madbeanpedals::forum

Projects => Tech Help - Projects Page => Topic started by: jprizz on March 12, 2013, 08:34:38 PM

Title: Sea Urchin - volume loss
Post by: jprizz on March 12, 2013, 08:34:38 PM
I've completed my Sea Urchin and it works except that I get a serious volume loss when I engage the effect. So much so that it is unusable this way. Everything works like it should except for the volume loss. My PT2399's were locking up so I have tied pins 3 & 4 together as suggested elsewhere. The voltages all look good on both chips and the regulator. Are there any components I should check or swap out that could be causing this? Or could this be a bad batch of PT2399 (from Tayda). Thanks for any guidance.
-Josh
Title: Re: Re: Sea Urchin - volume loss
Post by: jimilee on March 12, 2013, 09:18:36 PM
Typically it's a resistor value that's off, like 100k instead of 10k for example. That's the first place to check. Ugghh I know what a pain.
Title: Re: Sea Urchin - volume loss
Post by: mysticaxe on March 13, 2013, 12:22:43 AM
If it is also the dry signal, look at the resistors around the opamp.  The one i built is definitely unity volume.
Title: Re: Sea Urchin - volume loss
Post by: jprizz on March 13, 2013, 03:14:12 AM
You were right Jimi, I had a 39k in R3 instead of 360k. I usually measure the resistors before hand but obviously I missed this one. Hopefully swapping out will correct it. Thanks again guys!
Title: Re: Re: Sea Urchin - volume loss
Post by: jimilee on March 13, 2013, 03:15:27 AM
Do keep us updated
Title: Re: Sea Urchin - volume loss
Post by: jprizz on March 14, 2013, 03:50:02 AM
That fixed it! Sounds awesome now. I'll post up when I get some pics.
-Josh