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Let's Get Technical => Troubleshooting Problems => Topic started by: Moff40 on August 28, 2022, 03:24:31 PM

Title: Solid State Clean Gets Nasty
Post by: Moff40 on August 28, 2022, 03:24:31 PM
I was playing around with SS clean on my MP-1s, and was reminded of something that’s been happening since the beginning:  SS Clean works OK with OD1 up as high as 5.5, but any higher, and a strong strum will throw it into a fuzzy kind of distortion.  It’s not rhythmic, just on a strong strum, depending on the OD1 setting, will stay for a few seconds or longer, and then fade back out till the next “trigger”.  Any ideas?  Flaky diode?
Title: Re: Solid State Clean Gets Nasty
Post by: rnolan on August 29, 2022, 06:30:15 AM
May be OD1 trim pot setting?  worth a look.
Title: Re: Solid State Clean Gets Nasty
Post by: MarshallJMP on August 29, 2022, 11:39:20 AM
What is the setting of OD2?
Title: Re: Solid State Clean Gets Nasty
Post by: Moff40 on August 29, 2022, 12:19:08 PM
OD1 trimpot is between 50 and 75%, but it can be backed right off and it still happens.

OD2 on the front panel is quite low, 1.0 or 2.0, although I’ve changed it up and down from there.  Strangely, this only happens on SS settings; tube settings are fine.  That said, as I write this, I realize even my tube voicings don’t use an OD1 setting above 5 (I find there’s plenty of gain available in the 3-4.8 range).  I’ll experiment to see if it also happens on tube settings.
Title: Re: Solid State Clean Gets Nasty
Post by: Moff40 on August 29, 2022, 02:15:25 PM
OK.  I had a bit of time before work, so dug in a little further.  It DOES happen on Tube Clean, but can’t really tell in tube dist (by the time you get to 5.0, there’s tons of “good” distortion already happening).  It’s OK with OD1 settings under 5.0, but at 5.5, a strong stum will cause a jump in the amount of distortion for a few seconds, then it will drop back to normal if I let the chord ring out.  At higher ID1 settings, the “fuzz” just lasts longer before eventually returning to normal.
Title: Re: Solid State Clean Gets Nasty
Post by: Moff40 on August 29, 2022, 09:34:51 PM
By the way, this is on the unit that I just de-modded, not the one that was raised from the dead (I have nicknamed that one “Lazarus” :) ).  It had been doing it before that, but since I don’t generally use SS, I didn’t think too much of it.