Redd.47 Output Level Сontrol

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vmanj

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My fixed pad works well in this pattern.
But I would like to make it adjustable..
 

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vmanj

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My modest "knowledge" is only enough to make a preamplifier according to a ready-made scheme, without the possibility of changing something, calculating it myself correctly ..

I was only able to draw a rough outline of what I could see in Chandler's photographs.
Everything is somehow implemented with the least amount of detail ..
If this output attenuator circuit is correct, then I would like to know the values of the resistors (I myself cannot calculate this).
 

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soapfoot

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A Fender Deluxe at moderate volume with a U67 two feet in front of it into your average 40-45dB tube preamp can require 30+dB of pad, so it's a legitimate question to wonder what you're doing when you toss all the gain the preamp is providing, so you can use the preamp.

Sometimes it's artistically desirable to make the preamp distort on purpose, and then attenuate the output.

In particular, two REDD.47s in series with an ES-330 or Epiphone Casino direct in literally is the guitar sound of "Revolution."
 

emrr

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Yeah, I'm using a pre with more pleasing distortion for those moments, usually. A lot of times to my ears the hard clip of higher feedback preamps is better with SS than with tubes. Another consideration.....Revolution is a particular kind of nasty. We're well into YMMV territory with this thought.
 

ruffrecords

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Well, yes, you explain logically, it's hard to disagree with you!

I already have an input pad, but for more versatility, I still want to add a small adjustable attenuator (10dB) to the output, like in Chandler.

Can you please tell me if the scheme (message 49) that I tried to "peep" from the photographs can be suitable for this purpose?
True, I did not succeed in "peeping" the value resistors and the capacitor ..
Yes the scheme in that message should work. All the alternatives you have mentioned starting with the one in post #1 should work and they do work on transformer outputs without problems. The fact that you have distortion which depends on the setting of the control leads me to believe there is something else wrong with your preamp.

Cheers

Ian
 

vmanj

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Oct 3, 2017
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254
Everything turned out to be much easier.
In my E-MU 0404 USB audio interface, the line inputs are non-switchable input Hi-Z sets.
I tried to turn on the preamplifier in the Tascam US-144 mk2 - everything worked perfectly.
Thanks everyone!
 
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