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Peavey Valverb


 
12/6/1999 5:03 PM
John DeLuca
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Peavey Valverb
Hi,  
I have a Valverb (8 knob model). Decent sounding, but there is a noticeable drop off in the volume when the trem circuit is engaged. Anyone have similar experience? If so is there a fix?  
 
Thanks,  
John  
 
12/12/1999 6:12 AM
John DeLuca
Hi,  
 
Well I had hoped to find some info. On Harmony Central a reviewer said that a tech fixed the drop in trem volume, but he couldn't remember what he did.  
So, I look for some help with a drop off in output volume when I engage the tremelo. Has anyone else noticied this and fixed it, somehow?  
 
Thanks,  
jd
 
 
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12/13/1999 12:25 PM
Nyquist
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Mine did that as well. I changed the LDR (Peavey ref 70240101) on one of Peavey's customer service guys advice.  
The volume doesn't drop anymore!  
 
Be carefull, it's performance are very easily affected by temperature so don't use a too hot iron.
 
12/13/1999 3:33 PM
John DeLuca
Hi,  
 
Sorry, I'm a bit of a novice. Could you explain for me. I really appreciate it!! Thanks a bunch.  
 
12/13/1999 5:03 PM
Nyquist
email

No problem!  
 
The LDR is a Light Dependant Resistor. The light is driven by the oscilator of the tremolo and the resistor is in the signal path. Its value changes according to the light pulses and attenuates therefore the signal following a patern determined by the oscilator.  
Now, because the LDR is sensitive to heat, it happens that the value of the resistor part (or the quality of its response to light) drifts when the LDR is soldered to the board, creating a loss in volume when the oscilator drives the LDR.  
You only need to change it but make sure you don't overheat it with your soldering iron. I don't know it's commercial or original reference but you certainly can get it from Peavey with the ref I gave you in my last post.  
 
Cheers!
 
12/13/1999 5:48 PM
John DeLuca
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Nyquist,  
 
Thank you very much!!  
 
Back at you!  
 
jd
 
12/14/1999 11:14 AM
Nyquist
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Anytime!
 
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