Ampeg SVT 2 Pro problem

[tuss]

My SVT decided to stop working at my last gig. Fortunately the DI out still worked so was able to continue with gig through PA and monitors, but nothing coming through the cab. Turned amp off for awhile between sets to let it cool down, and when turning it back on initially seemed fine, but within a few seconds it stopped working again. The green light on front starting flashing. I'm presuming that it's probably time to replace the power tubes(6550)? I do recall at the start of the evening turning on the amp, not realising that the speaker cable was not plugged into the cab, so wondered whether that may have caused the fault.

Any advice would be welcomed.

Rob

[BOD2]

From the Ampeg manual -

[url="http://www.ampeg.com/pdf/SVT-2PRO.PDF"]http://www.ampeg.com/pdf/SVT-2PRO.PDF[/url]

"16. STANDBY/POWER/FAULT INDICATOR LED: This is a multi functional LED. In Standby mode, it glows red. In the On mode (when the high voltage comes on) it glows green. If it does not turn green in the On mode, there is no high voltage present and the unit needs servicing.

If the amp detects a fault in the power tube circuit, the high voltage is turned off and the LED flashes between red and green. This usually indicates a bad power tube. The amp will remain in this condition until the unit is turned off."

If you've got a flashing red/green LED then it does suggest a problem with the power valves.

[Guest]

I feel your pain Rob,i have just been quoted £180 for a set of valves for my V4. The up side is it could sound better once fixed

[tuss]

[quote name='BOD2' post='506249' date='Jun 5 2009, 12:00 PM']From the Ampeg manual -

[url="http://www.ampeg.com/pdf/SVT-2PRO.PDF"]http://www.ampeg.com/pdf/SVT-2PRO.PDF[/url]

"16. STANDBY/POWER/FAULT INDICATOR LED: This is a multi functional LED. In Standby mode, it glows red. In the On mode (when the high voltage comes on) it glows green. If it does not turn green in the On mode, there is no high voltage present and the unit needs servicing.

If the amp detects a fault in the power tube circuit, the high voltage is turned off and the LED flashes between red and green. This usually indicates a bad power tube. The amp will remain in this condition until the unit is turned off."

If you've got a flashing red/green LED then it does suggest a problem with the power valves.[/quote]


The LED just flashes green, but then it is a 90's SVT so maybe he green/red flashing wasn't introduced back then.

[wizbat]

Powering up the amp without the speaker connected is probably what did the damage, tranny amps are usually ok when doing this but with valves it,s a big no no!.

[tuss]

[quote name='gareth' post='509335' date='Jun 9 2009, 05:59 PM']I had the same problem with my SVT pro II when I first got it, about a year ago.

I did two things:-

1. EMS serviced it - mainly re-attaching valve seats, etc.

2. I then re-valved it myself with Electro-Harmonix 6550's which I got for £110 for 6 on ebay.

Since then it has worked faultlessly.[/quote]

Have since replaced the Svetlana 6550's with Electro-Harmonix valves, and problem solved; amp sounds great now. Thanks for the advice.