The Avalon VT-737SP features a combination of TUBE preamplifiers, opto-compressor, sweep equalizer, output level and VU metering in a 2U space.

• Circuit topology
  Four dual triode vacuum tubes (Sovtek 6922), high-voltage discrete Class A
• Gain Range
  Microphone: Transformer balanced 850/2500 ohm, 0dB to +58dB
  Instrument: Unbalanced 1 meg ohm, 0dB to+30dB Line: Balanced Class A 20k ohms, -27dB to 28dB
• Maximum input level and connector types
  Microphone26dB@25Hz, +30dB@1kHz balanced XLR Instrument+30dB unbalanced front panel jack socket
  Line +36dB balanced XLR
• Maximum output level
  +30dB balanced 600 ohms, DC coupled, discrete Class A
• Output type and gain
  XLR connector, output trim gain -45dB to20dB
• Noise 20kHz unweighted
  -92dB
• Noise microphone EIN
  -116dB, 22Hz to 22kHz unweighted
• Distortion THD, IMD
  0.5%
• Frequency response -/2.5dB
  10Hz to 120kHz input filter included
• Frequency response -3dB
  1Hz to 200kHz line in-out
• VU meter and gain reduction
  High quality illuminated OVU =+4dB and gain reduction to -20dB
• High cut filter
  Variable 6dB per octave 30Hz to 140Hz
• Compressor type
  Optical passive attenuator incorporating twin vacuum tubes and stereo link
• Threshold - Ratio
  Threshold variable -30dB to +20dB, ratio-compression variable 1:1 to 20:1
• Attack - Release
  Attack variable 2mS to 200mS, release variable 100mS to 5 seconds
• Equalizer type
  Discrete Class A, variable active and switched passive design
• Frequency bands (4)
  Treble - switched 10kHz, 15kHz, 20kHz, 32kHz, +/- 20dB range, shelf High mid - variable 200Hz to 2k8Hz and 2kHz to 28kHz, +/- 16dB range, hi-lo Q Low mid - variable 30Hz to 450Hz and 300Hz to 4k5Hz, +/- 16dB range, hi-lo Q Bass - switched 15Hz, 30Hz, 60Hz, 150Hz, +/- 24dB range, shelf
• AC power
  Internal toroidal 100v to 240v, 50-60Hz selectable, 75 watts maximum
• Dimensions
  19 x 12 x 3.5 in (482 x 305 x 89mm)
• Weight
  22lbs (10kg)
• Dimensions-shipping carton
  21 x 18 x 8 in (533 x 457 x 203mm)
• Weight-packed
  26lbs (11.8kg)

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