Arche Boost, Thickening?

[EZS]

I really like this boost as is. However I know it can be fine tuned, but would ask for some Zen Guru guidance before blindly swapping caps.
In a higher gain, already bright Marshall style amp, for that over the edge shred tone, when engaged, boost at min, lows halfway up, the overall signal is just thinned out considerably.
Should I increase C4? Not sure how the EQ is filtered in this circuit.
All suggestions please. Thanks in advance.

 

[HamishR]

I've used a 12nF cap in parallel with R10 to take some of the edge off and I find that helps. If you're only ever using to boost a very distorted signal you could go higher - 22nF can sound good as it reduces some of the fizz of the distortion. 12nF seems to sound quite neutral to me.

It seems to me that the boost is generally a little brighter than unity. If you brighten and boost you end up with even more high end which can make things sound a bit fizzy as that extra high end gets distorted. Slightly darkening the boost can make the overall sound a bit thicker.

You could also probably make C3 a bit bigger if you prefer. Others here may have better suggestions. I have used the cap across R10 and it works for me.

 

[EZS]

Both good suggestions. Before dumping highs to ground, I was wondering what that network C2, R2-3-4-does? And if C4 is just small. Maybe a .022u?
Im not savy enough yet to use spice emulations.

 

[BuddytheReow]

Both good suggestions. Before dumping highs to ground, I was wondering what that network C2, R2-3-4-does? And if C4 is just small. Maybe a .022u?
Im not savy enough yet to use spice emulations.

Leave C2 R3/4 alone. DOn't they look awfully similar to R100, R101, and C101?............ R2 helps bias the opamp. Leave that alone as well.

Do you want more bass or less treble?

 

[EZS]

Leave C2 R3/4 alone. DOn't they look awfully similar to R100, R101, and C101?............ R2 helps bias the opamp. Leave that alone as well.

Do you want more bass or less treble?

More lows to come through. When this is activated on an already brightish preamp, it really thins out.

 

[BuddytheReow]

Then you'll need to look at the LOW control. C4, R6, and LOW form a high pass filter. Fully CCW, it will let anything over 700hz. Fully CW, it will let EVERYTHING through. Keep in mind that its a A-taper pot, so you'll get the maximum sweep effect in the later half of clockwise rotation.

I think you just need to dial up the LOW control a bit more...

 

[EZS]

Im liking it at about 1/2 up maybe touch more before bass gets farty. Ill try upping the C3 pf cap. Little at a time. Thanks for input.