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The X-12 preamp kits are now on sale.

I updated the X-12 PDF guide and explained more about the option of using PDIP8 chips and DOA chips.

The key is using MillMax socket pins on the board. This will allow you to quickly remove the PDIP8 chips, insert your DOA chips and do some listening tests. The DOA chip sits well above the IC sockets. You'd have to remove the PDIP chip though if you want to use DOAs.

Here's the latest photo of the X-12 preamp using an API 2520 clone Discrete Op Amp.

This preamp was inspired by A certain Preamp Indeed!

But no, it's not a clone. Rather, I'd like to call it my FiveFish version

It uses input transformers with high-nickel and mumetal shielding, monolithic opamps and also has the option to use 990/992/2520 discrete opamps, null offset, output transformers, on-board voltage regulators, Relay-controlled -20dB Pads and Polarity Reverse, Soft-start phantom power, LED-lighted push button swithes, Grayhill selector switch, Bourns pot.

It uses a very very low distortion opamp chip for amplification, coupled to a high current, high-slew rate (2000V/us) video buffer driver subjecting that output transformer into submission.

The sound is huge and beefy... it will fight back when pushed hard, and slap you up and down silly to let you know who's boss... kinda like a rock n roll club bouncer.

(VU meter not shown in above photo, 5-LED VU Metering included in kit.)