Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: bruno on April 15, 2010, 03:58:05 pm

Title: single tone control options...
Post by: bruno on April 15, 2010, 03:58:05 pm
I really enjoy single tone control amps, as I'm not big on fiddling with knobs... I love tweed deluxes for example, however I find the early single tone control from fender to be a little overly bright, and quite interactive with the tone control and overall gain of the amp!

I'd like you guys to tell me more options for single tone controls, I've been looking all over the net and found quite a few nices ones, and tubenit also gave me a nice idea of using a baxandall/james type with a dual pot. I've also noticed a lot of cool unknown amps from the 50s and 60s have "funky" tone controls which are sometimes forgotten as really good implementations. I've also been looking at local NFB options to control overall tone or power amp cut controls.

But I thought I'd ask for even more ideas, here if possible. I'm looking for something for a tone stack that allows my signal to be relatively clean and clear with good gain transition, and that is not too bright sounding like the early fender tweeds can be.

For example my ac15 twin with it's single cut control is rather jazzy sounding in the normal position, until it breaks up.

New ideas are welcome.

Thanks
Title: Re: single tone control options...
Post by: Merlin on April 16, 2010, 05:15:06 am
I love one-knob controls too! The options are fairly limited though. Useful ones include:

Tweed Princeton: http://amps.zugster.net/images/articles/tonestacks/tweed-scheme.gif

Big Muff PI: http://www.muzique.com/lab/tone3.htm

(Also I will take the opportunity to pimp my own variation on the Big muff control:   http://i81.photobucket.com/albums/j207/merlinblencowe/BoaneRayStack.jpg?t=1271412650 and Bridged Differentiator: http://i81.photobucket.com/albums/j207/merlinblencowe/ParametricMidScoop.jpg?t=1271412680

Bridged-T: http://www.schematicheaven.com/gibsonamps/ga30rvt.pdf (See the middle control, right before the 2nd triode)

Garnet semi-active: http://www.schematicheaven.com/gibsonamps/ga30rvt.pdf (See the treble control on the 2nd triode)

There's probably a couple more, but the ones above are definitely the more versatile options.
Title: Re: single tone control options...
Post by: darryl on April 16, 2010, 07:26:42 am
My favorite one-knob tone control is the type used in the normal channel of the Watkins Dominator (http://www.schematicheaven.com/bargainbin/watkins_dominator.pdf). It also appeared in a Dominator clone - the Marshall 18-watt.

This tone control can be a little dark, but a fixed or switchable bright cap across the volume control will lift the highs.
Title: Re: single tone control options...
Post by: Boots Deville on April 16, 2010, 08:01:36 am
If memory serves, I think the tone control from the 18W LiteIIB addresses the darkness issue of the original 18W.  I wanna say it's from the 18W tremolo channel, but don't quote me on that!  :smiley:

The tone control in Doug's 18W Stout differs from the 18W Lite - anyone know where that get's it's inspiration from?
Title: Re: single tone control options...
Post by: RicharD on April 16, 2010, 08:14:35 am
Here is my current flavorite 1 knob tone control.
Title: Re: single tone control options...
Post by: Fresh_Start on April 16, 2010, 09:26:44 am
Here's a pretty cool discussion of different tone controls:
http://amps.zugster.net/articles/tone-stacks

This discussion may also be helpful; however, my firewall labels the site "supsicious" so go at your own risk:
http://www.angelfire.com/electronic/funwithtubes/Amp-Tone.html

Cheers,

Chip
Title: Re: single tone control options...
Post by: stingray_65 on April 16, 2010, 10:52:33 am
I've always wanted to try this tone stack from a Gretsch 6162.

Title: Re: single tone control options...
Post by: Fresh_Start on April 16, 2010, 10:59:23 am
I've always wanted to try this tone stack from a Gretsch 6162.

That's a beautiful hexagon, but how the heck does it work?  Is the 500K pot on the left side a volume pot (and a highly interactive one at that) or just part of the tone circuit?

Mostly rhetorical quesitons... I'll try to study it later.

Chip
Title: Re: single tone control options...
Post by: echuta13 on April 16, 2010, 11:00:09 am
The "tilt" control looks really interesting.  I think Merlin mentioned the Gretsch 6162 in his book.  I've been wanting to try this out in a build.  
Title: Re: single tone control options...
Post by: Merlin on April 16, 2010, 11:49:43 am
That's a beautiful hexagon, but how the heck does it work? 
Nothing fancy, it is the same as the BigMuff Pi, except that it uses 2nd order filters instead. (e.g, instead of RC it uses RCRC)
Title: Re: single tone control options...
Post by: tubenit on April 17, 2010, 06:08:50 am
You can take most two knob tone controls and make them a ONE knob tone control with dual ganged pot.
Such as I suggested with the James tone stack. However, you could do the same thing with a Princeton Reverb
tone stack or a Dano Centurian tone stack for example.  You could even do it with a Marshall tone stack with
a fixed resistor for the mid pot etc..............

I found it relatively easy to solder a terminal strip on the back of a pot. In fact, the Dano I owned came that way.

That opens up ALOT more choices. You can also add a resistor from wiper to ground to change the taper.

With respect, Tubenit
Title: Re: single tone control options...
Post by: birt on April 17, 2010, 12:26:36 pm
I've always wanted to try this tone stack from a Gretsch 6162.



that looks like a twin-T. used in several wah's
Title: Re: single tone control options...
Post by: plexi50 on April 18, 2010, 07:41:31 pm
Pic from an earlier thread
Title: Re: single tone control options...
Post by: PRR on April 18, 2010, 10:14:12 pm
>> this tone stack from a Gretsch 6162.

> same as the BigMuff Pi, except that it uses 2nd order


Yes; though awful "soft 2nd order". Still that gives quite sharp slopes:
Title: Re: single tone control options...
Post by: tubeswell on April 19, 2010, 02:42:33 pm
Pic from an earlier thread

Yup the 5F2A tone stack is good enough for rock'n'roll