Genz Benz Shuttle Troubleshooting

topper · #1 06-10-2010, 06:22 AM

Hope you can help me here.

I've got a Genz Benz Shuttle 6.0 and it started acting up last night at practice.

I set up, plugged in and played for about 5-10 minutes when my volume dropped and I lost a lot of high end. It pretty much behaved exactly like a dead battery with active pickups.

So I turned off the amp, swapped the battery in my bass, plugged back in and turned on the amp.

Everything was fine for about 20 minutes then it happened again. I shut off the amp, waited a minute, turned it back on.

I was good for another 20 minutes or so and it happened again.

I turned the amp off, back on, fiddled with the preamp controls a little and then had no further problems for the rest of practice (about another hour).

Any idea what this could be?

craig.p · #2 06-10-2010, 08:41 AM

Just off the top of my head, that almost sounds like a power-starvation problem. Are you following "best practices" when it comes to your AC supply?

Another possibility would be a flaky speaker cord.

Another possibility would be a voice coil deforming (and changing impedance in the process). Were you playing really loud, possibly louder than the cab could handle?

I admit these are just total SWAGs. But gotta start somewhere...

esoxhntr · #3 06-10-2010, 09:02 AM

E-mail Genz Benz immeditately! Possibly the best customer sevice on the planet, and you'll get help within minutes.

topper · #4 06-10-2010, 10:17 AM

Quote:

Originally Posted by craig.p

Are you following "best practices" when it comes to your AC supply?

I'm not sure what those would be. Plugged into the same outlet I always plug into. No one else in the room (probably all on the same circuit) had this problem.

Quote:

Originally Posted by craig.p

Another possibility would be a flaky speaker cord.

Hmmm... I guess that's possible but seems unlikely. This is the genz combo with the 112T.

Quote:

Originally Posted by craig.p

Were you playing really loud, possibly louder than the cab could handle?

No, if anything I was playing much quieter than usual.

topper · #5 06-10-2010, 10:18 AM

Quote:

Originally Posted by esoxhntr

E-mail Genz Benz immeditately! Possibly the best customer sevice on the planet, and you'll get help within minutes.

Yeah, I'll do that later today. I know a few of their guys routinely check this forum. Was hoping to catch them here.

craig.p · #6 06-10-2010, 11:34 AM

> Plugged into the same outlet I always plug into. No one else in
> the room (probably all on the same circuit) had this problem.

Have any of the other members changed their amps to ones that draw more current?

Has anything else been added to the same circuit (i.e. same breaker, which could fan out to more than one outlet)?

Have you guys recently started using the A/C?

The fact that others don't have the same problem with their amps is interesting but probably n/a unless they're running the same make & model amp you are.

I'd run a long extension cord (a good one with THICK conductors) off to another outlet on another breaker that isn't seeing much of a load. If the problem goes away, you've got your answer. Or you can meter out the circuit you're using but it has to be done while everyone's playing at full volume because that's when the voltage sag (if there is any) is going to occur.

svtb15 · #7 06-10-2010, 11:49 AM

Try running a 1/4 inch jack in and out of the EFFECTS LOOP on the rear a few times.. Sometimes there will be contamination in there that will break the contact between the Preamp section and the Poweramp section...

Run the 1/4 in and out a dozen or so times in those EFFECTs Send Receive on the rear..

topper · #8 06-10-2010, 12:02 PM

Quote:

it has to be done while everyone's playing at full volume because that's when the voltage sag (if there is any) is going to occur

Well that rules that one out. It wasn't happening when we were playing at full volume. It happened when I was pretty much the only one playing.

svtb15 · #9 06-10-2010, 12:05 PM

Try running a 1/4 inch jack in and out of the EFFECTS LOOP on the rear a few times.. Sometimes there will be contamination in there that will break the contact between the Preamp section and the Poweramp section...

Run the 1/4 in and out a dozen or so times in those EFFECTs Send Receive on the rear..
Let us know what happens

Quote:

Originally Posted by topper

Well that rules that one out. It wasn't happening when we were playing at full volume. It happened when I was pretty much the only one playing.

hasbeen · #10 06-10-2010, 02:14 PM

thanks for the assist Kirk.

Yes, do what he says- run a 1/4" plug in and out, in all the jacks a couple of times....even the effects loop. If there is anything in there...oxidization and such, this will clean it out.

If that doesn't work, give us a buzz.

Is the amp new?

topper · #11 06-11-2010, 05:11 AM

Quote:

Originally Posted by hasbeen

Yes, do what he says- run a 1/4" plug in and out, in all the jacks a couple of times...

Is the amp new?

I bought it used, not sure of the actual age. I'll try the 1/4" jack thing. Thanks for the help.