Red llama question- not quite right yet

[jimbob]

I got it working- sort of but it doesnt seem sounds right yet. The sound seems to break up after a strum of the guitar. Any idea what may cause this? Anyone else w the same issue.

Of the changes I made were- 220 uf instead of the 330 uf and a 1n914 instead of the 1n4004, and 120pf instead of the 100pf.

Im using this layout

http://gaussmarkov.net/layouts/layouts.html#redllama

[Mark Hammer]

Not a single one of those changes should make any audible difference to 98% of all ears.

[brad]

Make sure the chip is the unbuffered version (should have UBE or thereabouts on it).

[A.S.P.]

either:
wrong chip (non-UBE);
wrong wiring/PCB-traces, extremely wrong component-values, or pinout-mistake;
faulty input-cap;
faulty output-cap;
non-conductive fuzz-pot;

btw: the 1M resistor at the output is completely unneccessary,
as long as the vol-pot is in working order!

[Peter Snowberg]

Breakup typically comes from an incorrectly set bias somewhere. The Llama uses a pair of inverters, and each one sets it's own bias voltage so you shouldn't get and gating from impropper bias adjustment.

I think Brad may have the answer. Does your chip say 4049B or 4049UB?

[markm]

Yes,
That UB is very important as I have read that using the buffered version causes problems in that circuit.
Don't know about gating but, it will cause occillation big time!

[jimbob]

part # 595- cd4049ube mouser

I can now get a decent sound but at the end of the strum of a chord theres a gating breaking up type sound. Damned thing! Its always these simple projects I have problems with.

[A.S.P.]

is that just the part # you ordered,
or is that what actually is printed on the chip?

[jimbob]

cd4049ube is what is actually on the chip

[A.S.P.]

then swap the output-cap for a different one...
(electrolytic is OK for testing - watch the polarisation!)