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musical instrument details

Rare RCA Pre-Amp Tube amplifier 50s vintage would suit Ribbon microphone

Estimated price for orientation: 1 300 $

Category: Preamps and Channel Strips
Class:











Description
Number of Channels: 4 Features: Modular, Rack-Mountable


These Preamps have been taken from a 1950's multitrack track tape recorder (LM99) which formed part of a Sound and Film edit suit. They have been modified slightly at various points between then and now (with various notes pencilled in the original instruction manual), and all units have new smoothing caps.
All inputs and outputs are balanced TRS jacks, on the original patch bay. All of the units plug into the 19" rack mount box, which houses the power supply and the inputs / outputs. The Power supply is not original. 
LMI-79 - pre amplifier 
200 ohm Parmeko input transformer Three 12au7 valves. Pushpull output into 600 ohms.
 I have the original schematic and instruction manual for this unit. Gain is adjusted with a screwdriver through the front panel
LLMI-7xx  Isolation Amplifier Serial number R-635
Two Chanel Class A preamp.
 One 12au7 per Chanel, 600 ohm Parmeko input and output transformers with gain control's mounted on the top of the unit (see photos)LMI-76 "Recording Amplifier" serial number R-662
200 ohm Parmeko input transformer 
Two 12au7 valves. Pushpull output into 600 ohms.
 I have the original schematic and instruction manual for this unit. Gain is adjusted with a screwdriver through the front panelAll the units work, and have a low noise floor but as I do not have any high spec microphones to fully test them I would suggest they would need to be properly serviced before working at their absolute best.  
All the Units are clean but have clearly been kept in damp conditions in the past so have some light corrosion and scratchy pots. The meter on the front panel is not connected.Any Questions please get in touch.Postage is Via FedEx and free to mainland uk, excluding highlands and islands. Please ask for a quote for any other destination.