This unit is a 4-channel 1RU audio mixer.

Features:

• Live Performance mixers designed to operate in Mono, Stereo, or LCR applications.
• ProSpec-1U4M4S: 4 Channels of Professional Quality Burr-Brown Microphone Pre-Amplifiers and 4 balanced stereo line input channels.
• ProSpec-1U8M: 8 Channels of Professional Quality Burr-Brown Microphone Pre-Amplifiers.
• Balanced Left, Right, and Mono (center) XLR outputs use THAT Corporation Outsmarts devices.
• All front panel switches are internally illuminated.
• Individual Solo switch on each mono and stereo input channel.
• Monitor headphone level control with 1/4” and 1/8” headphone connectors and rear panel APB mixer link connector.
• Each input channel is assignable to Left-Right or Mono (Center) mix bus
• Level and Pan controls on Mono input channels / Level and Balance controls on Stereo input channels.
• Mono input channels have 48-Volt Phantom Power, High Pass Filter, Polarity Reverse and Assignment switches.
• Stereo input channels have Mute, Polarity Reverse, and Assignment switches.
• Individual Left, Right, and Mono (Center) Metering.
• Front panel Left-Right sum switch
• Mono input channel use Neutrik XLR/1/4” combo connectors and TRS insert points
• Stereo input use individual 1/4” balanced left and right input connectors.
• Low phase-shift, wide bandwidth electronic design derived from APB’s Spectra and ProDesk products.

Specifications:

Mono Input Channel
Balanced Mic Input (XLR Input of Combo Connector)

• Mic Gain (Max): 60 dB
• Mic Input Z: 2k O
• Mic EIN: -127 dBu @ 60dB gain, 150 O source
• THD + Noise (Mic input to Main Output): <0.005% @ 15dBu Output
• Bandwidth:
    -  @ 40dB Gain >200kHz (ref to 1kHz) Microphone Input to Main Output
    -  @ 60dB Gain approx 160 kHz (ref 1kHz)
• Phase response: +/-11 degrees, 20Hz to 20kHz (ref 1kHz)
• HPF: 75Hz @-18dB/Octave
• Unity Gain approx 2 o’clock Pot rotation

Balanced Line Input (TRS input of Combo Connector)

• Line Gain (Max): 42 dB
• Line Input Z: >10k O
• THD + Noise (Line input to Main Output): <0.01% @ 15dBu Output
• Bandwidth approx 160kHz (ref to 1kHz) Line Input to Main Output
• Phase Response: +1.5/-17.5 degrees 20Hz to 20kHz (ref 1kHz)
• Unity Gain approx 10 o’clock Pot rotation: 10 dB

Stereo Channel
Balanced Line Input (TRS)

• Max Gain: 20 dB
• Line Input Z: >10k O
• THD + Noise (input to Main Output: <0.005% @ 15dBu Output
• Bandwidth: >200kHz (ref to 1kHz): Input to Main Output
• Phase Response +3/-9 degrees, 20Hz to 20kHz (ref 1kHz)
• HPF: 40Hz @-18dB/Octave
• Unity Gain approx 10 o’clock Pot rotation
• 10 dB Gain at approx 2 o’clock Pot rotation

Outputs

• Balanced XLR using OutSmarts® Driver ICs (also capable of unbalanced operation)
• Max Output Level: +26dBu (into 600 ohms or greater)
• Bal Output Z: 50 O
• Residual Output Noise: < -95 dBu (All channels unassigned and channel sends down, Master at unity (2 o’clock))