dbx 676 Tube Microphone Preamplifier / Channel Strip

The 676 puts a 12AU7A/ECC82 vacuum-tube gain stage in front of a full compressor/limiter and a sweepable 3-band EQ, so tracking vocals or instruments through one channel strip covers the whole signal chain. Mic gain runs from off to plus 55 dB and the instrument input to plus 40 dB, with a 20 dB pad, polarity invert, and an 80 Hz high-pass switched in from the front panel.

The compressor offers OverEasy or hard-knee thresholds with a ratio variable from 1:1 to infinity:1, manual or program-dependent auto attack and release, and dbx's PeakPlus limiter sitting after it for a second stage of protection. Mic input is female XLR pin 2 hot, with a matching balanced XLR and 1/4 inch TRS line output, plus insert points on both the preamp and the compressor sidechain. The unit is 3.5 x 19 x 8 inches, 8.1 lbs, on a universal 100-240 VAC supply.

Mic Preamp Connector	Female XLR, pin 2 hot; electronically balanced/unbalanced
Frequency Response (Mic Input)	20 Hz - 50 kHz, +0/-1 dB, 40 dB gain
Gain Range	Minus infinity to +55 dB mic; minus infinity to +40 dB instrument
Compressor Ratio	Variable 1:1 to infinity:1; 60 dB maximum compression
Compressor Threshold	Selectable OverEasy or Hard Knee, -40 dBu to +20 dBu
Limiter	dbx PeakPlus, infinity:1 ratio
EQ	3-band: 100 Hz low shelf, 100 Hz - 8 kHz sweepable mid, 10 kHz high shelf, +/-15 dB
Vacuum Tube	12AU7A / ECC82
Line Outputs	Male XLR and 1/4 in TRS, pin 2 / tip hot
Dimensions / Weight	3.5 in H x 19 in W x 8 in D; 8.1 lbs
Power	100 - 240 VAC, 50/60 Hz, 20 W