Adding presence, or something else

[daz]

true, and i can't remember which tap it's on now. But i tried all of them with various resistor values. And i found that they didn't seem to make enough difference to change the resistor value as much as i'd have thought. Between 4 and 16 there would be i'm sure, but between the 2 i mostly use, 8 and 16, there wasn't that big a difference. I just mentioned the sweet spot because someone mentioned a 100k and a 100k pot in series, and on any tap in my amp that would be pretty harsh unless the pot was set to zero resistance regardless of which tap i used.

[daz]

I agree. I was in the local music store a few weeks ago and they wanted me to try out a new Mesa MkV. Forget it! For me it's just a nightmare. Knobs and switches everywhere. I told them I justed wanted to turn one knob.

Yep, those things are a nightmare. But what happens is this. You find different things that both seem to sound good in different ways. So you tend to want to make it switchable. then before you know it you've found more things like that and you end up with a boogie ! What i found is that once i found what i feel is the magical tone in this amp, or the perfect balance, (as close as i'll get or matters anyways) all of a sudden every one of those multiple good but different things is no longer a multiple choice....now theres only one obvious winner, and therefore the amp no longer needs all that. Thats how it worked out for me anyways. I stopped tweaking this amp i've tweaked forever because once i found this amazing balance, anything i change kills this tone. so there is no longer a need for switches and all that. To me mesas sound horrible. Or more accurately, FEEL horrible. I think thier whole philosophy is to add so many switchable things that thier amp can be tweaked to anyone's ideal tone. But it doesn't work that way. Seems to be a darn good marketing ploy tho !

[überfuzz]

Off topic, slightly: I like the process of finding sweet spots. However, when I found it all the knobs and pots changes from possibilities to an evident risk of messing up my tone. Well you know how it feels when the amp isn't ringing like it should and you're performing on stage.

This build has one 3 pot equelizer to each channel. One reverb pot and one presence, or whatever you like to can it, effects both channels. Normaly I use my twin reverb and it has 3 pot eq, reverb and tremolo. That's how I roll!

[Wilder Amplification]

I personally like to make the NFB loop frequency selective in favor of the lower frequencies (i.e. a maxed out "Resonance" control). I set mine up on the 16 ohm tap with a 100K resistor, then place a 10nf (.01uF) cap in series with the NFB resistor. Gives a nice a phat low end boost for frequencies 160Hz and below if you're not overdriving the PA. You can get the same result with a 47K and a 22nF (.022uF) on the 4 ohm tap.

[booj]

I think the 250k pot is audio taper. The 68k reduces the effect of shorting the pot. It sounds very similar to the negative feedback type circuit used in Marshalls. I copped the basic idea from a Matchless