Gallien Krueger MB115 - NO SOUND - Help?

[danielcostabass]

Hey Guys and Gals,


I'm having problems with my GK MB115 combo I recently got. I used for 2 gigs and a couple of practices and on my 3rd gig with it, it started cutting out on the first song and then it finally got absolutely no sound.

I found a thread about a similar problem but there was basically no solution described on it.

The amp still turns on and the light switch still goes from red to blue. There's a subtle hum when the horn is turned on but no sound on the main speaker.

Another thing I noticed is that the fan is not working, not sure if stopped working with the amp or is actually the cause of it.

The day of the gig, the sound engineer plugged an XLR on it and only got an empty buzz. He then plugged the same XLR on the mic and it worked perfectly so we ruled out the cable. I had no problems with it on the previous shows. Maybe it was a symptom that something was about to happen.

I can't find the fuse on it although there's a sticker saying there is one. I believe it's not the fuse or else I wouldn't even see the light on the power button or even have a little hum on the horn. The circuit would be completely cut if the fuse was blown.

Have anybody gone through the same or similar issue? =PICTURES ATTACHED=


Thank you in advance!

 

[heynorm]

Mine did that a few years back while still under warranty. I think I had the blue light, but no sound. Didn't have time to check the line out or headphone. Luckily an old Kustom was available to finish the gig. The dealer replaced the speaker but I don't remember what the exact cause for failure listed on the repair ticket.

 

[BassmanPaul]

If the amp has an Effects Loop try linking the send and return with a signal cable to see if that helps.

 

[Doug Parent]

Hey Guys and Gals,


I'm having problems with my GK MB115 combo I recently got. I used for 2 gigs and a couple of practices and on my 3rd gig with it, it started cutting out on the first song and then it finally got absolutely no sound.

Old thread I know, but...did you ever ascertain the cause of the problem?

 

[LAPetrarca]

I had the same problem with mine. I don't remember what the part was called but, the tech did tell me that it was the most common part to fail in Class D amplifiers. It took about two weeks to get it repaired. I can't recall how much it cost but, it wasn't outrageous.

 

[Doug Parent]

I had the same problem with mine. I don't remember what the part was called but, the tech did tell me that it was the most common part to fail in Class D amplifiers. It took about two weeks to get it repaired. I can't recall how much it cost but, it wasn't outrageous.

Since you had that repaired has there been any other issues?

 

[LAPetrarca]

No. I kept it for another year and recently sold it to fund a head/cab purchase.