Golden Age Project PRE-73 DLX 1-Channel Vintage Style Microphone Preamplifier with High Pass Filter

Vintage Style Mic Preamp. A Deluxe Version of the Pre-73 Mk2 (A 230V power adaptor is included.)
The PRE-73 DLX is a one-channel vintage style microphone-, line- and instrument preamplifier. The signal path uses only discrete components like resistors, capacitors and transistors. The line and microphone input and the line output are transformer balanced, using three different transformers, each one optimized for its purpose. This is the way audio components were built before integrated circuits became available. The subjective sound quality delivered by vintage equipment is often preferred over the one delivered by modern units, a situation that is even more obvious now when music is recorded with clean-sounding digital audio equipment.

The circuit used in the PRE-73 DLX is similar to the preamp section in the classical 1073 module with a corresponding sound character that is warm, punchy, sweet and musical. These classic characteristics have been heard on countless recordings through the years and it is a versatile sound that works very well on most sound sources and in most genres. The essence of this sound is now available at a surprisingly low cost, making it available to nearly everyone.

Improvements Compared to the PRE73-MKII
• Tantalum capacitors in the signal path
• Selectable 1073-style high pass filter, 50Hz, 80Hz, 160Hz and 300Hz
• Output Attenuator -7, -14, -21 and -28 dB (located after the output transformer) allows overdriving the output stage and the output transformer for added character by lowering the output signal to a suitable level
• The circuit board is prepared for Carnhill Mic and Line transformer and high pass inductor
• The Insert jack can be switched in/out from the front panel. An internal jumper can select that the Insert jack always has an output signal
• Switchable 600 ohm Output Termination and Ground Lift on the back panel
• Selectable Active or Passive DI input and selectable input impedance in active mode, Hi Z or 100 kohm, by internal jumpers
• The DI can signal can be selected to pass or bypass the mic input transformer by internal jumpers
• Relays are used to control internal switching for DI input, Phantom power, Mic Low Z, Insert and Phase for shorter circuit board signal paths. The relays are controlled by front panel switches
• Revised gain switch for added headroom
• Circuit board star grounding scheme
• Revised power supply with separate regulators for the audio circuits and relay and LED circuits