Ibanez CP-9 level knob problem HELP

[zacharybroyles]

Yeah so i just got a vintage cp-9 pedal and the level knob doesnt do much, Its not that big of a deal but it does bug me. All the connections to the pot and board look good so maybe the pots just bad. Heres a picture and any help would be great. http://www.guitarpedalmods.com/images/100_0617.jpg

[zacharybroyles]

anyone?

[zacharybroyles]

alrighty than

[wampcat1]

Hi Zach,
Have you had any luck locating a schem? I'm not real familiar with that pedal.


Thanks,
Brian

[Dirk_Hendrik]

There's a schem on my site in the techstuff section. Although I should make a newer version which corrects a small error I believe the level control part is correct.

[zacharybroyles]

http://www.dirk-hendrik.com/images/Ibanez_CP9.gif

Brian, theres the schematic thanks to Dirk_Hendrik. Maybe I could just replace the pot with a 100K pot and add a 10K resistor but thing is the way its wired. let me get some more pictures up.

[wampcat1]

http://www.dirk-hendrik.com/images/Ibanez_CP9.gif

Brian, theres the schematic thanks to Dirk_Hendrik. Maybe I could just replace the pot with a 100K pot and add a 10K resistor but thing is the way its wired. let me get some more pictures up.

Hey Zach,
Have you already checked all the components, solder joints, etc to make sure everything that is visible is ok?

Thanks,
Brian

[Paul Perry (Frostwave)]

Looking at the schem, if the level pot is doing "something but not much" the likeliest thing is, the connection between the pot and the 10K is broken, or between the 10K and ground. Or maybe the connection between the pot element and the leg that connects to the 10K is bad.

[zacharybroyles]

http://www.guitarpedalmods.com/images/100_0622.jpg The pot itself
http://www.guitarpedalmods.com/images/100_0623.jpg How the pots hooked up
http://www.guitarpedalmods.com/images/100_0629.jpg Back of the board
http://www.guitarpedalmods.com/images/100_0630.jpg Top of the board

all the wires on the pot are connected, all the wires running from the pot are connected soundly to the board ( i pulled them ), no parts looks bad or dissconnected as far as I can tell. do you think i should try replacing the pot and seeing what happens? I would send this to someone if they could fix it because I'm at a loss.

[zacharybroyles]

Looking at the schem, if the level pot is doing "something but not much" the likeliest thing is, the connection between the pot and the 10K is broken, or between the 10K and ground. Or maybe the connection between the pot element and the leg that connects to the 10K is bad.

look at that picture I posted of the pot, its like there are two pots stacked together. one being the 10k the other being the 100k.the pot give a boost in volume but its extremely slight, maybe this is how this pedal works?!?!? I've never used one untill i got this one.

[zacharybroyles]

and whats up with the stuff on the back of the board, think that is a mod done by someone, i thought it was but the resisitors look just like the rest on the board....ahhh  wait, no looked at the schematic looks like that stock

[zacharybroyles]

any more ideas guys

[johngreene]

the picture of the pot in question is the attack time pot, not the level pot according to the schematic. And if my eyes aren't fooling me, which they probably are, the electrolytic cap above the IC looks like it has a bad solder joint. Looks like it's just a bypass cap to ground though.

--john

[zacharybroyles]

Hmmm, i'll warm up the soldering gun and hit the leg of that cap, maybe someone swapped out the attack and level pot since this pedal was made. If thats so then the attack pot doesnt do very much but I heard it doesnt make a huge difference anyway. I'll check that cap out. Thanks so much.

[Dirk_Hendrik]

and whats up with the stuff on the back of the board, think that is a mod done by someone, i thought it was but the resisitors look just like the rest on the board....ahhh  wait, no looked at the schematic looks like that stock

Take care.

The schematic was taken reversed from a CP-9 with exactly the same mod. Most likely every CP9 has this mod. I don' think the pots were swapped earlier. This from the simple assumption that it's close to impossible to find a dual pot with different resistance values unless ordered custom.