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muff77
09-24-2009, 05:42 AM
Hi

I have an old 70s Hiwatt 50w with a 2X12" cab loaded with Fane's.

I want the tone as clean as possible but I feel that it's a bit too agressive. It doesn't distort but when I use pedals with the amp they sound a bit too boosted. I've compared the amp with other Hiwatts from the era but and they're much cleaner or milder. Difficult to describe exactly what I mean but can the amp be tuned for a cleaner tone by adjusting the bias, using different tubes or is there another method?

The cab is for some reason loaded with two 8ohm speakers in 4ohm in total. Can this have an effect on the tone?

Thanks!

darkbluemurder
09-24-2009, 06:24 AM
Hi,

I am not sure which model it is but have you tried the normal and/or low input? And when you compared it to other Hiwatts did you use the same speaker cabinet?

I have read somewhere that wiring the speakers in series instead of parallel would give less highs but I have not tried this myself. This mod is also only recommendable if your amp can be set to 16 Ohms (wiring to 8 Ohm speakers in series gives 16 Ohms).

If it's only a one channel amp with one input then I would check whether there is a bright cap on the volume control, and if so, take it out.

Cheers Stephan

muff77
09-24-2009, 08:00 AM
But can adjusting teh bias make the amp less agressive?

plexistack
09-24-2009, 08:18 AM
Yeah you can back off on the bias, try a clean set of power tubes, use a 12at7 or 12au7 preamp tube in V1.

A resistor change can often reduce gain as well, find a _good_ tech.

ROKY
09-24-2009, 08:36 AM
Hi

I have an old 70s Hiwatt 50w with a 2X12" cab loaded with Fane's.

I want the tone as clean as possible but I feel that it's a bit too agressive. It doesn't distort but when I use pedals with the amp they sound a bit too boosted. I've compared the amp with other Hiwatts from the era but and they're much cleaner or milder. Difficult to describe exactly what I mean but can the amp be tuned for a cleaner tone by adjusting the bias, using different tubes or is there another method?

The cab is for some reason loaded with two 8ohm speakers in 4ohm in total. Can this have an effect on the tone?

Thanks!

I'm not 100% sure I understand your post .

If your dirt pedals sound too 'boosted' you might want to adjust
the gain and levels carefully so they aren't WAY louder than the
clean tone you've set on the amp.

But, again .. I'm not exactly sure what your meaning is about the
amp itself being too ' aggressive '.

I have a Hiwatt 50 myself and it doesn't give me ANY problems
with pedals; quite the contrary .

FFTT
09-24-2009, 08:43 AM
How about your guitar and pickups and your attack?

These amps clean up so nice when you lay back on your attack even
with HB's, but you'll get cleaner results easier with single coils or P-90's.

You might have a tech check the bias and cool it down within specs
and look into pre amp tubes with less gain.

michael.e
09-24-2009, 08:52 AM
Old Hiwatts do not have a bias control. Something may have drifted from spec, I would have a tech run through it and make sure it was up to snuff.
Then, if it is a 100 watter, sell it to me!

muff77
09-24-2009, 03:18 PM
I'm not 100% sure I understand your post .

If your dirt pedals sound too 'boosted' you might want to adjust
the gain and levels carefully so they aren't WAY louder than the
clean tone you've set on the amp.

But, again .. I'm not exactly sure what your meaning is about the
amp itself being too ' aggressive '.

I have a Hiwatt 50 myself and it doesn't give me ANY problems
with pedals; quite the contrary .

Well, I have no problem getting a clean tone from the amp but the clean character - if you know what I mean - sounds a bit too punchy and "in your face". I like the clean tone to have punch and a clear top but in my opinion there's a fine balance between a perfectly balanced clean tone and one that's a hair too nasty.

Doesn't really matter if I adjust the gain or volume on the pedals, because the amp doesn't seem to react that well with high gain pedals all together. I've tried my pedal board on other Hiwatts and it works nicely.

I guess it's a matter of taste but as I feel the difference between mine and the other Hiwatts that I've tried is that evident, I want to see if there's a way to tame it a bit.

muff77
09-24-2009, 03:20 PM
How about your guitar and pickups and your attack?

These amps clean up so nice when you lay back on your attack even
with HB's, but you'll get cleaner results easier with single coils or P-90's.

You might have a tech check the bias and cool it down within specs
and look into pre amp tubes with less gain.

My main axe is a US 57 Strat with Custom Shop 69 pickups. Shouldn't be too much power in them to make an impact.

I'll have a tech look at it.

Passenger84
09-24-2009, 03:33 PM
I've found that sometimes old tubes can make things sound harsh, as opposed to leaving a 'give' in the sound. Also, pickup height, and over-watted speakers. I'm really not sure if any of that applies, just some experiences I've had. :) I'd try a tube change, and maybe even a speaker change. And if that doesn't do it, as folks have been mentioning, maybe some lower powered preamp tubes. I've had good luck softening amps with 5751 tubes.

muff77
09-24-2009, 04:55 PM
I've found that sometimes old tubes can make things sound harsh, as opposed to leaving a 'give' in the sound. Also, pickup height, and over-watted speakers. I'm really not sure if any of that applies, just some experiences I've had. :) I'd try a tube change, and maybe even a speaker change. And if that doesn't do it, as folks have been mentioning, maybe some lower powered preamp tubes. I've had good luck softening amps with 5751 tubes.

Ok, thanks for the tips! I think the "problem" is the amp. The speaker cab, pedal board and guitar/pickups, sound right on/with other identical amps.

CitizenCain
09-24-2009, 05:05 PM
Clean and punchy describes HIWATT. Maybe you need a different amp?

keto
09-24-2009, 05:13 PM
Clean and punchy describes HIWATT. Maybe you need a different amp?

Totally THIS. I have an '81 DR504. Clean + any kind of loud = VERY IN YOUR FACE, it's just the nature of the beast. You can up your pre to get it to compress a bit more, but then it won't be *as* clean. Or, try running a compressor up front to take a bit of the peak off. I personally don't think there's anything wrong with your amp, it describes exactly what mine does and it has fresh tubes and is fresh from a tech trip.

muff77
09-25-2009, 05:54 AM
Totally THIS. I have an '81 DR504. Clean + any kind of loud = VERY IN YOUR FACE, it's just the nature of the beast. You can up your pre to get it to compress a bit more, but then it won't be *as* clean. Or, try running a compressor up front to take a bit of the peak off. I personally don't think there's anything wrong with your amp, it describes exactly what mine does and it has fresh tubes and is fresh from a tech trip.

Well, perhaps I'm being overly picky but we're talking nuances here anyway and I was wondering if there's a way to fine tune it.

I've A/B tested my head with two other Hiwatt 50ws from the same era and they're slightly warmer and not as aggressive.

Steeltoe
09-25-2009, 06:58 AM
If you have the 4 input model, the inputs on the top
are the lower gain inputs. Jumpering the channels
gives you the best tones, as you can blend the two,
and set master to taste.

solitaire
09-25-2009, 08:54 AM
"Aggressive" could be interpreted as a snappy response (solution: compression somewhere in the signal chain, perhaps a compressor or compressive pre-amp valves), nasty trebles (solution: turn down treble or replace valves with darker sounding ones) or high gain, large headroom valves (solution: use lower gain valves). A general solution would be less efficient, lighter magnet speakers.

Then it could have something to do with a change of values of filter components.

ROKY
09-25-2009, 09:38 AM
Well, I have no problem getting a clean tone from the amp but the clean character - if you know what I mean - sounds a bit too punchy and "in your face". I like the clean tone to have punch and a clear top but in my opinion there's a fine balance between a perfectly balanced clean tone and one that's a hair too nasty.

Doesn't really matter if I adjust the gain or volume on the pedals, because the amp doesn't seem to react that well with high gain pedals all together. I've tried my pedal board on other Hiwatts and it works nicely.

I guess it's a matter of taste but as I feel the difference between mine and the other Hiwatts that I've tried is that evident, I want to see if there's a way to tame it a bit.

I understand what you're saying, now.

I had a 100 watter and the guy who sold it to me had other 100 watters,
and said that the one I bought was not his favorite, despite tube
changes, etc... SO, there can be differences, certainly.

You've compared yours to others and find that [the one you have]
is not playing well with your setup, for some reason.

muff77
09-29-2009, 02:26 PM
Exactly :)

I've been using JJ Electronic EL34 tubes for some time but I have no idea what's in the preamp stage. Are JJs known to be of the warmer, milder kind of tubes? Or do you have anything to recommend?

jerrydyer
09-29-2009, 02:43 PM
try a 5751 as the first preamp tube

solitaire
09-29-2009, 03:24 PM
Exactly :)

I've been using JJ Electronic EL34 tubes for some time but I have no idea what's in the preamp stage. Are JJs known to be of the warmer, milder kind of tubes? Or do you have anything to recommend?From what I know most JJs are slightly edgy and raw sounding. I'm more inclined to the chinese EL34s, which are rather balanced, fat and swirly. Very ruggied, more so the newer HT-type.

Mike9
09-29-2009, 03:41 PM
Being a 70's era amp it probably needs some maintenance - things like a cap job, resistor value check, little things like that. All that drift affects the tone so if you just bring it back to spec you might be shocked at the way it sounds.

muff77
09-29-2009, 05:17 PM
Being a 70's era amp it probably needs some maintenance - things like a cap job, resistor value check, little things like that. All that drift affects the tone so if you just bring it back to spec you might be shocked at the way it sounds.

I just got it back from a very skilled tech and he's replaced some caps and brought everything as close to original specs as possible. The amp sounds much more pristine and tighter.... and louder! But it's still a bit nasty. It's probably my taste but I though I'd try some milder tubes before I decide on keeping it or getting a new amp that perhaps better suits my needs.