3-Way Preamp Bias Switch: Is it worth It?

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FourT6and2
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3-Way Preamp Bias Switch: Is it worth It?

Post by FourT6and2 » Sat May 27, 2017 7:34 pm

I'm thinking about adding a 3-way switch to the cathode of either V1 or V2 of an amp, so I can select between 0.68uF cathode cap and 820R, 1k5, and 2k7 resistors. I'm sure some of you have tried this? Is it worth the effort or do you find you typically don't use the switch and always keep it in one position? This amp is a high-gain Jose-master style. I suppose I could just clip the resistors in parallel with some alligator leads to test it out with each instead of installing a switch.

Who's done it? What'd you think?

I've played around with an RC calculator to see the frequency roll-offs of each resistor, but there's only so much you can see in the math. I gotta actually hear the difference to know.

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