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Peavey classic varying volume output


 
3/29/2006 12:37 AM
Fred
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Peavey classic varying volume output
Hello all,  
 
I have an strange problem with my Peavey Classic 50 combo.  
When i play loud (pos 5-10) after some time the output power drops.  
 
Next day when i play at modest level (pos 1-2) everything sounds OK again.  
 
Last time at rehearsing my amp got warm started to smell and my fuse melt.  
 
I'm suspecting very bad cooling design of my classic 212/50 combo.  
 
Any ideas very welcome!  
 
Fred
 
3/29/2006 9:51 AM
Fred
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Maybe this is an very easy one, i'm a newbie.  
 
 
Anyone?  
 
Thanks,  
Fred
 
3/29/2006 4:59 PM
KB
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Change your power tubes Fred and try again. Hopefully you didn't fry an internal fuse or a transformer but it sounds like power tubes.  
 
KB
 
3/29/2006 6:54 PM
Enzo
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It has a cooling fan, is your fan running?  
 
I vote tubes as well, how old are your power tubes?
 
3/29/2006 11:52 PM
Fred
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Thanks for your first ideas,  
 
Well, the fan is spinning. I recently made an silent PC. As from what i see on the internals of the Peavey, i see quite poor cooling for the tubes. Maybe the cooling is only intended for the other parts?  
 
The tubes are five years old.  
How long do they last?  
 
Fred
 
3/30/2006 8:58 AM
Fred
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Hi all!  
 
I checked today for new tubes(type EL84). I can buy them seperately or by matched pairs.  
What to choose?  
 
Thanks  
Fred
 
3/30/2006 5:58 PM
Enzo
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Buy the EL84s as a matched quad. You could use two pairs, but any good tube seller puts up quads as well. Contact Bob at Eurotubes or use one of the suppliers that advertise on thios web site in the margins.  
 
5 years old tubes? My god, that would be about like 5 year old guuitar strings. For someone who gigs - plays a few hours every night - I expect maybe a year from a set of EL84 at best.  
 
The cooling is for the tubes, not the other stuff. it needs to keep them from burning up, they don't want to actually be kept cool. As long as the fan is running and the vent not blocked, that system works fine. Main complaint is in recordign sessions, sometimes you can hear the fan.
 
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