• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Thoughts on this "ARC" preamp circuit


2005-08-01 7:12 pm
I bought the following. If there is any interest, I will post my project ideas. I started a lengthy description of my needs and design goals. It seemed a bit much for an introduction. I'll post that tomorrow.

First- most of this project is unnecessary. It is for fun, although I do need the switching capabilities of a preamp without the gain. My amp is a Volksamp Aleph 60, 60-100 watt clone with a sensitivity of 1.25 v to reach full output depending on the speaker load. Everything I have puts out more than 2v. It has a 52k input impedance with the balanced inputs.

Second- I have no issues using a "clone" like this without consent from the manufacturer as there is nothing here that hasn't already come in circuits designed 80 years ago. You shouldn't be able to patent physics (yeah, I'm looking at you, Bose). I'm also not convinced it is actually a clone of anything.

Third- I'm posting because the actual components in the kit look decent and I'm pretty impressed with the quality of the whole thing for the $125 I paid for it.

I'm willing to entertain heavy changes but have no issue with the cathode follower as an output topology. Although that cathode resistance of the 3 parallel resistors seems super low, but more on that later.

Active volume control using feeback?



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