Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Apprentice on August 22, 2017, 10:11:27 am
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Just finished installing a spring reverb in my Hoffman Blues Junior. I used the Rob Robinette Ss circuit that is basically the blues deluxe circuit and I suppose is designed for a different tank. It works pretty well though. It just has tons of reverb at anything over 0.5 on the pot.
Anyone had any experience of this design. Or any advice to improve the match of this design to the BJ?
I've inserted the circuit at the 220k resistor at master wiper and before phase inverter basically removing 220k on BJ and replacing it with 220k on the circuit below between dry and wet & dry points. I hope that makes sense!
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at anything over 0.5 on the pot.
do you mean 1/2 way to 10, or 1/2 way to 1 :dontknow:
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1/2 way to 1.
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On any Fender reverb circuit (tube or SS) I always use an audio taper pot for the reverb level control as I find the linear taper pots almost always create the same issue you are having.
I added the Blues Jr reverb (different but similar to what you posted) to a 6G2 and had the same issue. Swapped the linear taper pot for an audio taper and it works very well.
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I circled some R's, ohm out n verify they are what the schematic says they are.
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Ok will check the the Resistors and have a go at changing the pot to and union taper. I'm pretty sure the Rs are ok but will check. Thanks for the help
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Agree: check those values. They don't look wrong on the plan. But stuff goes wrong between plan and build. Red-Red-Green is real different from Red-Red-Yellow (how would I know??)
R36 could be reduced from 220K to 100K to 47K, sure.
A properly gained reverb path should not really need an Audio taper, but it sure will make a too-hot reverb more useful.