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Hoffman Amps Forum image Author Topic: IRF820 REVERB FX  (Read 4710 times)

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Offline TIMBO

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IRF820 REVERB FX
« on: August 05, 2012, 02:32:47 am »
Hi guy's, This circuit works very well, so if you need a reverb that sounds as good as tube (to me it sounds as good) and plenty of verb without the mAs this this is perfect. There is a small amount of hash when the level is turn up, but when a 500p cap(C6) is added (not on the original circuit) it did reduce the hash quite alot.

A couple of things:-
If the LEVEL pot is on "0" it kills the sound of the amp (normally with a tube reverb) the sound will pass reguardless of the level position.Also in a tube reverb there would be a 330k on the wiper of the level pot ,would this help as i would like it to pass signal reguardless of the level position.  :icon_biggrin:
The circuit seems to add some boost,this means that when the level is turned up it gets a little distorted, i thinking that a larger pot may be needed as in the tube reverb it has a 1M pot for the level. Any thoughts???
The bold voltages are what i have and the lite voltages are the original,as you can see i'm running at a lot lower voltages but sounds great so i'm happy to keep then as is,or is running at lower voltages adding more gain  :dontknow:
The hash is the same as what i call SS hash so i don't know if there is much that can done to eliminate it  :dontknow:
Some more tweaking to be done,some more input would be great.Thanks 

Offline sluckey

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Re: IRF820 REVERB FX
« Reply #1 on: August 05, 2012, 08:03:18 am »
Quote
a 330k on the wiper of the level pot ,would this help as i would like it to pass signal reguardless of the level position.
yes
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline tubenit

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Re: IRF820 REVERB FX
« Reply #2 on: August 05, 2012, 08:32:18 pm »
Hey Timbo!  Thank you for sharing this!  It is appreciated.

with respect, Tubenit

 


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