PO Box 339, Gillette, NJ 07933
TEL: (201) 728-8490
AM670 Condensed Operating Instructions
The INPUT controls are continuously adjustable from -15dB
to +15dB. Unity gain is at the center postion.
The THRESHOLD controls are continuously adjustable from
0 (off) to 10 (maximum limiting).
Eight position rotary switch for selecting one of eight preset
combinations of attack and release time. Time constants get
progressively slower as the preset number increases. Presets
5 and 6 are multi-slope (auto).
Three position rotary switch for selecting Input level (IN),
Gain Reduction (ZERO) or Output level (OUT).
Screwdriver-adjustable trim controls for setting the meter to zero
when indicating Gain Reduction.
Engaging the IN pushbutton puts the AM670 into the signal path,
and the meter illumation brightens. When the switch is out, the
unit is in hard bypass. Hard bypass is the default mode when ac
power is turned off.
Switch for selecting one of three modes of operation.
LEFT/RIGHT indicates dual mono (split). STEREO links the
sidechains of the left and right channels. LAT/VERT encodes and
decodes the left and right channels for Mid-Sides (M-S) Limiting.
AC power switch. The meters are dimly lit when ac power is
applied, but channels are in bypass. The neon lamp indicates
when the unit is on.
The XLR input and outputs are active-balanced with pin 2 hot.
To operate the outputs unbalanced, pin 3 MUST be grounded.
Standard 3 pin IEC ac inlet. The ac line voltage for the AM670
is internally set at the factory. It is indicated on the rear panel.
• Classic Fairchild Variable-Mu compression profile and vintage tone
• Six 670 time constants plus two vocal-friendly variations
• New and unique GRC (Gain Control Computer) technology
• Three modes of compression: Dual Mono, Stereo, and Mid-Sides (M-S)
• All analog signal path wi