Terry Triple Discrete Mic/Line Preamp - 3 Pre

A new tri-fidelity microphone and line preamp using classic transistors and parts.

Based on the experiences with console channels providing a more finished sound by going through more discrete amplifier stages - but without too many transformers - the Triple Discrete Preamp is an exercise of using the discrete opamp of the CEQ *twice*, along with an additional switchable interstage discrete opamp and transformerless input and outputs for a big & immediate, yet delicate and large sound with many subtle ways to focus in to the sound and presentation of your source.

LINE input mode: Without engaging the MIC amp or the INTERSTAGE amp, you go through one CEQ opamp as a LINE input with 0-12db+ of trim. Use this as an extra line amp during any recording or mixing, or even on a master print.

INTERSTAGE: You can engage the INTERSTAGE amplifier at any time to use it's harmonic content for either MIC or LINE signals with an extra adjustable 0-16db+ of gain.

MIC mode: The MIC amp is a feedback adjustable amplifier from +36 to +48db of gain. Subtle changes of the feedback/gain control give a focusing effect to the source.

PAD: For 'hot' microphones that normally overload a MIC amp, simply use the INTERSTAGE amp as well as the main LINE amp together, and disengage the MIC mode, for +28db of gain and a better noise floor than traditional -20db passive pads.

Illuminated switches for +48 (phantom power) and Phase/Polarity flip are also present.

Vintage Philips 'Tropical Fish' capacitors were sourced are used in this first build.

Adding the three stages together gives a total of +78 db of possible gain and drive abilities between the amplifier stages.

Note: Due to the nature of using classic transistors, there is a recommendation of only +64db of gain before the noise floor exceeds that of analog tape for very quiet microphones. The extra gain total is provided to be used creatively. If you don't mind a little bit of tape hiss levels, then more gain is here for you. The amount is very on par with classic 1960 and early 1970's racked preamps and desk channels of the era.