Roland Jazz Chorus 120 Problem

[cg1245]

hello, I posted another forum here about how I couldn't adjust the chorus speed and depth on a 1982/1981 jazz chorus. now, there is another chorus problem where you can hear this distorted noise on the chorus when it is enabled. here is what it sounds like: https://www.youtube.com/watch?v=WuDqi8x3yxE . the problem randomly occurs, like when someone is playing.

also if I hit the amp or turn bright on and off the noise stops and it works just fine.

[cg1245]

also one more thing, when I turn on the distortion, the amp gets a little bit quieter.

[glebert]

I am not sure on an '81-'82, but on my '83 the chorus speed and depth is not adjustable, those only work for the tremolo. Drove me nuts trying to figure out what was wrong, and found out the answer was: nothing, nothing was wrong. My other chorus amps (Fender and Peavey) have adjustable chorus, and the Peavey has adjustable trem and chorus that can be used together (kind of a cool effect).

[Leo_Gnardo]

I am not sure on an '81-'82, but on my '83 the chorus speed and depth is not adjustable, those only work for the tremolo.

Exactly that ^^^. Can't say I've ever seen a JC120 that had controls which adjusted chorus speed and depth. The geniuses at Roland set your chorus so it sounds just perfect for anything. Everybody loves it the way it is. Have you found yet that one speaker has no chorus on it, and the other does? So called "stereo" chorus. If you mic up the plain vanilla one, you won't hear any chorus in your PA or recording. And if you mic up the other it will sound totally seasick .

[g1]

If you hit the amp and the noise quits, then it is a connection issue. Could be a solder connection or a dirty/oxidized pot or switch.
The volume drop when you engage the distortion may be normal, depends how much of a drop and if it can still get full loudness when turned up.

[cg1245]

If you hit the amp and the noise quits, then it is a connection issue. Could be a solder connection or a dirty/oxidized pot or switch.
The volume drop when you engage the distortion may be normal, depends how much of a drop and if it can still get full loudness when turned up.

yeah, when the bright switch is in the off position and i move it up more, the noise stops and you can hear another noise.

[cg1245]

If you hit the amp and the noise quits, then it is a connection issue. Could be a solder connection or a dirty/oxidized pot or switch.
The volume drop when you engage the distortion may be normal, depends how much of a drop and if it can still get full loudness when turned up.

yeah thanks, I took it apart and it turned out all the screws were missing holding down the board. I cleaned out the pots and switches and that seemed to fix it.