What other kind of amps have power scaling....

Discussion in 'Amps and Cabs' started by HaloMaster, Jun 21, 2006.


  1. HaloMaster

    HaloMaster Silver Supporting Member

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    I have been looking at a coulpe of amps that have power scaling. (maven peal, mojave) Are these amps a valid option for playing at home and at gigs because you can change the power output. Is there any other amps that do this? How do these amps sound? Why don't more companies use this? anybody own this kind of amp, what is the upsides/downsides to these type of amps?
     
  2. KOTR

    KOTR Supporting Member

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  3. tonefreak

    tonefreak Member

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  4. drbob1

    drbob1 Silver Supporting Member

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    Dave from Maven Peal's only hear once in a while, so I'll put in his response till he gets here: Mojave, London Power, and Reeves all use a straight pot to reduce the B+ voltage on the power tubes called "Power Scaling". His patented Sag circuit uses a sophisticated, feedback regulated power supply to control all aspects of the power output of the amp, giving more exact control over output power and sustain.

    All of these amps work well, and would be ideal for having the same basic tone in variable sized venues. None of them will practically pull the power down to TV volumes without it becoming kind of buzzy...
     
  5. myles111

    myles111 Member

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    I prefer amps that are not compromises and run at their full rated output. If you want this sort of functionality then buy an attenuator such as an airbrake or hotplate.

    I do not like this extra "stuff" built into my amp. These power reducers can be complex and/or generate a lot of heat.
     
  6. r9player

    r9player Silver Supporting Member

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    Stephenson has power scaling
    Koch master volume not bad at all either and it has a Direct output for headphones.

    Personally I have used a hotplate (and the hotplate build in on a Univalve) and that just wasn't my thing, felt that the sound coming out wasn't quite representing what I heard without and at times I had to attenuate very high so it really changed the tone.
    I liked the Maven Peal the best (and so that is what I have) true can't go down quite to TV volume because you wont have any power to drive the speaker. But Great representative sound at various wattage settings.
    I had a Stephenson before and though the power scaling worked well, I couldn't bond with the tone it had.
    I also have a Pritchard (in the emporium) which has excellent wattage control and a low wattage output plug for the speaker, but again just couldn't quite get my desired sounds at desired volumes from it. If you can live with loud party room volume at home and what ever club volume you might possibly need, this is a great amp.
     
  7. LaXu

    LaXu Member

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    Attenuators and power scaling can't be compared. The difference is very obvious. The more you attenuate the more compressed the tone gets and the more high end you lose. This doesn't happen with Power Scaling at all. Until you get to very low volumes (speakers no longer pushed at all and the effect of volume on hearing is reduced) a Power Scaled amp sounds pretty much the same as it would on full blast. Had a Stephenson with power scaling but ended up selling it mainly because the feel of the amp wasn't well suited for what I was playing (hard rock) - too loose. Perfect for blues though.

    I tried several volume reduction methods side by side and together. Power Scaling was the most transparent, but I was surprised by the following setup:

    Tube amp -> dummy load with line-out (many attenuators have this option) -> separate (solid-state) poweramp -> cab.

    This I believe is pretty much how the Ultimate Attenuator works, just that the load and poweramp are stuffed inside a single box. Anyway, compared to power scaling there was a little compression and high end loss, but nothing that would ever bother me. You get very precise control over volume too and could use post-amp effects (amp -> dummy load w/line-out -> fx -> poweramp -> cab), although I didn't try this since I own no fx aside from an overdrive pedal. I might end up using this kind of setup with the Diezel Einstein combo when I get it, depending on how good the master volume on the Diezel is.

    Speaking of master volumes, those can work well too. At the Helsinki Guitar Show a few months back I tried Finnish made Monster amps and was really impressed by the bypassable master volume. To me the amps sounded pretty much the same at all volumes (excluding the afore-mentioned effect of volume on hearing and speakers being pushed). I don't know how the master volume on those is done, but it worked very nicely.
     
  8. fullerplast

    fullerplast Senior Member

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    Power scaling is less of a compromise than an attenuator IMHO. You can run at full power if you want with no impact at all. There is nothing in the signal path. It is not equivalent to an attenuator tonally or physically. It is not especially complex nor does it generate more heat, unlike an attenuator which pushes the amp to extreme levels and stresses both tubes and output transformers and does generate more heat. Power scaling actually results in a cooler running amp.

    Power scaling has the distinct advantage of both not being in the signal path and also extending tube life considerably if the scaling is used. It also minimizes risks to the OT while the attenuator maximizes risk. Tonally, while every amp and attenuator is different, I much prefer the tone of power scaling to any attenuator I have heard. It is also continuously variable, while many attenuators are stepped. You can dial in 3 percent reduction in voltage if you want and just get a bit of "brown" effect.

    Regarding the original question, JMJ Amps utilizes power scaling and is licensed by Kevin O'Connor (London Power). Excellent amps and excellent implementation of power scaling.
     
  9. sovtekking

    sovtekking Supporting Member

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    I apologize for being completely off-topic here, but my rockerverb50 (orange) has a master volume that doesnt get buzzy at all at lower volumes so maybe that'll be an option for ya...just a thought cause it works so well for me
     
  10. HaloMaster

    HaloMaster Silver Supporting Member

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    I have been checking out the mojave amps and they seem really nice. does the power scaling effect the tone of the mojaves at all? I basically play in church so it would be great to have the power scaling option for bigger or smaller rooms.
     
  11. GuitarBrent

    GuitarBrent Member

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    I couldn't agree with Fullerplast's comments more. Great, intelligent, informed response. Halo, my Mojave Sidewinder sounds great. The power scaling only starts to sound a bit buzzy at it's extreme lower settings, but even then it still sounds 10x better than any attenuator on the market, and I've tried a number of them. See my response to your Scorpion question. I would suggest you look at the lower wattage Coyote model, so you won't have to use as much of the power scaling in lower volume situations. That 50 watt Scorpion will be LOUD.
     
  12. alanbass1

    alanbass1 Member

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    What about a Carr Mercury, which I have played and sounds really good at 'home' volumes.
     
  13. Nomadgtr

    Nomadgtr Member

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    What GuitarBrent says about the Mojave is right on. I have a Peacemaker and use the Power Dampening at home all the time. Not sure what kind of stuff you do in church but I'm pretty sure that unless the congregation digs classic rock plexi-like tones you don't want to go with the Scorpion or Peacemaker. A Coyote would be a good choice though. The Power Dampening beats the heck out of attenuating by a long shot. I only notice a slight smoothing out of the tone when I apply full dampening. Don't really notice any tonal change on other settings though. On full it takes the 100 watt Peacemaker down to 6 watts. Pretty cool.
     
  14. KOTR

    KOTR Supporting Member

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    I have not had any problems with my Reevse getting buzzy at very low power levels. Some that have experienced this may not be using the amp in a manner that achieves the best results. As the Power Scale is turned down, the amount of signal required to drive the power section is reduced, too. The manual reads......

    "When scale is set to maximum the power amp produces full wattage, any other setting will produce less than full wattage. Scale set to minimum is in the standby mode.

    The volume control determines the amount of saturation and compression that the preamp and poweramp produce. As the amp is scaled down the volume control should also be turned down to keep the amp's natural full volume tone. A good rule of thumb is: adjust the volume and scale no further than 90 degrees from each controls setting. In other words, if the scale is set 1/2 way then set the volume no more than 3/4 of the way. Of course you can adjust to taste, if a compressed saturated tone is desired, then turn down the scale control and turn up the volume. If cleaner, higher headroom tone is desired then turn the scale all the way up and back down the volume control to taste."

    In practice, I have been able to scale the power to max and set the volume to get the amount of power tube overdrive I want and then reduce the scale to the loudness I desire and only reduce the volume control a very little to re-acquire the orignal tone I had selected at full power. I was skeptical when I read the london power info before making my purchase but I must say that it works great. WAY better than any attenuator I have tried or heard.
     
  15. r9player

    r9player Silver Supporting Member

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    I don't think of it as 'buzzy' myself, but the speaker is just hardly being moved and thus the sound is 'off' from what it would sound like at 1 Watt or higher actually the Lovepedal 1/2 Watt does a good job even driving, sound louder then 1/2 to me.
     
  16. dhines

    dhines Member

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    In response to an earlier post, power scaling is not a compromise, especially compared to other options like attenuators, dummy speaker loads, half power switches, etc.... All of the other options really change the tone and response of the amp.

    Power scaling, when done right, allows you to maintain the same tonal response through the entire power range. With our amp, Reignamps.com, and other great amps like Mojave and Maven Peal, you should be able to strum a chord or single note and then turn the power control through the entire range without hearing any change in EQ.

    Regardling fizziness at low power - that's really more a problem with not having enough power to drive the speaker. Our typical cabs have 2 50watt Eminence speakers. At 3 watts you just aren't going to have enough juice to drive them. So for lower volume playing we recommend a low wattage Celestion Blue, a Jensen, or something along those lines.

    The power scaling will help improve your playing for sure - you will find yourself "playing the amp" more often, even in small practice settings. There are some great models out there and they tend to be very reliable and your tubes will last 5 times as long. Why? As an example, our amp is 20 watts max. The majority of our customers almost never get above 15 watts. I played a 5000 seat arena at 11 watts and was large and in charge. :D

    And Reeves has a good model out too.
     
  17. Macaroni

    Macaroni Member

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    I recently received my new Kingsley Deluxe 32C (review coming soon), and I had Simon integrate the London Power Scaling kit into it. It works really well, and is much better than an attenuator, for all the reasons stated in the above posts.
     

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