The circuit below started off life as a pretty standard diamond buffer, and I'm planning next on building this modified version:   It sims out nicely in LTSpice: low distortion, good PSRR, and (as far as I can tell) reasonable bias stability towards voltage and temperature changes.   I'm...

Original   The LTSpice results match my measurements on a similar amplifier, so I am confident that the distortion predicted for the Szekeres circuit is realistic.   So here you go. The not-quite-an-answer to the question probably few people other than myself was interested in: "Is the...

Two boards are required for stereo. I have four pairs available to anyone willing to be a beta-tester. Cost is $20 shipped (this is at-cost pricing, I'm just interested in having a few more people try this out.) PM if interested.   The Sapphire amplifier is a fairly standard op amp + diamond...

  Hard to figure out which is the right forum, here or computer audio. Anyhow, if anyone was wondering (as I was) what the insides of the little beastie look like, wonder no longer:     Revealed: a pretty dense layout, most SMT, with a daughterboard for the volume control and...

Please Download the schematic. I've got as far as finishing the circuit values and designing the board, but I'm sure there are still a few things I've missed that should best be sorted out before getting a prototype up and running. The circuit is designed to run off a 100k volume pot, and...

After 12 years on Geocities, RJM Audio now has it's own domain: phonoclone.com. The headphone amplifier projects can be found at the following URLs: Twilight hybrid headphone amplifier phonoclone.com/diy_twi.html Szekeres VE headphone amplifier phonoclone.com/diy_sze.html...

This project started some while ago, but with the recent addition of a small, single-sided circuit board I thought it might be worth posting to the head-fi forum. The Xreg is a voltage stabilizer for removing hum and noise from the power supply. It requires one dual opamp (e.g. NE5532), two...

6CG7 + several 2SK213s, mu-follower topology with additional MOSFETs as line smoothers. It took me two years to get around and finish the thing, and the concept - a single tube headphone amp - has been kicking around my head for more than a decade I guess. It ended up a bit bigger than I...