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Ampeg SVT 2 Pro gets really hot
- Thread starter Mik75
- Start date
When you are dealing with six 6550s a couple of inches is not all that much. A high power tube amp NEEDS ample room to allow the heat out. If it's not there then the amp cooks itself leading to premature failure.
The only time my 2 Pro shut down was at an outside gig, probably around 100 degree outside temp. I took it out of 4 space shock case and finished the gig, without having to replace any fuses. That was a few years ago, hasn't shut down since; still haven't replaced any fuses. There must some kind of protection in the SVT 2 Pro. Seems like I have read about it somewhere. Probably here.
Yes the 2Pro has the fault/shut down mode - usually activated by a faulty power tube (just like the SVT - CL). I don't think the SVT II non pro has this safety circuit. I don't know if this fault mode is related to tempeture or not.
On a different subject, I would not install a 70 pound SVT into a rack that did not include support other then the four faceplate bolts. There are four inserts in the bottom of those amps that should also be bolted down.
In my experience, an added fan is helpful with the rack mounted svt's. The traditional style SVT heads all have bigger fans stock.
On a different subject, I would not install a 70 pound SVT into a rack that did not include support other then the four faceplate bolts. There are four inserts in the bottom of those amps that should also be bolted down.
In my experience, an added fan is helpful with the rack mounted svt's. The traditional style SVT heads all have bigger fans stock.
Hi there!
I played the amp without the rack and without an additional fan, and it still got quite hot. I could lay the hand on top of it, but it became quite unfomortable after a few seconds. So, tomorrow I'll try to use it in the case again, but this time with a 12v PC case fan. I ordered a high quality one, but unfortunately, it will be delivered next week. So I took an old one I had in an older PC build, and I am not sure about its rpm. But the first test (without the Gator case) showed promising results! I'll run that setup at a gig tomorrow night!
I played the amp without the rack and without an additional fan, and it still got quite hot. I could lay the hand on top of it, but it became quite unfomortable after a few seconds. So, tomorrow I'll try to use it in the case again, but this time with a 12v PC case fan. I ordered a high quality one, but unfortunately, it will be delivered next week. So I took an old one I had in an older PC build, and I am not sure about its rpm. But the first test (without the Gator case) showed promising results! I'll run that setup at a gig tomorrow night!
I still think there is something wrong with the amp. Supplemental cooling is a good thing but the fact that it got super hot outside of the case in stock trim points to a problem with the amp itself.
Before it went to the tech, it was fine. Afterwards, it's now hot. Pretty clearcut cause I would think. I would take it back to the tech in stock trim without the fan and troubleshoot the cause of the excessive heat.
Before it went to the tech, it was fine. Afterwards, it's now hot. Pretty clearcut cause I would think. I would take it back to the tech in stock trim without the fan and troubleshoot the cause of the excessive heat.
I sometimes use a small tiltable desk fan such as this Honeywell HT-900 gently blowing onto the back of the amp to help circulate the air. I makes a difference.
It helps to position the amp away from a wall or corner so that air can circulate around the back.
It helps to position the amp away from a wall or corner so that air can circulate around the back.
I really trust this tech. Before the overhaul it didn't get that hot, but it didn't get that loud as well. The bias had been completely off with the old unmatched tubes. Now, the amp shows its full potential, it's loud and it produces a tone to die for. That healthy tone alone shows me, that this amp must be technically ok! I read many posts about insufficient cooling on the SVT-2 pro. The Classics, Heritage, etc. heads in the wood cases have better cooling! I'll report back here with the results from the next (loud) gig tomorrow! (my guitarist plays a Marshall JMP, and he likes to play it loud! ;-) )
Tube amps get hot. Once fully warmed up I'm not at all surprised that you didn't want your hand on top of it for more than a few seconds.
An SVT has 6 big bottles that get really hot...
An SVT has 6 big bottles that get really hot...
^ yep, it's going to get hot. especially after playing it hard. my svtII is the same, the top of the case over the power section gets pretty hot, no it won't blister my hand or anything but it also is not comfortable to hold my hand there.
if i let it idle for maybe 10 minutes it cools down to just warm...it also sounds better once it get up to that really hot running temp.
if i let it idle for maybe 10 minutes it cools down to just warm...it also sounds better once it get up to that really hot running temp.
The CL, VR, and vintage amps have a fan that pulls/pushes air across the tubes and transformers. The rack mount SVT- 2/pro amps have a small fan tucked in a corner that almost looks like it blows into the bottom of the chassis (based on images I've found online, see below). I'm really not surprised there is more issues with the 2/2pro
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I owned number 247 from 1994 (purchased it new) until early 2009.
I found the stock cooling system to be insufficient. Almost from the beginning I had used an additional fan (I had purchased this amp to replace my vintage SVT that was stolen from me - which of course had the big fan in the back). The Pro-2 definitely ran hotter than my vintage SVT. At first I used an exterior appliance similar to the fan the Beans posted - but mine had a clip for a base and I would connect it to my 810's towel bar. It fell off a couple off times, so I purchased a 4 inch cooling fan from Radio Shack and screwed it on the back. At some point I figured I would never sell the amp (best sounding amp - ever), so I cut a hole in the top and re-installed the fan there (with no regard to the mod's effect on resale value). I also vented my homemade rack enclosure in the top. The faceplate of the amp went from too hot to hold your hand on, to a comfortable warm that you could rest your face on while you rocked out if you wanted to
It may be worth a try to call Ampeg and see if you can get a replacement top - then cut away (I don't think venting the rack would be necessary).
I found the stock cooling system to be insufficient. Almost from the beginning I had used an additional fan (I had purchased this amp to replace my vintage SVT that was stolen from me - which of course had the big fan in the back). The Pro-2 definitely ran hotter than my vintage SVT. At first I used an exterior appliance similar to the fan the Beans posted - but mine had a clip for a base and I would connect it to my 810's towel bar. It fell off a couple off times, so I purchased a 4 inch cooling fan from Radio Shack and screwed it on the back. At some point I figured I would never sell the amp (best sounding amp - ever), so I cut a hole in the top and re-installed the fan there (with no regard to the mod's effect on resale value). I also vented my homemade rack enclosure in the top. The faceplate of the amp went from too hot to hold your hand on, to a comfortable warm that you could rest your face on while you rocked out if you wanted to
It may be worth a try to call Ampeg and see if you can get a replacement top - then cut away (I don't think venting the rack would be necessary).
The funny thing is - I think it stayed like that until the amp was discontinued.
Go figure.
On the other hand, this particular amp worked flawlessly for 2 decades (as far as I know), and my tech said, that its current condition would be very good. But I'll feel better if the amp runs a little cooler and my Gator case doesn't get melted! ;-)
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Even still, the power supply capacitors and other components will last longer and perform better in a cooler environment. Specifications go down as the temperature increases. If the Gator case is getting soft, you have an issue. Maybe Gator sells a vent for their product that you can install.
There are other case vents sold here:
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There are other case vents sold here:
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Thanks for your effort!
I'll have two more gigs on this weekend and I'll report back here with the results. I really hope that the additional fan I've installed is the key to a cooler amp! ;-)
I'll have two more gigs on this weekend and I'll report back here with the results. I really hope that the additional fan I've installed is the key to a cooler amp! ;-)
