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Help! Super Twin Reverb Problem


 
12/3/2005 7:08 PM
lex
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Help! Super Twin Reverb Problem
Hi! i bought an used fender super twin reverb and the guy said that i had to change the tubes, so i did, i put 6 new 6l6 on, and the sound was great for a couple of months, then it got a bit distortioned, and now it sounds awful, i wonder what could it be?? i noticed that i only changed the power tubes and not the pre-amp tubes, could that be the problem?? THANKS!!
 
12/3/2005 7:18 PM
Don Symes
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quote:
"i only changed the power tubes and not the pre-amp tubes, could that be the problem?"
 
 
Possible, not likely.  
 
Can you describe the distortion and when/how it happens?  
 
Does playing with the tone, vibe or reverb knobs change anything much about the distortion?  
 
Does it start distorting at a lower volume than it did??  
 
 
You may find R.G.Keen's Tube amp debugging page helpful.
 
 
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12/3/2005 8:26 PM
lex
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it's a soft distortion but anoying, it happens everytime i'm playing normally, even more when i'm doing something low like an E chord or G. I have to play soft for not gettin it distorted.  
 
No, it's the same thing arranging the knobs, it's always distorted.  
 
The more volume that i set, the more that it distorts
 
12/4/2005 7:12 AM
Regis
Run the amp into another speaker cab to see whether the speakers are blown.  
 
Also, was the amp properly biased when you installed the new tubes?  
 
Does it distort at low volume levels? That is, when the volume on the amp is set at 3 or less, or only when you drive it hard?  
 
Does it do it in both channels?  
 
Eliminate the obvious, try another guitar, cords, take any pedals out of the loop, etc.
 
12/4/2005 8:11 AM
lex
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I have run it into another speaker and it's the same thing.  
 
No it wasn't biased, i don't even know what's that, i was the one who installed them on  
 
no, it doesn't distort at low volume  
 
it has only one channel  
 
i've gotta try with another guitar... i have tried with different cables, without pedals, and that's not the problem. Thank you
 
12/5/2005 2:12 PM
Regis
Go here and read this:  
 
http://www.aikenamps.com/WhatIsBiasing.htm  
http://www.duncanamps.com/technical/lvbias.html  
http://www.aikenamps.com/Why70percent.html  
http://www.aikenamps.com/Biasing.html  
 
In fact, go here and read all of it. You will be better for it:  
http://www.aikenamps.com/TechInfo_2.htm  
 
It seems to me you have bad tubes, but it could be other stuff as well. You need to to take it to an amp tech for diagnosis. If you have any old tubes try swapping them out and see if it makes any difference.
 
12/6/2005 9:10 AM
lex
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ok i'll take it somewhere... thank you
 
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