The Psidex Audio Laboratory PGP- 1A is a vacuum tube based microphone pre-amp and

program line amplifier designed to provide solid, robust audio from any low impedance

microphone ranging from low output ribbon to high output condenser.

A 30 dB input attenuator is provided to allow using the unit as a bridging line amplifier,

general purpose gain block or mixing amplifier.





Gain switch sets gain for 30, 40, 50 and 60 dB gain.

Output level control allows setting output from zero to +6 dB above switch setting.

A 30 dB input pad permits use with high level inputs and increases input Z.

Output phase reversal switch.

Output termination switch.

Standard XLR 3 pin input- output connectors.

Additional front mounted input jack for extra versatility.

VU meter switch for +4 dB, +10 dB calibration or off.

Mic phantom power switch interlocked with input pad switch.

Very large input and output transformers for clean low end.

Regulated HV and LV power supplies.

High quality polypropylene capacitors.

Mil spec Teflon wiring.

Tubes (2) recessed, replaceable from rear.









Gain 36,46, 56, 66 Db maximum


Distortion 0.008% @ +10 dBm, terminated at 600 W


Noise, -87 dB below +10 output for 30 dB gain

Wideband -87 dB below +10 output for 40 dB gain

5 Hz-30 kHz -80 dB below +10 output for 50 dB gain

-70 dB below +10 output for 60 dB gain

Noise, -92 dB below +10 output for 30 dB gain

A Weighted -92 dB below +10 output for 40 dB gain

-90 dB below +10 output for 50 dB gain

-80 dB below +10 output for 60 dB gain


Frequency Response 10 Hz to 45 kHz +/- 1 dB


Input- Output <13 deg. lag @ 20 kHz

Phase Shift


Maximum Output +26 dBm terminated 600W



Input Impedance 250W balanced, input pad OUT


Input Impedance 10kW balanced, input pad IN


Output Impedance 600W nominal


Phantom Mic. Power +48 volts via 2x 6.8k


Tubes 12AX7 (1), 6414 (1)




Mains Supply 108-130 or 220- 250 volts Ac, 50/60 Hz.

Mains Selection Internal Jumpers.

Ac Power, V.A 17.3

Power Inlet Standard EIA 3 wire.

Physical Size 2U EIA panel, 3.5 x 19 inches.

Depth 9.5 inches.

Weight 8.5 pounds.





The PGP-1A is sold with a one year warranty against all defects. Vacuum tubes warranted for 45 days.

Replacement or repair at the option of PSIDEX

                         Design and Product specifications may change without notice to maintain quality and performance.


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