Installation, Audio connections – Drawmer 1960 Mic-Pre/Tube Compressor User Manual

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The 1960 is designed for standard 19" rack mounting and occupies 2U of rack space.
Avoid mounting the unit directly above power amplifiers or power supplies that radiate
significant amounts of heat and always connect the mains earth to the unit. Fibre or
plastic washers may be used to prevent the front panel becoming marked by the
mounting bolts. Because the tube circuitry generates more heat than an equivalent
solid-state design, it is advisable to leave space above the unit to allow the heat to


The inputs and outputs are electronically balanced on conventionally wired XLRs (pin
1 screen, pin 2 hot, pin 3 cold and XLR shell is connected to chassis). The 1960 fully
conforms to the EMC standards, if the unit is used where it maybe exposed to high
levels of disturbance such as found close to a TV or radio transmitter we suggest that
the screen of the signal cable is connected to the chassis connection on the XLR type
connector. The operating level is nominally +4dBu.

If earth loop problems are encountered, do not disconnect the mains earth but instead,
try disconnecting the signal screen on one end of the cables connecting the outputs of
the 1960 to the patchbay. Balanced operation is recommended.

The side-chain access point and the two different level insert points are unbalanced.
The side chain feature on the 1960 is part of the compressor feedback stage and would
normally be connected to a normalised or semi-normalised pair of patchbay contacts.
This would allow the user to insert additional EQ for some de-essing, or frequency
conscious compression. The intended use of the audio insert jacks would be to patch
in EQ (eg 1961), reverb or similar processing. Connection is via stereo ¼" jacks, the
wiring convention being: ring is signal send, tip is signal return and sleeve ground.