece of wire, it's often said that you're going to lose some of the highs. I take a different approach to this concept, preferring to think of it as a loss of the smallest-amplitude details in the signal that, thanks to the inserted component, fall below the "treshold of hearing" of the amp, and those details can't be put back once lost. A small change, perhaps, but amps have a way of making small things bigger.

I have always had a hunch this is behind the bad press about MV, channel switching, etc. Once you add a switch to a solid piece of wire, you'll give up a tiny bit of signal without a corresponding loss in the noise floor. Lower S/N, at least, but I think the real loss is the details that distinguish a living breathing player from a final recording.

Trouble is, my hunch is just that...a hunch. No real science to speak of, nor have I read any. Further opinions?

--Ray

I think there is validity to this POV. I'm a firm believer in the KISS principle. But I would also say that this is more important in the earliest stages on the pre-amp, and less important in the later stages of the pre-amp or in the power amp.

But like you this is just a hunch on my part.

[epluribus]

I think there is validity to this POV. I'm a firm believer in the KISS principle. But I would also say that this is more important in the earliest stages on the pre-amp, and less important in the later stages of the pre-amp or in the power amp.

But like you this is just a hunch on my part.

Hey Hasserl, 'preciate the words. On signal integrity being most important early in a signal path, that's a great point. (I last read this in Dave Hunter's book.) Glad you brought it up, as I was leaving it out for some bizarre reason. :rolleyes:

As for that notion being scientific, AAMOF besides Hunter, I've read it in scads of other tech writing, particularly in the PA world. Makes sense to me too---if a signal is going to go through a bunch of gain stages, the earlier there's an undesirable addition, (or more accurately, a dip in S/N) the more amplification it gets before it hits the speakers. Conversely, usually you simply have to attenuate something in your signal, and doing it as late in the chain as possible allows you to best get away with it, S/N-wise. I always figured that's why the fader comes last on a mixer channel strip.

In our case with MV, it's kinda nice that MV just so happens to come so close to last in the signal path of an amp--at least it's in a least-damage location. :) Even so, it sure gets a lot of bad press, some of it seemignly legit from an S/N standpoint. But I still ain't convinced it hasn't been done very successfully someplace...

Maybe the way to approach this subject is with a question: Anywhere in the audio world, has anyone ever successfully built a circuit approaching the signal integrity of a Tweed amp, and the gain structure control of an MV amp?

--Ray

[Mapleneck]

I think there are too many playing styles to declare that MV is better than non-MV or visa-versa. If I played clean mostly, Like John Phillips says he does, I might like a MV amp. He needs that headroom to stay clean, and he is then free to adjust upward as needed - at least to a point.

Where I have a problem in talking about 'real world situations vs MV' is that at some point this issue bumps into the discussion on stage volume (at least in my mind). When do you really need 50+ watts with or without a MV with todays PA's? Granted I don't play cleanly very often, though I am not a rocker by any stretch. I love the growl of a good tweed amp. But I can literally play my Tweed Deluxe anywhere I want to play today. It is plenty flexible at any venue, even if I want to play clean, because I let the PA do all the work. People are usually grateful for the very manageable stage volume. In fact I am thinking about buying a Vicky 5112. I played one the other day and it was plenty loud, given a good PA, for anything I would ever do (I actually use an attenuator with my Deluxe most of the time).

So I say a MV may or may not work for your style, who cares so long as you are getting the sound you like out of your amp. But where the heck are any of you realistically using 50+ watts? Why are you still letting your amp do most of the work, when the PA can balance the sound to the audience so much better? I know it is fun to play loud now and again, but really PA's have advanced to a point today, that the electric guitar amp is really just a tone generator, not a volume generator - ok it is a little bit of a volume generator, but it needn't be any more so than the the soundboard/box on an acoustic guitar. Your lead singer shows up with nothing but his/her voice and the PA makes him/her plenty loud. That 5 watt Vicky was too loud to talk over, so the human voice isn't as loud as a 5 watt amp (give or take). Yet singers perform in arenas everyday before 10's of thousands of screaming fans, with nothing more than that small human voice.

I am inclined to believe that in the real world, 100watt amps are dinosours, and 50 watters are at the very least Mastadons - with or without MV's. If you can get loud enough to get your clean signal at a level to which you can monitor nicely and get into the mix well, then you are loud enough. If it takes a MV to do that, that is fine. If you have an amp that will do it without a MV, that is fine too. But for crying out loud, that is as loud as you have to be, and everyone is the better for it. Everytime I go see a band and the guitar player is blasting through too large/loud an amp, the overall band sound is generally awful. Out of balance, and awash in bass lower mid mush. Get the right amp for the job, put the overall band sound first and foremost, and sit back and accept all the compliments you will be getting, since more people will be hearing your playing clearly. That's my opinion and I am sticking to it (unless someone makes a really good counter point and makes me feel stupid).

edit: I know all the arguments about having to "move air" to get certain tones, but I still argue the audience doesn't hear what you think they are hearing when you playing too loud and you are presented badly in the mix as a result. YMMV.

[justonwo]

Thanks in large part to guitar forums, I've spent the good part of the last 3 or 4 years looking at NMV amps. Frankly, I like MV better. They are more versatile. And a MV with an attenuator - THAT is a very versatile amp.

[hasserl]

When do you really need 50+ watts with or without a MV with todays PA's?I play a lot of private parties and small bars/clubs. The amps are never mic'd, the PA is only used for the vocals and occasionally they stick a mic in front of the bass drum. In these situations the amp is definitely the volume generator as well as the tone generator.

a MV with an attenuator - THAT is a very versatile ampI agree! But if I could only have one I'd choose the MV for its simplicity and convienence.

[Mickey Shane]

I've noticed, that if you take a MV amp and turn the MV up to max, it won't idle quietly. It's almost as if MV amps are designed where the big knob should be kept under 8.

I find this to be annoying. A good MV amp should idle quietly with the MV on 10 and the ch. vol. down low.

Pet peeve of mine.

[John Phillips]

In our case with MV, it's kinda nice that MV just so happens to come so close to last in the signal path of an amp--at least it's in a least-damage location. :) Even so, it sure gets a lot of bad press, some of it seemignly legit from an S/N standpoint.No, it's the other way round - from a S/N standpoint, a MV is a good thing. Try comparing an MV amp (a Fender SF Twin is a good example) with the MV up full and everything controlled from the preamp volume, vs the MV lower and the preamp volume up a bit - not even to create distortion, just to maximise the signal level earlier in the amp. Running the MV lower helps remove noise.

I think there are too many playing styles to declare that MV is better than non-MV or visa-versa. If I played clean mostly, Like John Phillips says he does, I might like a MV amp. He needs that headroom to stay clean, and he is then free to adjust upward as needed - at least to a point.

Where I have a problem in talking about 'real world situations vs MV' is that at some point this issue bumps into the discussion on stage volume (at least in my mind). When do you really need 50+ watts with or without a MV with todays PA's? Granted I don't play cleanly very often, though I am not a rocker by any stretch. I love the growl of a good tweed amp. But I can literally play my Tweed Deluxe anywhere I want to play today. It is plenty flexible at any venue, even if I want to play clean, because I let the PA do all the work. People are usually grateful for the very manageable stage volume. In fact I am thinking about buying a Vicky 5112. I played one the other day and it was plenty loud, given a good PA, for anything I would ever do (I actually use an attenuator with my Deluxe most of the time).

So I say a MV may or may not work for your style, who cares so long as you are getting the sound you like out of your amp. But where the heck are any of you realistically using 50+ watts? Why are you still letting your amp do most of the work, when the PA can balance the sound to the audience so much better? I know it is fun to play loud now and again, but really PA's have advanced to a point today, that the electric guitar amp is really just a tone generator, not a volume generator - ok it is a little bit of a volume generator, but it needn't be any more so than the the soundboard/box on an acoustic guitar. Your lead singer shows up with nothing but his/her voice and the PA makes him/her plenty loud. That 5 watt Vicky was too loud to talk over, so the human voice isn't as loud as a 5 watt amp (give or take). Yet singers perform in arenas everyday before 10's of thousands of screaming fans, with nothing more than that small human voice.

I am inclined to believe that in the real world, 100watt amps are dinosours, and 50 watters are at the very least Mastadons - with or without MV's. If you can get loud enough to get your clean signal at a level to which you can monitor nicely and get into the mix well, then you are loud enough. If it takes a MV to do that, that is fine. If you have an amp that will do it without a MV, that is fine too. But for crying out loud, that is as loud as you have to be, and everyone is the better for it. Everytime I go see a band and the guitar player is blasting through too large/loud an amp, the overall band sound is generally awful. Out of balance, and awash in bass lower mid mush. Get the right amp for the job, put the overall band sound first and foremost, and sit back and accept all the compliments you will be getting, since more people will be hearing your playing clearly. That's my opinion and I am sticking to it (unless someone makes a really good counter point and makes me feel stupid).

edit: I know all the arguments about having to "move air" to get certain tones, but I still argue the audience doesn't hear what you think they are hearing when you playing too loud and you are presented badly in the mix as a result. YMMV.I think you're making the mistake of confusing available power with volume - nothing personal or trying to make you feel stupid, most of the people that post here seem to not understand this either. You do not need to turn your amp up all the way. Just because you have 100W doesn't mean you need to use it all. You don't 'need' 100, or even 50, watts for most gigs - but the tone is better from the big amps, and the only way to reconcile the two if you do want to use the amp for distortion is with a good MV. (Or attenuator.) I certainly don't use my 100W amp at anything like it's full power - I'm quite sure it doesn't go over about 15W in the sort of gigs I play, exactly because I tried using a 15W/30W amp, and it was just loud enough on the 15W setting. But it broke up in ways I didn't want sometimes, and just didn't sound as full and good. On the 30W setting I couldn't get breakup when I did want it (no MV)... so I don't actually need more than 30W, even though I do want clean headroom - but still the 100W amp sounds better.

I care about the band's sound far more than my own tone BTW - and I can categorically say that it's better with what I'm using now than what I had before. The big amp is the right amp for the job. It doesn't matter in any way to me that it's far more powerful than I 'need'. If anything, it actually fills the space much better than the smaller amps did, at slightly lower volume, and if anything might be quieter in the direct line, so the overall mix is better.

And if I do ever need to play on a really big stage or outdoors - where even the 50W amp I had before sounded boxy, although it was technically loud enough - no problem, just turn up. I don't need to own more than one amp. (I've still got the 15/30W, just because it sounds so nice and it's easier to carry :).)

Just FWIW, a 100W amp run at 15W is almost certain to be more reliable than a 15W amp cranked right up too.

I've noticed, that if you take a MV amp and turn the MV up to max, it won't idle quietly. It's almost as if MV amps are designed where the big knob should be kept under 8.

I find this to be annoying. A good MV amp should idle quietly with the MV on 10 and the ch. vol. down low.

Pet peeve of mine.But if you limited the range by making 10 where 8 is now, someone might find that they really wanted the setting on 8.5, and now they can't get to it. A little more range than you really need is a good thing.

You do not have to turn it up all the way just because it goes that far.

[Mapleneck]

I think you're making the mistake of confusing available power with volume - nothing personal or trying to make you feel stupid, most of the people that post here seem to not understand this either. You do not need to turn your amp up all the way. Just because you have 100W doesn't mean you need to use it all. You don't 'need' 100, or even 50, watts for most gigs - but the tone is better from the big amps, and the only way to reconcile the two if you do want to use the amp for distortion is with a good MV. (Or attenuator.) I certainly don't use my 100W amp at anything like it's full power - I'm quite sure it doesn't go over about 15W in the sort of gigs I play, exactly because I tried using a 15W/30W amp, and it was just loud enough on the 15W setting. But it broke up in ways I didn't want sometimes, and just didn't sound as full and good. On the 30W setting I couldn't get breakup when I did want it (no MV)... so I don't actually need more than 30W, even though I do want clean headroom - but still the 100W amp sounds better.

I care about the band's sound far more than my own tone BTW - and I can categorically say that it's better with what I'm using now than what I had before. The big amp is the right amp for the job. It doesn't matter in any way to me that it's far more powerful than I 'need'. If anything, it actually fills the space much better than the smaller amps did, at slightly lower volume, and if anything might be quieter in the direct line, so the overall mix is better.

And if I do ever need to play on a really big stage or outdoors - where even the 50W amp I had before sounded boxy, although it was technically loud enough - no problem, just turn up. I don't need to own more than one amp. (I've still got the 15/30W, just because it sounds so nice and it's easier to carry :).)

Just FWIW, a 100W amp run at 15W is almost certain to be more reliable than a 15W amp cranked right up too.



I don't think I was mistaking available power vs volume, at least not intentionally. I am very aware of the difference most of the time. Actually, though I am not near as eloquent, I think we were saying close to the same thing. If you play clean you need the power for the overhead, not necessarily the volume. And if you need (or like the sound of) a MV amp, or any larger amp to get your tone, that is great. But even using only 15 of your 100 available watts, you are must be playing a lot louder than me (before the PA). My Tweed Deluxe barely makes 12 watts on a good day, I only turn it about half up, and I use an attenuator with it. And I get beautiful cleans IMO (by rolling the guitar back). It doesn't sound like a big amp I'm sure, but I love it. Without the PA you wouldn't hear it well above the drums, if at all. But that is the marvel of modern PAs. And I love the lower stage volume. At 15 watts, you would get asked to turn it down a little at most places I play (I do "occasionally" play larger places, but not often).

Now the point was made that some don't have PA's at their disposal, and I suppose that happens sometimes. I haven't had to do that in quite a while. Even cheap PA's these days, have enough channels to mic an extra guitar amp. I mean, if you have a singer, you have a PA right?

And whether or not the tone is better from larger amps is subjective. I played a tele through that Vicky 5112 (at a whopping 5 watts), and have NEVER in 35 odd years of playing guitar heard more pleasing tone. Over that 35 years I have owned, played, and unfortunately lugged around, a LOT of 100 watt amps, MV and non-MV. The biggest thing I have now is a 35 watt Vibrolux Reverb, and it is too big, heavy, and loud for anything I do now. I just don't get the need for all the power, when there is a couple thousand watts in the pa?

Actually now that I think about it my beef was a little off topic. I apologize for changing the topic a little. But whenever people start talking about "needing" 50 watts or more, even if the topic is MV's, it just riles me slightly (ok...very slightly). I just think many, especially people who don't play cleanly, and hence don't need the overhead, try to drive the volume too high on stage with their amps, whether they have a MV at their disposal or not. And the resulting tone, IMO, is never optimal as a result.

[epluribus]

No, it's the other way round - from a S/N standpoint, a MV is a good thing. Try comparing an MV amp (a Fender SF Twin is a good example) with the MV up full and everything controlled from the preamp volume, vs the MV lower and the preamp volume up a bit - not even to create distortion, just to maximise the signal level earlier in the amp. Running the MV lower helps remove noise.

Hey John.

Agreed, that's an important point when you're actually using the knobs to set levels along your signal path to reduce noise and maximize signal. That's certainly what you do when setting up gain structure in a PA system, and IMHO it applies to gain structuring a guitar amp as well. It's definitely true of my DR II.

My thinking here, however, has to do with the design and construction of the circuit, as opposed to its operation once built. I'm thinking of the possibility of any S/N penalty caused by inserting an additional component, like an MV pot, into an otherwise solid conductor. In that case I would think the later in the path you can take a penalty, (to the extent one exists at all) the better. Or put another way, by keeping the preamp path as uncluttered as possible, the circuit design maximizes S/N as early in the chain as it can.

But having raised this distinction--construction vs. operation--there's an interesting and useful tradeoff that begins to become clear. If we accept for the sake of discussion that any pot, MV or otherwise, imparts an S/N cost to a circuit just by being there, then we could predict a small decrease in S/N beyond that point, becoming more audible as it passes through each gain stage. (As some Tweed fans might argue.) But where this sort of circuit (MV) makes its money, IMHO, is in the huge boost in S/N that becomes available by virtue of having the MV available to optimize gain structure in the preamp independently of power amp performance. (As you point out above.)

My hunch is that, properly designed, the S/N cost of an MV system in the circuit (if any) is far outweighed by the much larger benefit of optimized S/N in the preamp. Long way of saying that I too agree that MV, S/N-wise, should be a net gain, perhaps even in a little Tweed-type circuit.

Whew! So here's the rub. In the case I'm thinking of, I have a two-tube (12AX7 / EL84) homebrew circuit sitting on the workbench, in which the two preamp stages and the power amp stage are all optimized for max S/N right from the start. Great, if I want only a clean amp. But what if someone wants to drive one or more stages into saturation? Rather than optimizing S/N, an MV system would allow you to decide which stage(s) you want to saturate, and how much. In other words, the amp is indeed focussed on being a tone generator as opposed to simply being about volume. In this case, since S/N has already been maxed with the circuit running clean, every MV-type pot I insert between stages has a S/N cost, or so I suspect. If that's true, then my task becomes one of designing an MV (aka level control) system that creates the lowest possible S/N penalty while allowing independent control of saturation in each gain stage.

...All of which is why the entire subject of MV is so intriguing, and why I'm interested in knowing if there's any material theoretical substance to gripes about MV, or if it's primarily superstition, misuse, and misunderstanding. Personally, the buzz about MV is something of a mystery to me...IME the cost is small and the bennies are just huge. Especially if you happen to be soldering up a little benchtop saturation-machine.

Nice typin' at ya John, your expertise very much appreciated as always.

:BEER

--Ray

[epluribus]

And whether or not the tone is better from larger amps is subjective. I played a tele through that Vicky 5112 (at a whopping 5 watts), and have NEVER in 35 odd years of playing guitar heard more pleasing tone. Over that 35 years I have owned, played, and unfortunately lugged around, a LOT of 100 watt amps, MV and non-MV. The biggest thing I have now is a 35 watt Vibrolux Reverb, and it is too big, heavy, and loud for anything I do now. I just don't get the need for all the power, when there is a couple thousand watts in the pa?

There's a great thread on this here...

http://www.thegearpage.net/board/showthread.php?t=305146

I too am increasingly in the camp that says big and small iron sound very different beyond simple volume issues, and they aren't necessarily interchangeable, particularly when overdriven. I also believe that sometimes small-iron sound is just what you want in a big room, and big-iron sound is perfect for some songs even in very small venues. The trick is to produce the voice at volume levels that remain articulate and comfortable, and that's where sheer volume becomes a limiting issue.

Coming back around to MV, the rub there is that by dialing the volume down with MV, much of the drive character of the amp voice and dynamic changes, sometimes drastically. In that case, I'd vote for an attenuator or an isolation system of some sort as opposed to using MV. You could argue that a smaller amp may be in order, but that raises several new voice issues of its own, and may not be appropriate either.

But the tail end of MV is what happens when you want a heavily driven preamp running into a fairly clean power section--something I like to do with a DR II. Without MV, it's a case of Go Fish.

Increasingly, IMHO MV is about gain structure, not volume oddly enough. And along the same line, size and wattage aren't nearly as much about volume as they are about character, dynamics, dramatic interaction, and voice.

...And that plus five bucks'll getcha Starbucks... :)

--Ray

[John Phillips]

I don't think I was mistaking available power vs volume, at least not intentionally. I am very aware of the difference most of the time. Actually, though I am not near as eloquent, I think we were saying close to the same thing. If you play clean you need the power for the overhead, not necessarily the volume. And if you need (or like the sound of) a MV amp, or any larger amp to get your tone, that is great. But even using only 15 of your 100 available watts, you are must be playing a lot louder than me (before the PA).Probably not. The reason I need the power for the headroom isn't because I have it that loud, it's because I use a lot of effects which drastically increase the necessary bandwidth of the amp - octaver, delay, heavy fuzz (which I want to not make the amp mush out), filter etc - even phaser increase the thickness of the sound enough to do it. I also use these on full-chord rhythm playing sometimes. I doubt I'm any louder (in perceived volume in the mix) than a 5W amp turned up full for a bluesy/rock midrange distortion sound.

My Tweed Deluxe barely makes 12 watts on a good day, I only turn it about half up, and I use an attenuator with it. And I get beautiful cleans IMO (by rolling the guitar back). It doesn't sound like a big amp I'm sure, but I love it. Without the PA you wouldn't hear it well above the drums, if at all. But that is the marvel of modern PAs. And I love the lower stage volume.I like to be at the same stage volume as the drums. There really isn't any point in being quieter than that, because it means that the stage mix is mostly drums. I don't like putting my guitar back through the monitors either, it sounds odd and is much harder to use controlled feedback with.

Now the point was made that some don't have PA's at their disposal, and I suppose that happens sometimes. I haven't had to do that in quite a while. Even cheap PA's these days, have enough channels to mic an extra guitar amp. I mean, if you have a singer, you have a PA right?Yes of course, and for larger places I would mic up the amp as well rather than turning it up further - unless the stage was so big that bleed into the vocal mics etc was not a problem. But in a little bar gig, why bother? The drums are still the limiting factor, and they're not going through the PA either. It makes more sense to me (and in my experience produces a better sound in the room) to get a good acoustic mix between the instruments and only use the PA for vocals. It also usually helps avoid feedback if the only thing in the monitors are the vocals, because then they're clearer at lower volume.

I just think many, especially people who don't play cleanly, and hence don't need the overhead, try to drive the volume too high on stage with their amps, whether they have a MV at their disposal or not. And the resulting tone, IMO, is never optimal as a result.I absolutely agree with that! The worst culprits are the 'purists' with non-MV amps (and no attenuator either), who insist on cranking the thing up to where 'their tone' (ie the right amount of distortion) is, without any regard for the band mix, and then when asked to turn down, get all upset because they can't get 'their tone'. Well obviously! :) That's why you need to separate volume from gain.

I wouldn't lug around a 98lb 2x12" 100W combo if a smaller, lighter amp would do the job, either...

[pfrischmann]

I think it just depends on the circuit. I'm sure there are some folks that can design a really good master volume amp. Roccaforte comes to mind.

I have tried about 6 different master volume setups in my 100W marshall and several different circuits with particular master volumes.

I've alwaus felt the master volumes loaded down the circuit in a way I could feel. The worst one's would make the tone feel somwehat emaciated at any volume.

Unfortunately, 100W is not practical for most things....It sure sounds good though.

[Mapleneck]

Probably not. The reason I need the power for the headroom isn't because I have it that loud, it's because I use a lot of effects which drastically increase the necessary bandwidth of the amp - octaver, delay, heavy fuzz (which I want to not make the amp mush out), filter etc - even phaser increase the thickness of the sound enough to do it. I also use these on full-chord rhythm playing sometimes. I doubt I'm any louder (in perceived volume in the mix) than a 5W amp turned up full for a bluesy/rock midrange distortion sound.

I like to be at the same stage volume as the drums. There really isn't any point in being quieter than that, because it means that the stage mix is mostly drums. I don't like putting my guitar back through the monitors either, it sounds odd and is much harder to use controlled feedback with.

Yes of course, and for larger places I would mic up the amp as well rather than turning it up further - unless the stage was so big that bleed into the vocal mics etc was not a problem. But in a little bar gig, why bother? The drums are still the limiting factor, and they're not going through the PA either. It makes more sense to me (and in my experience produces a better sound in the room) to get a good acoustic mix between the instruments and only use the PA for vocals. It also usually helps avoid feedback if the only thing in the monitors are the vocals, because then they're clearer at lower volume.

I absolutely agree with that! The worst culprits are the 'purists' with non-MV amps (and no attenuator either), who insist on cranking the thing up to where 'their tone' (ie the right amount of distortion) is, without any regard for the band mix, and then when asked to turn down, get all upset because they can't get 'their tone'. Well obviously! :) That's why you need to separate volume from gain.

I wouldn't lug around a 98lb 2x12" 100W combo if a smaller, lighter amp would do the job, either...

Aside from liking a slightly different amp sound, I think you and I are about on the same page.

[Mapleneck]

I'd have to agree with the comments about stage volume & drums...why have your amp quieter onstage than the drums? Then you have to hear yourself through the monitor mix, which in anything but a large well equipped venue is usually crap anyways.

So now nobody onstage can hear what the guitar is doing other than through the monitors...which are now presumably also pumping out the keys, bass ("to keep the stage volume low") and vox too. So now you have the stage volume coming from the monitors rather than the amp, because ultimately everybody onstage needs to hear everybody else! All you're doing is replacing one amp with another (and one that's controlled by someone who isn't even onstage!).

Complicated way to solve a simple problem. We usually just try to set the stage levels around a good band mix and the PA can handle the room and the vocals.

On this I disagree though. There are lots of advantages to having your tone spread out evenly across the stage through the monitors rather than having an single point source clear across stage blasting away, and usually pointed no where near the other players ears. Not the least of which is the lower overall stage volume.

I have had friends come to jams where the PA was less than optimal, and we had to balance the instruments accordingly. And typically the only people who heard anything I played were the people (audience and musicians) closest to me. The bass player on the other side of the stage heard nothing until I was so loud the mix was totally trashed everywhere else. You just can't balance the mix from point sources.

On the other hand, the guitar barely needs to be in the monitors at all to make all the other musicians happy, and then the point source problem goes away. Yes the drums are already too loud in the stage mix, but that problem isn't solved by making everyone else too loud as well. It is an adjustment admittedly to the way guitarists have grown accustomed to being setup over the years. But once you adjust, I get all the dynamics I used to get including controlled feedback when I want it.

The volume of the drums has nothing to do with where the stage mix should be set, although it would be nice if they had a volume knob. This may account for why I fire loud drummers that have no dynamics. But I have learned to live with my sound in the monitors and have learned to appreciate the benefits. The biggest benefit being that more people actually hear me and I get more compliments that way!

[John Phillips]

I have had friends come to jams where the PA was less than optimal, and we had to balance the instruments accordingly. And typically the only people who heard anything I played were the people (audience and musicians) closest to me. The bass player on the other side of the stage heard nothing until I was so loud the mix was totally trashed everywhere else.Ah, but that's exactly one of the reasons the bigger amps are better - they're less directional at a given volume because they fill the space better. I'm not 100% sure why this is, but they do seem to...

A cranked 15W 1x12" is like a little searchlight, with 90% of its volume concentrated in a beam right in front of the amp. Bad all round, if you're not running through the PA. A high-power 2x12" combo turned down is much more audible far off-axis too, even at slightly lower volume.

The biggest benefit being that more people actually hear me and I get more compliments that way!Over the years, I've used a lot of different sizes of amp from a '59 Tweed Champ (which I was once asked to turn down, BTW!) up to a 50W head on a 4x12" and now a 100W 2x12" combo. Without exception, the most compliments on my tone and the sound of the band in general, have come when using the bigger amps.


But maybe it depends on your playing style too, or I find it hard to understand the current 'wisdom' that small amps sound better. Probably each approach is equally valid if you know how to use it properly... the difference is that big-amp users don't usually berate small-amp users for using "way too little power" or those "outdated 1950s practice amps".

;)

[Mapleneck]

Ah, but that's exactly one of the reasons the bigger amps are better - they're less directional at a given volume because they fill the space better. I'm not 100% sure why this is, but they do seem to...

A cranked 15W 1x12" is like a little searchlight, with 90% of its volume concentrated in a beam right in front of the amp. Bad all round, if you're not running through the PA. A high-power 2x12" combo turned down is much more audible far off-axis too, even at slightly lower volume.

Over the years, I've used a lot of different sizes of amp from a '59 Tweed Champ (which I was once asked to turn down, BTW!) up to a 50W head on a 4x12" and now a 100W 2x12" combo. Without exception, the most compliments on my tone and the sound of the band in general, have come when using the bigger amps.


But maybe it depends on your playing style too, or I find it hard to understand the current 'wisdom' that small amps sound better. Probably each approach is equally valid if you know how to use it properly... the difference is that big-amp users don't usually berate small-amp users for using "way too little power" or those "outdated 1950s practice amps".

;)

Well one of those "jam" instances I was refering to, I was actually using a SF Twin. But you are right, it is probably just different styles and preferences, making us demand different things from different amps. But I still say that, while a larger amp may seem to disperse better than a small one (I have noticed that too), it still can't compete with what a good pa can do, IMO.

But PLEASE don't read what I am saying as berating. And I apologize if I came off that way. My comments are more about stage volume in general, and my experiences with the benefits of lowering it. Not the types of amps people get their favorite sounds from. This to me is just an interesting discussion.

I am migrating towards smaller amps, because I get the sound I like from them. I like the sound of an amp working hard. It has been a very liberating discovery for me, to realize that I could drop down below the 'drum volume' boundary of amp output, and still use an amp that otherwise couldn't play a gig without a PA, and still get great tone out to the audience. Then, lo and behold, I even started getting better mixes as a result. But I am definately not getting "big amp" tone. So if that is your sound, you'll have to continue dragging around the bigger amp and reeling in the volume some how. But for me, the smaller amps are every bit as versatile as the big amps, thanks to pa's. I still only need one amp for any gig, and it doesn't weigh nearly as much as that old Twin did!

[John Phillips]

But PLEASE don't read what I am saying as berating. And I apologize if I came off that way.No, not at all, but many others often do.

This to me is just an interesting discussion.Yes, exactly. There is no right or wrong... unless you're destroying the sound of the band with excessive volume in the wrong place!

[HEAVENandHELL]

When one of my bands plays small bars, we use my small PA and I run sound from stage. 1st we set our stage volume so that everyone can hear each other and is comfortable with NO PA or monitors. Then I step out front and mix FOH. This process seems to work best for us so that not only do we get a good mix out front, each of us can be comfortable hearing what we need in our playing position on stage.

For the record, both guitarists have MV amps; Danny a JCM900 Dual Reverb and I a Genz Benz Black Pearl or Mesa Dual Rec.

[Structo]

Interesting reading. I understand most of what you guys are saying.
But the bottom line is, if a particular amp sounds good with a MV but at what setting does it fail to meet your tone requirements?
Like if it is turned down SPL wise but it sounds like crap, or if you have to have it quite a ways up, say 100 db to get the tone you like.

I would assume it allows the preamp section to distort which then is amplified by the power section.

How is Power Scaling different and what are the advantages to that over Master Volume controls.

[MBreinin]

Bah! I have everything from a 2 watt Lovepedal Plexi (master model!!) to a MkIII Boogie Simulclass head sitting on a 4x12 cab in my living room. The Boogie, with its monster power and very capable master can do everything for me that a small amp can do, and at whisper volumes, or cracking my slab. I always keep trying non-MV amps, mostly as a result of this board..and I always sell them or trade them. I can't use them unless they are very low in power. One of the best sounding amps I ever had was a killer Tweed Deluxe copy. It was just too loud for my use, and I wanted to play it wide open all of the time.

So, I like my tone..and I like masters. And, really, that is all that matters since I don't get paid to play guitar.

Mike

[Mapleneck]

How is Power Scaling different and what are the advantages to that over Master Volume controls.

To grossly over simplify and not bore you with technical junk, master volumes attenuate before the main amp (sometimes even before the PI), power scaling attenuates at the main amp, and attenuators attenuate after the power amp. Each has advantages and disadvantages.

[sfarnell]

Bah! I have everything from a 2 watt Lovepedal Plexi (master model!!) to a MkIII Boogie Simulclass head sitting on a 4x12 cab in my living room. The Boogie, with its monster power and very capable master can do everything for me that a small amp can do, and at whisper volumes, or cracking my slab. I always keep trying non-MV amps, mostly as a result of this board..and I always sell them or trade them. I can't use them unless they are very low in power. One of the best sounding amps I ever had was a killer Tweed Deluxe copy. It was just too loud for my use, and I wanted to play it wide open all of the time.

So, I like my tone..and I like masters. And, really, that is all that matters since I don't get paid to play guitar.

Mike

I agree for the most part. But there are some mv amps that come alive when the mv is bypassed. The TR Ruby is a perfect example. Sure, in order to play it most of the time I use the mv or risk spontaneous combustion :eek: But, when the mv is bypassed on the Ruby it comes alive and is the most toneful overdriven and responsive amp I can imagine. The change in dynamics is very noticeable, at least on my Ruby.

Mike, I see we're both selling our Rubys. Are you having second thoughts like I am?

[Mapleneck]

So, I like my tone..and I like masters. And, really, that is all that matters since I don't get paid to play guitar.

Mike

That's all that matters even if you are getting paid!

[epluribus]

The reason I need the power for the headroom isn't because I have it that loud, it's because I use a lot of effects which drastically increase the necessary bandwidth of the amp - octaver, delay, heavy fuzz (which I want to not make the amp mush out),

What a terrific insight. I opened a thread quite some time ago asking why tube purists (including me) turn around and put SS pedals in their signal path.

http://www.thegearpage.net/board/showthread.php?t=194636

Not knockin' tubefolk, cuz I'm one, :) but as a serious question. I understand the need for variety and expanding beyond the native capabilities of an amp, but from a "tubes is best" theory of building a signal path, why would you do such a thing? Or perhaps more accurately, why be so picky about keeping SS bits out of the amp istelf and then stick 'em right there on the floor in your signal path anyway? (Or--gasp--digital anything?)

Hokay, that's a whole nutha thread, but your point about bandwidth is quite useful when you're talking about using MV to control freq response in a big power section. (BTW, back in the days, I used to mistake mid-scoop for flatter freq response, and then wonder why dirt pedals made it buzzy.) I hadn't thought of this cuz I'm not a big pedal user, but now it makes sense--you need a bit better freq response from the power section to properly voice some pedals, not to mention native amp saturation and tone...without twisting the daylights out of the pedal's onboard EQ, another S/N issue. I'd not really thought of things this way. Hm...


But then on to the notion of an amp "mushing out." Now this is a strange one that I thought I was kinda in left field on. IMHO, part of the trick to really torn-up sound is...not to tear it up so much. A small MV amp like a DR II will indeed get inarticulate (particularly on note attacks, high notes, and big chords,) if you push it hard, but it'll clear right up if you back the MV off a tad and let the power section produce a shade less dirt, not to mention de-saturate that little OT a bit. Now in light of your remarks about bandwidth, and taking into account the way an OT tails off on the freq response as it saturates, this all makes tons of sense. With an MV, I can broaden the bandwidth of the amp by running the power section just slightly cleaner, allowing me to run the front end a lot dirtier, aka the amp as a whole a lot dirtier... IOW dialing in really torn up sound by not tearing it up so much. And I can still keep plenty of that power section distortion ...So that's why this works...Light dawns...Hm...

This also speaks to the question of why a small amp, or more accurately a small OT, breaks up different than a big amp. If the OT saturation and freq response is different (wider) in a heavier-built output section, the amp becomes more capable of pronouncing all the dirt you produce in the tubes. You get better note definition, better detail, and the amp can better voice thick discordants for you. No matter how you mic up a little amp with a little OT, it ain't gonna change that. Again I say, Hm...

(Which would be this thread :)...

http://www.thegearpage.net/board/showthread.php?t=305146 )



Y'know, if the above is correct, then hypothetically it would be handy to have a level control between the power tubes and the OT, to further shape OT saturation independently of power tube saturation. (Which is different than power scaling--that changes B+ which changes all kinds of things.) I would expect that if you did that, you could better control for freq response, and likewise better voice more dirt in the tubes. And shaping freq response by controlling demand on the OT would be far superior, S/N-wise, to anything you could do with a tone stack...

...And we haven't even gotten into speaker/cab distortion or freq response yet. This begins to shed additional light on why my tiny little benchtop circuit works so much differently running into a 2x12 rather than its own pint-size cab.

filter etc - even phaser increase the thickness of the sound enough to do it. I also use these on full-chord rhythm playing sometimes. I doubt I'm any louder (in perceived volume in the mix) than a 5W amp turned up full for a bluesy/rock midrange distortion sound.

I like to be at the same stage volume as the drums.

Boy, there's a terrific PA thread brewing here, something we don't do much on TGP. IMHO, doing the FOH thing teaches you small mountains about why your guitar rig works, and how it works with a band, a room, and in the heads of the audience. Plz feel free to tool off into OT-land on this, it's an important point in general, but that ultimately makes a difference in your thinking about circuit design and performance, incl the MV issue.

So jm2c...personally, I try to use PA only to fill in the little parts of the sound that you lose as you move back in the audience. I like to start building a mix by filling in the little lost parts so it sounds like you're right next to each sound source, in the best theoretical seat in the house, all at comfortable volume. (Even if you're actually in the cheap seats.) Often in a small room that means vocals and a wee bit of guitar and keyboard, maybe an overhead on the drums, but letting the low drums and bass fend for themselves.

Once I'm there, then I have the power to adjust levels, EQ, ambience, etc. and sit everybody in the mix. Finally, at that point if we just want *louder,* all we gotta do is turn it up...more or less. :)

Monitor-wise, I've found that localizing things has advantages beyond getting noise into the mics and not contaminating intentional feedback...rarely do you need to hear the whole band. Often it's just part of the drum kit or the vocalist, depending on who you're following. With localized monitors, all you have to do to change your "monitor mix" is step into the hotspot you want to hear. Besides, the apparent social interaction looks cool to the audience--it telegraphs the relationship of the instruments in a visual way. Might seem picky, but if you can do things that way, you start finding out you don't need half the monitors at all.

Hokay, that's my PA OT, I'm back to :munch.

--Ray

ps...as soon as somebody loads in with a big honkin' rig, all my big fat PA theory goes right out the window. Gr. :cool:


There really isn't any point in being quieter than that, because it means that the stage mix is mostly drums. I don't like putting my guitar back through the monitors either, it sounds odd and is much harder to use controlled feedback with.

Yes of course, and for larger places I would mic up the amp as well rather than turning it up further - unless the stage was so big that bleed into the vocal mics etc was not a problem. But in a little bar gig, why bother? The drums are still the limiting factor, and they're not going through the PA either. It makes more sense to me (and in my experience produces a better sound in the room) to get a good acoustic mix between the instruments and only use the PA for vocals. It also usually helps avoid feedback if the only thing in the monitors are the vocals, because then they're clearer at lower volume.

I absolutely agree with that! The worst culprits are the 'purists' with non-MV amps (and no attenuator either), who insist on cranking the thing up to where 'their tone' (ie the right amount of distortion) is, without any regard for the band mix, and then when asked to turn down, get all upset because they can't get 'their tone'. Well obviously! :) That's why you need to separate volume from gain.

I wouldn't lug around a 98lb 2x12" 100W combo if a smaller, lighter amp would do the job, either...

[epluribus]

How is Power Scaling different and what are the advantages to that over Master Volume controls.

Piggybackin' on what Mapleneck said, Power Scaling works by reducing the power supply to the tubes, among other things. When you reduce plate voltage in a tube, very generally speaking it makes the tube break up more, more "softly" to some ears, and it gives the amp more "feel." Tweeds tend to run low plate voltages, BF and hi-gain amps run higher voltages. If you're a soldering iron junkie, crack open an old guinea pig amp and swap out a few things to lower or raise your plate supplies (but watch your bias!)--the difference will blow ya right out of the water. Even cooler if you put a set of paralell resistors on a common switched ground--now ya got a poor-man's BF/Tweed switch.:BluesBros

But as you may gather from this thread, if you change power levels throughout the amp, a lot of other things change besides B+, complicating things.

MV generally doesn't change power levels at all, it just changes the strength of the signal going into the gain stages that come after it. IOW, B+ and all that doesn't change. So if you really want to get trick, you can wire up both an MV and your BF/Tweed switch and do all sorts of cool stuff for cheap.

--Ray

________

Everybody oughta have a guinea pig...

[Dave Orban]

Generally speaking, I prefer non-master-volume amps. But my main gigging amp is a Matchless Chieftain, and I DO take advantage of the MV, to enable me to play a wide variety of venues. I need versatility due to varying venus sizes, and even thoughout the course of a night, where I might be playing at lower volume for the first set.

Some MVs ARE better-sounding than others, and the Chieftain's MV is, to my ears at least, one of the better ones.

The Two-Rock Topaz that I gigged for a couple of years also had a great MV. The Aiken Invader that I gigged for a couple years prior, while it didn't have a MV, had a built-in attenuator that also worked great and served the same purpose.

Gigging versatility is key for me, and amps with well-conceived and executed MVs have come to the rescue. ;)

[epluribus]

Generally speaking, I prefer non-master-volume amps. But my main gigging amp is a Matchless Chieftain...

:roll Nice to see your logic works like mine Dave.

... and the Chieftain's MV is, to my ears at least, one of the better ones.

The Two-Rock Topaz... had a great MV.

Teriffic, handy stuff. Nice to have reviews so I can crib schemos and find a good way to build MVs.

--Ray

[rockon1]

A stupid question/s- whats so hard about making a "good " master volume? Why are some better than others? Or is it just the fact that some amps seem to be in need of being run harder to sound good? For instance,my Chubster seems to sound much better when its cranked up(moreso than any of my other MV amps). Is that indicative of a not so good MV? Doesnt the MV just control the amount of signal coming from the pre amp and going into the power amp? :confused: Bob

[Mapleneck]

A stupid question/s- whats so hard about making a "good " master volume? Why are some better than others? Or is it just the fact that some amps seem to be in need of being run harder to sound good? For instance,my Chubster seems to sound much better when its cranked up(moreso than any of my other MV amps). Is that indicative of a not so good MV? Doesnt the MV just control the amount of signal coming from the pre amp and going into the power amp? :confused: Bob

Not a stupid question. Again to grossly over simplify, when an amp is really working hard, every part of it is contributing to the tone, timbre, compression, distortion, feel, etc. Preamp, PI (if it exists), mains, power supply, OT saturation, speaker, and even the human ear relationships with loud sounds. They all work in concert to give the amp its character.

Every known way of attenuating an amp, removes some of these important contributors from the equation, but leaves others. If it happens that your favorite tone is your amp working hard, then you will likely not be happy with any of the various methods of attenuation, because they all take something out of the equation and the tone or feel of the amp is affected.

[epluribus]

More Than One Way To Skin A Cat Dept:

http://www.people.cornell.edu/pages/mt24/Amp/mm/mvols.html

...whats so hard about making a "good " master volume?

...oh yeah...If there's a hard way to do something, I'll find it. :)

[rockon1]

More Than One Way To Skin A Cat Dept:

http://www.people.cornell.edu/pages/mt24/Amp/mm/mvols.html



...oh yeah...If there's a hard way to do something, I'll find it. :)

Thanks! Good info. I guess I was correct on probably the most common type of MV-the type that is controlling the amount of pre amp signal going into the power amp.(pre PI) Seems to me that this would be the best method -if simple is better.

At any rate MV's have always been a necessity for me. I like pre amp distortion.How hard the power section has to work to sound good depends on the amp. I dont like saturation though. Its interesting my Chubster seems to need to be cranked up considerable more than the rest of my amps to sound its best. This thread got me thinking perhaps the MV design had something to do with it. Probably just the way it is an though and not specifically the MV. Now Im wondering what benefits the different MV designs have ,if any.Bob

[screamingdaisy]

I think you're making the mistake of confusing available power with volume - nothing personal or trying to make you feel stupid, most of the people that post here seem to not understand this either. You do not need to turn your amp up all the way. Just because you have 100W doesn't mean you need to use it all. You don't 'need' 100, or even 50, watts for most gigs - but the tone is better from the big amps, and the only way to reconcile the two if you do want to use the amp for distortion is with a good MV. (Or attenuator.) I certainly don't use my 100W amp at anything like it's full power - I'm quite sure it doesn't go over about 15W in the sort of gigs I play, exactly because I tried using a 15W/30W amp, and it was just loud enough on the 15W setting. But it broke up in ways I didn't want sometimes, and just didn't sound as full and good. On the 30W setting I couldn't get breakup when I did want it (no MV)... so I don't actually need more than 30W, even though I do want clean headroom - but still the 100W amp sounds better.



I know this is an old thread, but I had to quote this anyway. And who knows, maybe bringing this thread back to life for awhile will give others the chance to read it.

Anyway, I've been saying the same thing ever since I switched from 30w amps back to 100w. My actual volume with a 100w is more or less the same as it was with the 30w, but at 100w my tone is alot more full sounding with better clarity.

[epluribus]

Lotta really great contributions here, this seems to be TGP's definitive thread on the subject. I just linked to it from another thread (http://www.thegearpage.net/board/showthread.php?t=459399) on Amps and Cabs about the same subject. John writes a mean article, doesn't he? Cool stuff.

--Ray

[gag halfrunt]

I know this is an old thread, but I had to quote this anyway. And who knows, maybe bringing this thread back to life for awhile will give others the chance to read it.

Anyway, I've been saying the same thing ever since I switched from 30w amps back to 100w. My actual volume with a 100w is more or less the same as it was with the 30w, but at 100w my tone is alot more full sounding with better clarity.
It did! Thanks :)

[jaydub69]

Ray, bump for reference.

[epluribus]

Hi Jay.

Well, that explains it..nice to see this thread pop up...certainly piqued my curiosity. :) Always a good read whenever I re-read something by John Phillips...


...Y'know, I'm still playing with this subject. Just learned about a new MV-type circuit the other day. Gonna have to wire one up one of these days and try it out.

--Ray

[hasserl]

Installing a post PI MV in a Hot Rod Deluxe right now. The standard MV is pre PI and only works on one channel. This is a LOUD amp, the new MV will be a big help in bringing down the overall volume while maintaining most of the tone of the amp, greatly expanding the versatility.

[jzucker]

i don't know about technically but bad advice and data runs rampant through the internet forums.

[rockon1]

I don't agree. Using a big amp with flexible controls and a good MV gets you a better range of tones. I don't see how there can be any argument about that - the big MV amp will always be capable of a wider range of sounds precisely because the volume and distortion can be largely independent - it will go louder clean than a small amp, and much quieter distorted. With a non-MV amp, they're directly linked and you will not be able to get any distortion at apartment volume (not unless you're talking about a 1W-range amp, or use an attenuator).

I totally agree that amps are not just distortion generators, and I play clean most of the time. But tonally (not counting distortion) the bigger amp will very likely be capable of a wider range of sounds too, since it will probably be capable of more bass and possibly more treble, even at the same volume.

I'm not saying the quality of sound will necessarily be better - although I think it's a complete myth that MV amps always sound less good, even when played quietly - but for flexibility, you absolutely need to separate volume from tone and distortion.

I don't like my big MV amp beause I have 'monster truck issues' :) - in fact, for years I would never even use a 2x12" amp because I thought it was unnecessarily big, and certainly not a stack (much too 'rock' ;))... I prefered to hit hard with a small amp - I like it because it sounds better than the smaller amps I've used (at any volume) and means I don't need to own or carry more than one amp for any size of venue. By 'better', I mean bigger, deeper, more powerful and dynamic. If you like smooth, more compressed tones where your touch affects the tone rather than the volume the opposite may be true.


Technically, one reason that a lot of MV amps can sound 'fizzy' or 'buzzy' at lower volumes is because the power stage is capable of cleanly and equally reproducing all the frequencies generated by the preamp, and distortion contains dispropotionately more highs (and lows to some extent) than clean. In a non-MV amp, by the time the power stage distorts, it will also be heavily loading the power supply and probably the OT - and even the speakers - which produces compression and a narrowing of the bandwidth into the midrange, so it helps smooth out the peaks and chop off the high 'fizz' and low 'buzz' frequencies.

So in fact, it's not that MVs 'degrade' the sound - it's actually power stage distortion and compression that degrades the sound, but in a way that sounds pleasing :D.

Not all MVs sound the same though, depending on exactly where they are in the circuit.

Damn I miss this guy here! He was really helpful and informative.Dead on old post! Bob

[epluribus]

i don't know about technically but bad advice and data runs rampant through the internet forums.

Say it ain't so Jack! :)

[JimmyR]

Yup I used to agree with almost everything JP said. I like using bigger amps - from 35-50W for exactly the same reasons John Phillips quotes. While I LOVE the tone of my 5E3 cranked it is still too loud for some gigs used that way and sounds like poo played dirty with my 6120 or with a delay.

So for a rockabilly gig I might use a Bassman or Lop-po Tweed Twin (homebuilt clones, anyway) and stick a good OD and delay in front. That way not only can I get great clean AND dirty sounds but get better low-end definition and twang from my Gretsch. For replicating a small amp miced and then put through a slapback delay ala Sun Studios I find using a bigger amp and a dirt pedal just works better and is far more gig-friendly.

As far as MV amps I don't think they are always inferior. I have two 50W Marshall clones - one is a pretty close copy of a '68 1987 plexi, the other uses identical parts but is based more on a JMP 2204 circuit. The MV is one of the much maligned pre-phase inverter but I love it. The plexi style sure sounds amazing when cranked but I have never played a gig where the volume needed for optimum tone would be acceptable. Plus the bass strings can get a little woolly. With the MV circuit I get a different OD tone - not better or worse necessarily, but definitely different - and I do need to run the amp at a decent volume to get it sounding good. But it's a great, very usable tone the way I have it set up, and I actually prefer the low end response. It sounds great at a wider range of volumes and is easy to get sounding good at gig levels.

I only have two amps with master volumes but for what I use them for they are wonderful.

[samtheman]

Naylor amps master volume, its unique desing, sounds very great even with very low volumes, but I think whole amp circuit is unique ??

/sam