freestompboxes.org

bugg wrote:

marshmellow wrote:C10 should be at the junction of R8/R9, not at the opamp output.

I won't argue that it should be, but I'm fairly certain that it wasn't.

@marshmellow As long as C10 is in the Vref net, there's no big difference. Check the pics in page 1 of this thread.

Looks like this is the origin of that elusive tone section

Duckman wrote:

bugg wrote:

marshmellow wrote:C10 should be at the junction of R8/R9, not at the opamp output.

I won't argue that it should be, but I'm fairly certain that it wasn't.

@marshmellow As long as C10 is in the Vref net, there's no big difference. Check the pics in page 1 of this thread.

Placing a capacitor of that size on an opamp output is just wrong, regardless of what the "designer" of the pedal did.

http://www.analog.com/en/analog-dialogu ... er-25.html

bugg wrote:Traced from original, all SMD caps removed and measured.

CharlesEQ.jpg

Full schematic (and PCBs) available here:
http://www.pedalpcb.com/product/angrycharles/

Hi,

thank you very much for your work. I noticed that R18 is 10k in the pedal guts shots at the beginning of this thread, so I think you should correct it in the schematic.

Cheers,
Giulio

Hi friends
I've made a clone of Angry charlie V3, its sounds amazing and have a nice and warm distortion but i think it has less treble, what is your recommendations for increasing about 30-40% treble to tone of this pedal.
https://www.pedalpcb.com/docs/AngryCharles.pdf

What about c19 (2n2 cap) in treble tone stack?
Do you think Decreasing it is beneficial or not?

R19 (6.8k) and C17 (22n) at the output form a low-pass filter with a corner (-3 dB) at 1 kHz. Reduce the value of C17 to raise the corner frequency which will give you more treble. 10n = 2.3 kHz, 6.8n = 3.4 kHz, 4.7n = 5 kHz, etc.

mauman wrote: ↑19 May 2023, 19:57 R19 (6.8k) and C17 (22n) at the output form a low-pass filter with a corner (-3 dB) at 1 kHz. Reduce the value of C17 to raise the corner frequency which will give you more treble. 10n = 2.3 kHz, 6.8n = 3.4 kHz, 4.7n = 5 kHz, etc.

Is decreasing C7 (100p) is beneficial for increasing treble?

What about C19 (2n2) in tone stack treble section?

This three-band Baxandall tone stack (copied from Douglas Self's Small Signal Audio Design book) will give you 12 dB of boost and cut in each band, which is quite a lot. The treble control works from 1k Hz up, and the mids are centered around 700 or 800 Hz. If you can't get enough treble by adjusting the mids and treble pots, I'd modify or even remove that output lowpass filter (R19/C17), which is killing your treble.