Trouble with Emanating Fist Black Acid: sounds Muted, pots acting weird

[suryabeep]

Hi folks,
I just built an Emanating Fist Black Acid from the layout at https://tagboardeffects.blogspot.com/2017/05/emanating-fist-electronics-black-acid.html . Some weird stuff is happening: The fuzz knob acts as a Tone knob as well as a fuzz knob, it sounds like the treble is rolled off everywhere except max. The drive knob is acting as a volume knob as well. The whole thing sounds fine when everything is maxed out, but sounds muted when anything isn't maxed out.
I was using 2x 2N5088s but then changed one out for a BC109 (Q2), the problem persisted in both. For discussion, I'll call the transistor on the right side of the board Q2 and the one on the left Q1. Q2 (EBC): 1.37, 1.97, 5.95. Q1(EBC): 1.95, 0.62, 0.
I tested continuity of ground, jacks into circuit in/out, and 9v supply and all are fine. Double checked resistor and cap values and those look fine too (I only piggy-backed two resistors to give me 530R instead of 560R, but I figured it wouldn't make much difference). Pot values are correct, I checked using my DMM (I finally know how to use it thanks to a prior thread). The jacks aren't shorting against the enclosure either. I'm pretty stumped as to what could be the problem?

[suryabeep]

bump*

[duck_arse]

is it possible your trimpot is backwards? see on the face, it has a little diagram, of a resistor side to side, and a wiper to the "top". if your wiper is not on the right side of the track cuts, it might welll cause trouble.

[suryabeep]

is it possible your trimpot is backwards? see on the face, it has a little diagram, of a resistor side to side, and a wiper to the "top". if your wiper is not on the right side of the track cuts, it might welll cause trouble.

I think the trimpot is fine, the resistor symbol is to the right side, and the pins align correctly with the layout.

[blackieNYC]

I love DAM products, but that name! We need a Most Over The Top Commercial Pedal Name Contest. Over in the Lounge or something. 
Good grief.

[duck_arse]

but on this layout, the little resistor symbol on the trimpot would be on the left hand side. reversed in the same place, the wiper would be in a cut. can we see the underside of your board?

[edit :] and now that's twice I've forgotten to make comment on the name.

[Gus]

Just ran a sim the voltages look good for the 20k trim pot set to 1/2 way (10k). You want trims to be set about 1/2 way in a good design.

A 500k volume will have an affect on the tone
http://www.diystompboxes.com/smfforum/index.php?topic=96381.msg838899#msg838899

The drive will add resistance to the base dropping the gain everywhere but the ends of travel. At the ends of the travel the 1uf or the .0047uf are direct to the base.
The 220pf cuts highs you can make that lower for more highs

The fuzz knob issue might be a connection issue at the fuzz wiper to 22uf cap or neg side of the 22uf cap to ground. Check the wiring in that section and check or change the 22uf cap

[suryabeep]

EBK, the trimpot is working correctly, the resistance between the tracks changes with turning the trimmer. I think I found the problem - the little link underneath the trimpot was making contact with one of the pins, causing the resistance to be 0 between all three pins. I pulled it out, fixed it, put it back in, and now the pedal works much better. What I'm noticing is that the Fuzz knob acts as a Fuzz/Treble knob, and the Drive knob acts as a drive/Bass knob.
Thank you all for the help!

[blackieNYC]

The drive pot appears to be "panning" between two input caps - one rolls off a little bass, the other is allowing most low frequencies in to the circuit.  A nice feature.

[bamslam69]

I breadboarded one of these up last night.
What's annoying is a lack of schematic, which I redrew from the layout.
I think I only had one exact resistor, the rest were a collection of series & parallels to get the right figure. Even the pots were a collection of old pots from cannibalised guitars, or 2 pots in series for the trimpot! After only a couple of hiccups (missing jumpers), I got it working.
This thing sounds pretty damn cool. A nice heavy bassy fuzz. i might have a bit of a fiddle around with some simple mods tonight, but I'm looking forward to building this one.
It just needs a name...