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Roland JC50 trouble

Started by Warwick720, July 09, 2014, 05:28:16 PM

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Warwick720

Hello! After searching around for a bit and taking a look at my Roland JC50, I can't figure out what's wrong with it. One day, I was foolishly trying to keep up with a loud band with my little amp, and foolishly kept the volume at max for a little too long.  ::)

The pilot light still works, but there's no sound. The first thing I checked was that the connections to the speaker considering there isn't even hiss with the volume up, but they're fine. The only thing that looks out of place inside the amplifier is one detached reverb spring, but that shouldn't cause problems with anything but the reverb, no?

Any ideas as to what could be the problem? Any help would be greatly appreciated.

Thanks!
Preston

ilyaa

you check if the speaker(s) are blown?

if you have a multimeter you can just put it across the speaker tabs and see that it gives you somewhere in the vicinity of speakers' impedance (8 ohms/4 ohms/whatever they are).

if you dont have a multimeter you can get a 9V battery and use a couple of clip leads. attach one clip lead to the positive battery terminal and one to the negative battery terminal. then briefly touch those clip leads to the speaker tabs - one to each. the speaker should make a little sound as if its pushing a tiny bit of air out (low-ish sounding rustle). if it doesnt make any sound at all you can be sure its blown.

Enzo


Warwick720

If the speaker was just blown wouldn't it just sound bad, rather than being silent? I'll check with a multimeter next chance I get.

I checked the fuse right away, but I figured the pilot light wouldn't work if the fuse was blown. Looked fine, replaced it anyway. Still nothing.

J M Fahey

There´s blown and blown.
There´s different types of failure.
The voice coil might have opened in which case it would be mute, or partly unglued, bubbled, have loose windings, etc. in which case it would sound bad.