Problem with Ampeg SVT-2PRO at gig

BigMac5 · #1 08-30-2010, 03:59 PM

Saturday my SVT-2 PRO would not turn on and would just stay in standby mode. THe light would stay red and never turned green.

I tested the amp the next day at home and it turned on with no problems. Any ideas as to why?

BigMac5 · #2 08-30-2010, 05:43 PM

okcrum · #3 08-30-2010, 05:51 PM

Here's one tech's experience with a similar problem:

SVT2-Pro repair notes

maaaaaaaaaaat · #4 08-30-2010, 06:00 PM

Did you leave it sit dor a period of time before switching???

Sometimes i turn the stand by on too fast and what happens is the delay time at the start is reset , which makes you think the amp is not coming on

Mat

DanRJBrasil · #5 08-30-2010, 06:03 PM

maybe the venue electrical

heath_r_91 · #6 08-30-2010, 06:33 PM

I think I remember hearing something about they have a protection circuit that won't let it come out of standby if the voltage that it's plugged in to is too low.

T.A.P Bass · #7 08-30-2010, 07:06 PM

^^ both of the above ^^^

Jerrold Tiers · #8 08-30-2010, 08:02 PM

There is no specific voltage sensor in the SVT-2PRO.

There is a connection from the DC part of the filament supply to the relay on the AC connection board. If teh DC filament supply is not there, or I suppose, if teh Ac line is crazy low, the erlay may not let it go out of standby.

The same fix as for the VR will work (same AC board), but I would suppose the problem is a lot less common with the 2PRO.

BigMac5 · #9 08-30-2010, 10:14 PM

yeah, they were powering everything off a big power generator at the festival.

johnk_10 · #10 08-30-2010, 10:17 PM

Quote:

Originally Posted by BigMac5

yeah, they were powering everything off a big power generator at the festival.

i think that was your problem. i'm always very cautious of running an amp off of a genrator and generally recommend against it, since i've had to repair way too many amps fo rmy customers that were blown up as a result of it.

marklaforest · #11 08-31-2010, 12:01 AM

Yeah, I've had issues with generators and things like digital keyboards and older tube amps. The generator doesn't always output at a steady rate. One solution is to get a power conditioner and always run that before your equipment. You don't necessarily need a crazy rack mount Furman or anything, you can get decent ones that are built into power bars that get the job done.

johnk_10 · #12 08-31-2010, 12:08 AM

i'd feel alot more comfortable running a generator into a voltage regulator and then into my amp. something like this:

http://www.furmansound.com/product.p...01&id=P-2400AR

or this

http://www.furmansound.com/product.p...1&id=P-3600ARG

Jonyak · #13 08-31-2010, 05:42 AM

Quote:

Originally Posted by marklaforest

Yeah, I've had issues with generators and things like digital keyboards and older tube amps. The generator doesn't always output at a steady rate. One solution is to get a power conditioner and always run that before your equipment. You don't necessarily need a crazy rack mount Furman or anything, you can get decent ones that are built into power bars that get the job done.

I was playing an outdoor festival running off a generator, playign a 5 string. I hit the low B and all the keyboardists equipment turned off.

haha.

Bluesbob · #14 08-31-2010, 08:18 AM

Quote:

Originally Posted by Jonyak

I was playing an outdoor festival running off a generator, playign a 5 string. I hit the low B and all the keyboardists equipment turned off.

haha.

That's funny! Would've loved to see it.

rbonner · #15 08-31-2010, 08:30 AM

Playing outdoors is generally a nightmare no matter what way you look at it. Sun in your eyes, too hot, rains, bugs and too long of extension cords, shaky stages and BAD POWER.

Unless it's a totally professional festival with BIG POWER you are at the mercy of marginal equipment.

For instance. I have a nice 5KW generator that will power a normal sized band, no lighting, very adiquately. I have run Solid State gear on it, I have used it in operations that required it to run almost all of 24 hours. Great rig. I trust it. I also own it and maintain it.

I have also done several operations where I had equipment fail due to marginal generators back int he 70's and 80's.

One of the best thought out ops I brought one of my big server UPS's along. A big APC unit. When the gen even went down for gas the equipment stayed running.

BOB

BigMac5 · #16 03-22-2011, 10:02 AM

I found pout what was wrong with the amp. As it turns out it was a bad power tube that was acting up.