XC Phase - noob question

[Jimbaaaab]

Hi

Noob question/check. I just finished up the CX phase. I get bypass sound, but with pedal engaged I don't get any sound at all. I have sockets my transistors (including the matched quad), and made sure to apply pressure to them in case there was a missed contact somewhere, but still no sound. I'm guessing this is something idiotic, like I've soldered the jacks incorrectly or something, and thought I'd check with you guys before continuing to troubleshoot. Front and back pics attached. I also took advice from other threads posted here and changed IC3 to a TL022CP. Grateful for any guidance. Cheers.

 

[SlowAudio]

Looks like your transistors are backwards? They should be flat side towards the camera.

 

[Robert]

Looks like your transistors are backwards? They should be flat side towards the camera.

This looks like one of the first batch of PCBs with reversed silkscreen on the JFETs.

Are those 2N5952's? If so, they're correct.

 

[Jimbaaaab]

Yep, 2N5952s. They read between 294 and 295. I turned them all around, and Q5 (2N4125). Still no sound when foot switch is engaged.

 

[Robert]

Sorry, just noticed, your DC jack is wired backwards.

Jacks - PedalPCB Wiki

wiki.pedalpcb.com

 

[Jimbaaaab]

Thank you. That did the trick! I now have phase There's a ton of 'whooshing', but I'm guessing I need to adjust the trim pot and find a good balance. Does that sound right? Actually, I just flipped Q5 so that the flat side is facing the C500K pot and the whooshing has disappeared. I'm guessing I have that in the wrong way around. All the transistors now have the flat side facing the C500K.

 

[Robert]

The 2N4125 should be oriented according to the silkscreen.

Only the 2N5952's need to be reversed.

And for anyone just tuning in, this only applies to that specific PCB revision. If your PCB has the "Rev 2" marking in the bottom right-hand corner or the dotted lines surrounding the JFETs you should install the transistors as shown on the silkscreen.

 

[Jimbaaaab]

Thanks so much for all your help @Robert. I got this boxed up this morning and it sounds great. I had a 90s Block script MXR Phase 90 and sold it for $50 some years ago to get a Small Stone Phaser. I've regretted it ever since (not the Small Stone ), but there's something about the Phase 90 that's unbeatable. This pedal is going straight on my board and I don't think it'll be going anywhere for some time. Some pics attached. Thank you!

 

[jimilee]

Thanks so much for all your help @Robert. I got this boxed up this morning and it sounds great. I had a 90s Block script MXR Phase 90 and sold it for $50 some years ago to get a Small Stone Phaser. I've regretted it ever since (not the Small Stone ), but there's something about the Phase 90 that's unbeatable. This pedal is going straight on my board and I don't think it'll be going anywhere for some time. Some pics attached. Thank you!

I find jfet phasers a little more chimey than OTAs. They are my favorite as well.

 

[Jimbaaaab]

One more thing before I leave you all in peace. I noticed that when I put the XC after some fuzz (a Hizumitas, to be precise), there's quite a noticeable drop in volume when it gets to the amp. Are there any specific component I can replace in the XC to rectify this? Many thanks.