November 19, 2009 at 4:20 pm #79345jwny72Member
I’m trying to equalize the output volumes between my Stereo Polychorus’s engaged and disengaged status. There are 8 internal trimpots. Does anyone know what they all do?November 19, 2009 at 4:22 pm #103922
Didn’t I already answer this question for you?November 19, 2009 at 7:09 pm #103931jwny72Member
Almost, but not entirely. Adjustments to TP3 did alter the delay/chorus effect intensity (clockwise rotation reduced the amount of feedback and the volume of the repeats). Adjustments to TP2 produced no result whatsoever that I could detect. Before moving on to adjust other trimpots at random, I was hoping to get input about what they’re all supposed to do.November 19, 2009 at 7:16 pm #103932
Don’t touch the others as they’re for delay IC bias and other things.November 20, 2009 at 6:35 pm #103989
The trimpot alignment of a pedal of this complexity should not be undertaken by anyone that is not an experienced technician. You need an oscilloscope, an audio signal generator, a diagram showing the locations of the trimpots and their functions,and the proper procedure. Without all these things, you will probably just worsen the misalignment.
Howard Davis, EE – Designer of the Stereo Polychorus
Guitar pedal design engineering, repairs, and custom mods:
http://howard.davis2.home.att.net/November 23, 2009 at 2:39 pm #104109
So, is it possible to adjust the output volume from any of the trim pots or not? Simple answer would be nice.November 23, 2009 at 2:50 pm #104111Quote:So, is it possible to adjust the output volume from any of the trim pots or not? Simple answer would be nice.
Short answer: noNovember 23, 2009 at 3:24 pm #104112
It could be just me, but I think the volume boost of Polychorus is somewhat annoying. It’s noticeable. Is there something you can do about it?November 23, 2009 at 5:53 pm #104118Quote:So, is it possible to adjust the output volume from any of the trim pots or not? Simple answer would be nice.
Yes, but there is more than one trimpot that affects output level.November 23, 2009 at 6:48 pm #104121nightravenMember
basically – get howard to fix it :pNovember 24, 2009 at 8:30 am #104147
Is there a reason why trim pots aren’t explained in the manual already? They usually are if a pedal has them.November 24, 2009 at 7:39 pm #104184Quote:Is there a reason why trim pots aren’t explained in the manual already? They usually are if a pedal has them.
Trimpots are for adjustment by a qualified service tech only. To encourage anyone else to tamper with them is to encourage people misaligning or even damaging their pedals. As far as I know, there are no service manuals issued for EH pedals.November 24, 2009 at 11:36 pm #104197electro-melxModeratorQuote:Is there a reason why trim pots aren’t explained in the manual already? They usually are if a pedal has them.
Is there a reason that the pots are inside the pedal rather than stuck on the front with knobs on?
….answer, yes!November 4, 2010 at 6:33 pm #112390gibsonrdMember
Hey everyone! So I have a reissue polychorus I picked up. I am having the same issues with mine as listed above with the loud volume increase when engaged. I tried ajusting the trim 2 and 3 with no results and now the pedal is not functioning properly. The chorus is coming out of the flange setting, and the flange is coming from the filter matrix setting. Can someone take a pic of their trimpots and post it for me? Or can someone post a better explanation of what each trimpot is used for? Any help would be greatly appreciated and thanks.
- You must be logged in to reply to this topic.