SOLVED ADHD doesn't sound like an OCD (weaker gain less body/fatness)

[ChrsGuit]

Just finished an ADHD build for a friend. This is the newest version of the PCB. My buddy loaned me his v 1.7 OCD to compare once finished... The Pedal sounds great, but is extremely lacking in volume, fatness, and gain... I went back and checked the transistors and silly stuff. All solder joints have been reflowed. Swapped the IC, etc. Don't get me wrong, pedal sounds great but it is very weak in the volume and gain department and I feel it sounds lacking to the genuine article... Something has to either be wrong on my end or I need to change some values to try and get it up to snuff. Any ideas what I should be checking first?

 

[ChrsGuit]

As long as they are opposite of each other, the silkscreen orientation doesn’t matter so much.

On this particular board they are silkscreened in the same orientation, but not in the circuit itself

 

[ChrsGuit]

As long as they are opposite of each other, the silkscreen orientation doesn’t matter so much.

My guess is a dead gain pot... I'm getting proper resistance sweep on leg 1 to center but nothing on leg 3 to center...

 

[Barry]

My guess is a dead gain pot... I'm getting proper resistance sweep on leg 1 to center but nothing on leg 3 to center...

Are you moving the sweep when measuring? Better yet where is the sweep set when measuring?

 

[Barry]

Forgive the slopy Flux mess. I had it cleaned up fairly well til I started reflowing joints I'm seeing no shorts or bridges

That solder shouldn't be dull looking or balling up like that, I think you got some cold joints. What are you soldering with?

 

[ChrsGuit]

That solder shouldn't be dull looking or balling up like that, I think you got some cold joints. What are you soldering with?

Are you moving the sweep when measuring? Better yet where is the sweep set when measuring?

Yes, I'm slowly rotating the pot. 500k pot, which should increase to 500k on one outside leg and opposite for the other leg. I'm soldering with a Hakko fx888D and using 60/40. I think that "dull" look could just be my lighting as they all look good and shiny in person... The "globbing" is from re-flowing. for whatever reason when I reflow, it pulls a small bit back up as I pull the iron up, leaving a goofy "blob".
I've checked all my pads on the front end and have good flow-through to each component

 

[ChrsGuit]

That solder shouldn't be dull looking or balling up like that, I think you got some cold joints. What are you soldering with?

I'm testing all my resistors currently... my 1m R1 is giving me nothing... I MIGHT have just found it

 

[Laundryroom David]

This may just be the lighting but it looks like a bridge

 

[Harry Klippton]

... The "globbing" is from re-flowing. for whatever reason when I reflow, it pulls a small bit back up as I pull the iron up, leaving a goofy "blob".

This happens with poor quality solder, not enough heat, and/or a dirty tip

 

[ChrsGuit]

This happens with poor quality solder, not enough heat, and/or a dirty tip

I tried using Kester, but I'm deathly allergic to pine oil. I built three pedals with it and I was DYING the next morning... I eventually put two and two together... I've got three fans running and it's still not enough... I didn't like how the Kester flowed either... it would always try to run and I bridged COUNTLESS connections because it would "string" along as I pulled the iron away

 

[ChrsGuit]

View attachment 55082This may just be the lighting but it looks like a bridge

I checked it out... it was a little piece of fuzz from a q-tip

 

[ChrsGuit]

Ended up with a bad trace or something in the last build. No audio probe signal pre- C7 (working from output of circuit backwards...). Tested all components, reflowed the joints multiple times, NOTHING.
Scrapped it and populated another board Michael so graciously sent me (what a stand-up dude!)... Pedal was much improved but still underwhelming in the gain department... Swapped several different diodes in (I socketed the diodes) and settled on some 4148's... They sounded much more crisp and the gain wasnt so "papery". Still didn't have that "umpf" the genuine pedal did... I took apart my buddies 1.7 and noticed it has a A1m drive pot...
I removed the A500k gain pot and swapped in an A1M...

NOW we are talking... A cleaner, more crisp, equally powerful pedal with WAY less noise, hum, and buzz...

 

[jesuscrisp]

That makes zero sense but ok, glad it works.

 

[ChrsGuit]

That makes zero sense but ok, glad it works.

How do you mean?