Amp fell from a chair, can/should I fix it?

Tommy el Gato · #1 11-05-2012, 08:05 AM

I was in a rehearsal for a jazz recital at my college campus when my amp, a Roland Cube 100 which I normally elevate to reduce feedback with the Double Bass, fell out of the chair. It didn't switch off or anything like that and continued to work. However, when I came back later that day to do the soundcheck, I go to flip the switch and the LED's power up, but the normal "click" that happens about 4 or 5 seconds after I flip the switch never happens and I don't get any sound whatsoever from the amplifier.

So, I'm wondering if anybody knows what I broke and if it's going to be a big deal to fix.

Bassmec · #2 11-05-2012, 08:13 AM

Quote:

Originally Posted by Tommy el Gato

I was in a rehearsal for a jazz recital at my college campus when my amp, a Roland Cube 100 which I normally elevate to reduce feedback with the Double Bass, fell out of the chair. It didn't switch off or anything like that and continued to work. However, when I came back later that day to do the soundcheck, I go to flip the switch and the LED's power up, but the normal "click" that happens about 4 or 5 seconds after I flip the switch never happens and I don't get any sound whatsoever from the amplifier.

So, I'm wondering if anybody knows what I broke and if it's going to be a big deal to fix.

It should be an easy fix, it will be something heavy has just broken its solder joint, not to hard to find at all for an experienced bloke.

jlepre · #3 11-05-2012, 08:29 AM

or it could be something worse like a circuit board. Take it to a professional.

craig.p · #4 11-05-2012, 08:55 AM

Open it up and have a look around for things that don't look right. Re-seat all connectors, snug up all screws, check for loose bits, all the commonsense stuff. If it's a combo, check that the speaker wires are still attached (and that the magnet didn't fall off the speaker basket).

If still no joy, THEN take it to a tech.

jlepre · #5 11-05-2012, 10:31 AM

as long as this amp isn't under warranty. Sometimes just opening it will void that warranty. If NOT still in warranty, then open her up and have a look.

ddnidd1 · #6 11-05-2012, 10:32 AM

Quote:

Originally Posted by craig.p

Open it up and have a look around for things that don't look right. Re-seat all connectors, snug up all screws, check for loose bits, all the commonsense stuff. If it's a combo, check that the speaker wires are still attached (and that the magnet didn't fall off the speaker basket).

If still no joy, THEN take it to a tech.

If the OP hasn't already thought to do that, the troubleshooting/repair probably shouldn't be attempted. Take it to someone who knows what they are doing.

Just the way the OP framed the question says 'take it to a tech'.

Tommy el Gato · #7 11-05-2012, 10:49 AM

Yeah, this amp is extremely hard to open up. I've tried to do it before and it seemed like the speaker cable was so short that it prevents removing the head from the speaker enclosure. That's not to mention, this thing is one of those newfangled digital thingies and so I have no clue if I the problem would be visible inside the amplifier the way it would be in an analogue amplifier.

I suppose I was hoping there was a wealth of people on TB who know exactly what goes on in the power-up sequence of these digital amps and knows "when the click doesn't happen, part x is loose/broken and fixing that is expensive/inexpensive/impossible."

ddnidd1 · #8 11-05-2012, 11:05 AM

FWIW here's a link to a schematic. EDIT: Crap. This is a schematic for a 60. A Service Manual exists, but so far I can't find a download.

http://music-electronics-forum.com/a...nd-cube-60.pdf

EDIT:
Found the Cube 100 Bass Service Manual: http://www.eserviceinfo.com/download.php?fileid=50935 This is free. It includes a disassembly diagram and instructions for running a Test Mode diagnostic.

You can get a hardcopy on EBAY for $30 ! But it is leather bound.