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Ampeg svt4 cuts out....Overheating?

Just got an Ampeg SVT-4 and I have it mono bridged into a 410HLF. I put the amp in a rackmount case with conditioner, tuner. So at first band practice it would cut out periodically. There would be no sound whatsoever for a minute or so. Checked cables batteries etc. I know that there are vents on the back and sides, but it got really hot to the touch. Could it be overheating? Its made for a rack so....?? Any help would be greatly appreciated!
 
Let's not start the overpower underpower thing again.....the 410hlf can handle 1000 watt peaks with 500 watts continuous. The SVT 4 PRO bridged into the 410hlf will work just fine as long as you don't go crazy with the low end boosting and volume levels

Try taking the 4 PRO out of the rack and see if the amp stops getting so hot - it may just be fixed right away. It may be overheating, even though it's a rackmount design, it has side vents which are quickly blocked by most racks out there. Some people have had problems with this, while others have been running it rackmounted and never did have a problem. Some installed vents on the rack unit, and some added a portable fan in the back.
 
Thats a great answer thanks. The top gets so hot its hard too keep my hand there. Pretty hot. So if it was overheating, the result would be the drop out...then resumes by itself in about a minute...? I would love to hear how fans or side vents have worked out for people.
 
Your amp has a problem, it's not normal that it gets hot like that, unless you are cranking it ridiculously and that the warning ligths on it are flashing like a christmas tree.

I had an Svt-4 for 2 or 3 years and it never got really hot. It was racked all the time, used for 4 hour long rehearsals and gigs, I never ever had a trouble with it.

Don't listen to the people telling you to drill holes in your rack or to add a fan, it simply is not normal of your head to overheat like that.
 
Racks are notorious for overheating 4PRO units...... Some have less than an inch of clearance, which pretty much shuts off airflow, which the 4PRO has to have to stay cool.

The 1 minute drop-out is pretty typical of a heatsink overheat situation. if it were the transformer overheating, it would be off for more like 20 minutes.

The question is why it overheats...... The rack is a very likely cause, so take it out and see if it is fine then.

if so, vent the rack.

If not, there is an issue with the amp, probably it is biased a little hotter than it should be.

But I don't think you will have a problem once it gets decent airflow.
 
I had a similar problem but my SVT4 wasn't running hot nor was it in a rack. I had a shop in Portland take a look at it and they re-soldiered some contacts on the preamp and said it was a common problem they had seen with these amps and the cheap contacts being rumbled apart :bassist: That was 4 years ago and I haven't had a problem since.

Sorry to bump an old thread but I came across this looking for a rack case and I thought this might be useful info to someone else.

Kenneth
 
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Drilled 2 pcs. of 3" on each side of the SKB Roller case, giged it last night: no problems.
The complete set got warm (not hot) but that's because a SVT4pro paired with a SVP-pro have about 8pcs of 12AU7/AX-7tubes.
Add up the solid state 1200Watts power amp and the heater is on!!

Cheers,

Theo:hyper: