has anyone noticed this?

[iknowjohnny]

Maybe it's just my amp, i dunno. But thru all the experimentation i've done i seem to notice that the higher the value i use for a slope resistor, the amp sounds better if i lower the value of the treble cap. For example, if i have a 47k slope, a 500pf treble cap sounds best. When i up it to 68k a 250pf sounds best. I came to figure it must be because when you lower the amount of signal that gets past the slope to the bass and mids, you're left with a larger balance of treble frequencies from hi mids on up. Makes the tone a bit too thin and harsh. And therefore a 250pf lets less high end thru. It allows the higher frequencies but rolls off the treble at a higher point leaving you with less overall treble, and at a higher range which is softer than the high mids that have been subdued with the 250pf. No?

[JD0x0]

The lower the slope the more overall gain, bass and mids you get. so raising the treble cap will add upper mids and treble to compensate. and Visa Versa. The treble cap kind of pushes where the treble will start rolling off into the mid scoop on most preamps. An obserdly high value on the treble cap can actually take the mid scoop away completely or even move the "scoop" into bass frequencies.

Ive been experimenting with a mid boost that switches in a 20n cap for the treble cap. It only works correctly with a very low mid cap which im currently using is 4n (as opposed to 22n on marshalls or 10n on Dstyle)

The treble control then becomes the boost control. Treble on "10" will give a tone stack bypass kind of feel with a slight drop off in the lowest bass frequencies. Treble on "5" has less gain but creates a flat EQ with a "hump" in the low mids up to about 1khz. With treble on "0" you get even less gain but a really cool wah sound as the bass and treble cut out leaving the mids

[iknowjohnny]

Interesting. I've fooled with the tone stack a lot, but i never got that deep into it like that. I noticed a badcat i think it was which had a 50 pf treble and a 100k slope which got me to thinking about it. I didn't take it that far, but a 68k/250pf worked nice to balance the tone a little better and clean up a bit of low flab. I have my preamp up to the point of the tonestack at a point where it sounds phenomenal and i cannot change it at all or the great tone goes away. I obliviously found some sort of perfect balance there. So now i'm playing with the tonestack to take that great tone and balance the frequencies to perfection. at this point it's nice, but i think i can do better. But it sounds like you pretty much found the same thing i did as far as the relationship between the slope and treble cap.

[JD0x0]

I like 120K slope and 330pf treble for cleans
and 40K slope with 200pf for OD

Of course the values can vary especially since the amps i build (ODS clones) run the clean channel into the OD. Hence the higher slope and lower treble cap on OD. Also with the higher slopes i will usually go with lower value bass caps to compensate, i really like the low mids to come through on my amps as i find the frequencies in the low mids most pleasant to my ears without the bass getting out of control

[PCollen]

The lower the slope the more overall gain, bass and mids you get. so raising the treble cap will add upper mids and treble to compensate. (snip)...

EXACTLY what Marshall did when going from the 56K/250p to 33K/500p in the tone stack for lead amps.

[iknowjohnny]

The lower the slope the more overall gain, bass and mids you get. so raising the treble cap will add upper mids and treble to compensate. (snip)...

EXACTLY what Marshall did when going from the 56K/250p to 33K/500p in the tone stack for lead amps.

That 33k/470pf combo is just so muddy and dark tho. And i may be wrong, but it seems to me that they had to make up for that by adding a lot of brighteners elsewhere like the 470k/470pf filters in the JCM's. W/o those the 33k/470pf stack would be a mud fest. thats why i don't use it. I LIKE that combo and the low mids it gives, but i find in making the amp bright enough to overcome the muddiness that brings it just ends up too bright while also having a muddy bottom. Somehow voicing it the other way around, IE: brighter tone stack, darker gain stages, seems to make for the best balance w/o issues with brightness and muddiness. Thats what i find anyways.

[JD0x0]

none of my old marshalls seemed muddy. It may have been my settup though. At one point i was using a 74' JMP with the treble on "0" mids "10" and bass "3" no mud for me, even cranked up where things can get mushy.