Dirtbaby distortion

[somnif]

If you can peek at the board when you're testing it, do you notice the Green LED hugging the 2399 lighting up? Strike a really hard, high volume chord and see if it glows. If not you may have it in backwards (or a really low output instrument I suppose, but its worth a look anyway)

[taeagan]

Yes, I checked and the led glows.  It got me thinking about the post in the other thread talking about the forward voltage of the led.  All of my green diffused checked out in the 1.8v area.  I don't have any leds with a voltage drop greater than 2v as the other poster had suggested (at least not according to my meter).

[Boba7]

Yes, I checked and the led glows.  It got me thinking about the post in the other thread talking about the forward voltage of the led.  All of my green diffused checked out in the 1.8v area.  I don't have any leds with a voltage drop greater than 2v as the other poster had suggested (at least not according to my meter).

Oh yeah I remember it made a big difference in the last Dirtbaby I built.

[taeagan]

Ok. So I socketed c12, C10, and r4 as per the other thread. No difference at either 9v or 18v.

Is there another LED or diode combination that I can try? I'm not sure that I completely understand how the "green led trick" works. If it's limiting the signal to the forward voltage of the led, should I try something with a lower forward voltage? My green LEDs all measure 1.8v on the meter. Should I try a red one? Or am I washed up here and I want something greater than 1.8v?

I did find an older thread where midwayfair stated:

"Keep in mind that ALL PT2399 delays have harmonic distortion problems. That sounds like a soft, static-y, trashy distortion on the repeats."

http://www.madbeanpedals.com/forum/index.php?topic=17796.0

Maybe that's what I'm hearing? Maybe I'm trying to run down something that can't be fixed?