Comments on: Amp Tone Controls: Tone & Gain Sucking Leeches?

By: Mike Johnson

Mike Johnson — Thu, 28 Jan 2021 11:26:12 +0000

The first guitar tube amp I built was a single-ended, single 6V6 output, single twin-triode preamp build. I does not have a TMB tone stack and I opted to shape tone by employing switchable cathode bypass caps on both preamp gain stages and the output tube. The preamp(V1 & V2) cathode bypass caps are as follows (on-off-on DPDT switch):on=1uF/off= unbypassed/on=22uF.

The 6V6 output tube also has an on-off-on DPDT switch. on=10uF/off=unbypassed/on=2200uf. The 2200uF tightens bass.

I also installed switchable (on/off), adjustable global negative feedback to further shape tone and clarity. These mods are very useful throughout all volumes.

Even on amps I’ve purchased or built over the years if they have a TMB stack I generally set it and don’t touch it much. I definitely prefer the raw sound of a amp without a tone stack.

By: Harold Brooks

Harold Brooks — Sat, 09 Mar 2019 17:53:04 +0000

One thing I have found by playing with tone controls and EQs over the years (applies more to a distorted rock tone, but starts when there is any type of compression of the tone), is that when you add or remove a frequency, the others fill that space in the signal. So if I were to drop lower mids in my crunch tone, magically, a bit more base and treble fill in that signal void. So the concept of tone controls are actually very dynamic when you are working with a compressed (distorted or otherwise) signal. Again, this phenomenon starts right at the point of the tube soft clipping, that is sometimes not perceived as harmonic distortion.

I have come to the point that I recognize my best tones by swapping guitars (that all have different pickups), swapping pickups, or using an external EQ. The thing with using a solid state EQ in front of a tube amp is quite different that having an amp with tone controls. First off, the EQ is generally a ‘clean’ device that can BOTH boost and cut signal bands, and with quite more a degree of precision if you use a 10 band or a parametric EQ.

I have a couple of amps with NO tone controls that were made back in the 1940’s by Valco, and they are indeed SUPERB ! Touch sensitive, and respond phenomenally to any input tonal changes from the guitar pickups, or an EQ. They ‘Morph’ into many different sounding amps with input tonal changes, far more than any amp with built in tone controls, and I’ve owned over my tenure perhaps 50 amps (currently a dozen), and played another 50 in studios and at sessions with friends, so I have a pretty good basis for comparison.

For me ? No more built in passive tone controls. I run a “Raw” bypass switch on my amps with built in tone controls, and tailor the input frequencies by changing guitars and using an EQ pedal up front.

That’s the most flexible and far and away the best sounding approach I’ve ever found.

Hats off to Don Mackrill !!! You have some deep insight, run with it !!!

By: Brad Taylor

Brad Taylor — Thu, 27 Sep 2018 17:42:03 +0000

Hello:
I’m finding your post rather late but am fascinatingly confused! When I turn my tone control(s) clockwise I hear some band of frequency increasing, so not all frequencies must be attenuated..correct? Also I do perceive a small loss of gain when tone is severely minimized. I tried this with my Fender Blues Junior and telecaster so far, and I must say with that particular combination I did get excellent tone and results. I would like to hear more at your convenience. Thanks!

By: Stewart Ward

Stewart Ward — Fri, 18 May 2012 09:26:38 +0000

My 1981 Sessionette:75 amp design (55,000 manufactured) feature an EQ Bypass switch on the drive channel. It was a very popular feature. The amp ceased production in 1988, but we still see demand for them. Used by Dave Gilmour, Eric Clapton, Jan Ackermann, Roy Buchanan (via Mark Dronge), Dave Stewart and loads more… the amp is unashamedly 100% solid state and is a classic here in Europe! More infor here: http://www.award-session.com/sessionette.html You’ll find some of my ‘designer standpoint’ articles on the Manuals page too, if you’re interested!

I am a complete SS convert since 1981! And known (despised) for it! LOL!!!

Good luck.

By: Bill Wilkat

Bill Wilkat — Wed, 04 Apr 2012 14:40:09 +0000

I enjoyed your article. Tone is so elusive for many, and not well understood with respect to pots on guitars and amps. I find more clients now forgo the tone control altogether on their guitars, and favour pickup selection / combination, and a single pot for volume. This tells me that my ears are not unique, and makes sense, given that so many guitar players never really use their guitar’s tone controls.

Best regards from Canada!

By: Steve

Steve — Mon, 03 Jan 2011 10:11:04 +0000

Hi Don,
Great article! Thoroughly enjoyed.

I found you by searching on “Gain sucks tone”. Here’s why…

I’m fed up of hearing chainsaw guitars, and I’m convinced that too much gain kills the character of the guitar making them all sound similar. I was trying to find some evidence that would help me convince a fellow guitarist to back his pre-amp gain off a little to let his guitar come through. I’d be really interested on your thoughts on this.

Very best regards from France