20 Most Recent SWR WorkingPro 15 200 Watt 1x15" Bass Combo Amp Questions & Answers

I have found a site with SWR schematics: They have one for the SM400 which may be very close to what you have, or at least parts may be the same.


SWR WorkingPro... | Answered on Dec 19, 2013

Try the link below to locate your local supplier.


SWR WorkingPro... | Answered on May 26, 2011

If you are having the treble/high turned up there will be hiss. This is due to the statistical noise in electronics, including semiconductors. It is a matter of degree. The hiss should be 30 Db below your program level or so.

It is very common for one to change settings and suddenly start to notice hiss or hum at certain settings.

IF YOU CAN, go to a music store and COMPARE the amp to yours at the same setting with NOTHING plugged in. (cables and guitars can generate hiss or other noise themselves).

There is very little in your amp that would have changed to suddenly start generating hiss, so FIRST compare. This will minimize the chance of spending money at a shop to be told it is normal.

SWR WorkingPro... | Answered on Sep 15, 2010

Since the PA clip is not lit, the problem seems to be up front...

First thing is to look for a bad cable as a broken ground could be putting hum at a clipping level. First thing, test this by unplugging all inputs. If the clipping light goes out, then you have bad cables or a ground loop.

Try sending a line level signal into "Effects return" to test if the power amps are OK.

If the clip light is still on, turn all gain controls down to minimum. If light is still on then take unit for servicing.

SWR WorkingPro... | Answered on May 31, 2010

If you can find a schematic that will answer your question. You can also open the unit and see if there are two or four wires associated with the input power to the transformer. Some can be strapped for either voltage. Finding a replacement transformer would be a real problem.

Another option would be to make an autoformer convertor using a 150 watt control transformer and use only the primary. In autoformer mode, the external transformer needs to be only half the power input sixe so a 150 watt would work. Feed the power to one of the two primaries and put the second in series to add to make 240.volts. They are a little heavy but not that bad. About half the size of a small loaf of bread. These are OFTEN available surplus for cheap.

SWR WorkingPro... | Answered on Jan 18, 2010

I don't have a exact schematic for your amp, but I can give you some hints and suggestions...

USUALLY when the output transistors fuse there is a problem at least one level back and sometimes two levels. Often the driver transistors also get fried and sometimes one stage farther where the bias is regulated for the final amp transistors. A schematic is imperative to diagnose and repair unless one replaces every part.

Next, to prevent damage when restarting the amp, put a 100 Watt incandescent lamp in series with the hot power into the unit. This acts as a current limiter and auto-resetting fuse. The lamp will come on and limit the current while one troubleshoots the amp to find what is causing the current drain.

This schematic MIGHT be pretty close to your unit:


I would expect to see Q4 through Q12 destroyed and maybe a few more components. If transistor Q4 opens, goodbye all the transistors! The 1N4004 diodes are PROBABLY big enough to take it, but all the small transistors probably are damaged or degraded... The high value resistors will survive, but the low ohm ones that can draw enough current may be damaged.

Try to analyze what each part of the circuit is for... I think Q13 and Q14 are part of a soft start circuit. This amp is NOT well protected in case of component failure and MANY that fail in the final stages cause catastrophic destruction.

Use my suggestion for the lamp. Often using a Variac to slowly bring up the voltage is handy, but one doesn't only have one available.

SWR Music | Answered on Mar 05, 2011


Music | Answered 12 hours ago

Last post will not let me put pictures for some reason so mine says Ibanez 61-12491

Music | Answered on Jan 09, 2021

Just add some adhesive Velcro (hook and loop fastener) The industrial rated for 25 pound should be good for most players, 75 pound rated minimum for Jerry Lee Lewis type players.

Set the stand at the height you want, put the hook tape on the stand leg top and then target the fuzzy strip to the piano. Be aware the pound rating is rated per square inch- so you will want to put a 10 or 12 inch strip of fuzzy on the piano, and 1 or 2 inch strips on the stand leg.

Music | Answered on Dec 20, 2020

This is a common problem with Bugera. And, unfortunately they are made by Behringer who is known to have the worst customer service of all and do not follow through on their warranties.

Music | Answered on Dec 12, 2020

Request the manual from Rogue.

Music | Answered on Dec 07, 2020

It's here $16.15

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Music | Answered on Dec 02, 2020

I suggest checking to make sure those 2 units can actually use the same adapter and also check the polarity on both to see if they are the same. Most stompbox stuff usually has negative on the center of the socket, instead of positive like other devices. If I spend a little time I could find the manuals and find out for myself but, this was my logical "top of my mind" kind of advice. Those values (volts,mA, and polarity) must be known in order to help you further. I believe it will be 9v, a few 100 mA's, and negative in the center on both but, not sure.

Music | Answered on Nov 25, 2020

Contact Clavinova directly to request the manual.

Music | Answered on Nov 11, 2020

Did you get it fixed?

I have exactly the same problem!

Music | Answered on Oct 26, 2020

hi becky
from looking up the model some of the prices were only 30.00 to 40.00 dollars needing repairs other units/ models went higher in price depending on model and if they where in good repair.
so the decision for u would be is this the organ that you want to restore or do you want to look for other units?

Music | Answered on Oct 23, 2020

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