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Rg100es preamp red channel

Started by Kizzlecake, April 13, 2014, 06:07:08 PM

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J M Fahey

VERY good, thanks Roly !!!!  :dbtu:
I use a similar one to get -9V out of +12V to be able to feed bipolar supply preamps in my "Callejero" battery powered street amps.
Why*9*V?
Because in these 555 inverter circuits, you lose a couple volts in each stage (that's why Roly needs 6 double stages instead of 3 or 4) compared to an application specific IC, but since this one is readily available and costs cents, adding a couple extra diodes and caps is nothing compring to paying a few bucks  *+ shipping*  + *the delay*

To get -12V I'd need to add an extra stage plus a voltage regulator (or I'd overshoot) .... not really necessary.
My TL072 based preamps are *happy* with +12/-9V rails.
And anyway I'm a cheap bast....  sorry ..... "minimalist"  :lmao:

Roly

{I'm nothing if not cheap.  ;) }

...and apart from the fact that any electronics parts supplier worthy of the name should have all these bits is stock, cheap, there is an excellent chance that they will still have them in stock, cheap, in one, two, five or more years time when the latest inverter-specific wounderkinde IC is all but forgotten unobtainium - it will still be repairable or repeatable for another build.

The triple-5 has to be one of the best known IC's in the world, so if ever this preamp creation is say sold to somebody who blows it up, any tech will have no trouble understanding and repairing it.  For these reasons it is often better to go for something mainstream that might be a bit less efficient than a "better" off-broadway solution.  Future repairability should always be an important design consideration.
If you say theory and practice don't agree you haven't applied enough theory.

Kizzlecake

always hated unobtainium

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