RED LLAMA, CRAIG ANDERTON TUBE SOUND FUZZ CAP ACROSS OP-AMP #1

[phazon]

So, I had purchased Craig Anderton's book "Electronic Projects for Musicians".  Tube Sound Fuzz project sounded cool.  After tooling around onthe internet, found out that the Red Llama is esentially the same pedal with some capacitor values changed.  I built the Red Llama.  Works, but does not sound as good as I had expected.  It seems to have a kind of drug down sound, sort of cheesy and muddy.  I have since noticed something about the schematic.  Both the Tube Sound Fuzz and the Red Llama schematics show a cap across the in-out of the first op-amp in the chain.  In the case of the red llama, this would be across term 5 and 4.  But...when you look at the PDB diagrams available, the cap is in series with the 100k resistor coming off the drive pot....  hmmmmm...  is there a reason for this?  Are the PCB diagram wrong?  Is this why mine does not sound quite fabulous?

schematic
https://lemonlimefx.wordpress.com/guitar-pedals/red-llama-clone-rev-1-0/

PCB's
http://effectslayouts.blogspot.com/2014/11/way-huge-red-llama.html

http://effectslayouts.blogspot.com/2014/11/way-huge-red-llama.html

[anotherjim]

It's different, but not necessarily wrong.
It could be a mistake.
It could be an attempt to make it a bit brighter at low gain, but I don't think would do much.

I think this is one of those effects you either like or don't - and it can be a totally different experience between ordinary single coil or high output pickups.

[Les Turnbull]

When I built my UBEscreamer with the same CD4049 chip the resistor between pin 3 and 6 was given 3 options , 100k single coils , 220k regular buckers , 330k/470k hot buckers , My red Llama sounds marshall like with my RG560 single  coils but a bit muddy with my Yammy SG , So perhaps a 3 way switch with the 3 different resistors may make the Llama match the plank better .

[Mark Hammer]

The cap will roff off highs at a lower frequency as the gain in stage 1 is increased.....assuming the PCB corresponds to the schematic.

Personally, I like to use larger-value interstage caps (C1, C4) and lower-value feedback resistance (R2, R3, gain pot) to extract a bit more bass and less gain out of the invertor....but that's me.  Anderton's original schematic, as you are aware, uses an even larger feedback resistance in stage 1 for "fuzz".  Jeorge Tripps opted for using the circuit in more of an overdrive mode, and ditching the fuzz mode.  Myself, I like to keep the gain in the invertors modest and use an op-ampgain stage ahead of the circuit to hit it harder.

[blackieNYC]

Mark has tweaked this nicely.  You can connect the output of his IC1A pin 1 to C8, skipping the frequency boost stage:
http://gaussmarkov.net/layouts/49r/49r-schem.png