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S/F Pro Reverb with little bottom end


 
10/13/1997 6:33 PM
Doug S/F Pro Reverb with little bottom end
I was lucky enough to purchase a 1978 Pro Reverb that sat in a closet for about ten years. It is cosmeticly in mint condition once I cleaned it up, but has very little bottom end bass response past 4 on the bass control. Is this due to the stock Utah's? Is it due to failed caps? Is it because I'm used to the bass response of my twin reverb (twice the power of the pro)?
 
10/13/1997 8:15 PM
Charles
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It really woudn't hurt to recap the amp, since the things 20 years old, and sitting for that long doesn't help the situation!  
 
After that... you may want to change that cap on the input to the phase inverter to something a little bigger, like .022  
 
Just for grins, you may want to check to make sure the speakers are in phase...  
 
And... past about half way up, the Fender bass control doesn't do too much more. Most of the "control" is in the first half of the rotation.  
 
Hope that helps!!
 
 
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10/14/1997 6:35 AM
dsheppard
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get the O/P tranny changed out to a heftier one....big difference in low end tightness
 
10/14/1997 8:55 AM
R.G.
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Is this a two speaker box? If so, are the two speakers in phase? Out of phase speakers would do what you're describing.
 
10/14/1997 5:43 PM
Doug
Please keep it to a chuckle when I ask what you mean by "in phase", I'm learning as I go! This amp has 2 12" speakers. How do I check that they are "in phase.
 
10/14/1997 9:02 PM
Keith
Doug ,take a 9 volt battery and put your speaker 1/4 plug tip into the the round hole of the 9 volt battery and then ground (at the same time) the shaft of the 1/4 plug to the other terminal so they both touch, look at your speaker cones when you do this ,if both speakers move in the same direction(in or out, preferably out) your in phase, if one speaker moves out and the other speaker moves in your out of phase.
 
10/16/1997 7:10 PM
Doug
It seems they're in phase! I'll start looking at replacing the speakers or getting a cap job.  
Thanks for the help/tip!  
 
DB
 
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