ISOSCELES Super Low Output on Fortin Mode

Finished my build last night of the ISOSCELES. Pedal is working and the TC mode sounds great, but when I switch to Fortin mode (the toggle on the left to go between preamp and boost called SW1) there is a massive drop in volume (regardless of the 33 or Grind toggle mode). In TC mode all is fine, bass/treble respond and it sounds great, solid output and hits the amp nicely.

I read in the reviews about people saying they had super low output and the only specific thing I found in forum was one builder who swapped R4 to a 19K (mine is the stock 15k).

I did not sub out any parts other than the BC549C for a BC550C because you can't get BC550C anymore. I even tried swapping the BC549C for a 2N5089 (installed backwards) and it made no difference.

I have a home brew audio probe and a DMM. I suppose step one is to DMM check all of the values of all caps and resistors? All of the electro caps I used are 35V or higher rated and are Nichicon or JB. Mostly WIMA brand box film, all good stuff in the pedal. Here are pics. I accidentally hit the top of that C4 cap and put a slight indent on it, same for the very big C12 but I don't think they hurt the box films, functionally.

Could really use some help here... It's odd that I read about this pedal having issues in the reviews and my build has those same issues. I do not have a spare TL071 or a spare TC1044SCPA to swap with, unfortunately.
 

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YEEEEEEEEEEES!!!!!!!!! I GOT IT!!!!!!!!!!!!!!!!!!

STORY TIME. On the initial build, I f'd up on SW1. When I mounted it and soldered and then flipped the board over I noticed that it was crooked and cocked to the inside facing the LEVEL knob at about a 20 degree angle and I never would have been able to mount into my enclosure properly so I knew I had to desolder it and reposition it.

Well, before doing a desolder, I thought perhaps I could bend it/reposition it back to a straight orientation and in doing that, I basically broke it and had to completely remove the first SW1 from the board and desolder it and clean up the holes to make room for a new SW1. Thankfully I had a spare ON/ON SPST so I soldered a new one in and on the backside of the board it looked great with nice solder flow so I went on to testing my new pedal. I fired it up and as stated, the TC preamp was great but the Boost/Fortin had like... really low output. The SW1 thing was in the back of my mind while this was happening...

So I was probing around with my audio probe and not having much luck at all so I did a full on eagle eye over the whole goddamn pedal. I noticed when looking down "in between" the bottom of SW1 where the pins are and where they connect to the PCB, it did not look like a good enough contact and I could see the pins of the SW1 and the top of the PCB and the traces and it looked a little suspect there. The backside looked great but def. a bit red flaggy at the angle I was looking from. So I fire up the iron and totally reflowed that SW1.

VOILA!!!!! BOOOOOOOOOOOOOOYAAAAAAAAAAAAAAAH! WORKING!!!!!!!!!!!!!!!!!! ALLLLLLLLLLLLLLRIIIIIIIIIIIIIGHTTTTTTTTTTTT!!!!!!!!!!!!!!


The Boost mode now has correct volume and the toggle to go between 33 and Grind works. When it is UP there is just a hair more treble to it. GREAT PEDAL!!!!!!!!!

SO. Lesson learned. Make sure SWITCHES go in straight from the get go. My least favorite things to solder are mini toggles and box film caps.

THANK YOU ALL!
 
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