VAC’s revolutionary iQ System keeps each output tube’s operating point perfectly steady at all times. This breakthrough circuitry provides a solid and stable foundation to the music.

Jim Hannon, The Absolute Sound

The new VAC Sigma 170i is the world’s first integrated amplifier with the patented iQ Continuous Intelligent Automatic Bias System. The iQ System holds the true idle point of the output tubes perfectly steady under all conditions, increasing detail & dynamics, lowering distortion & noise, prolonging tube life, and protecting the amplifier. Integrated amplifiers are a great lifestyle choice, and VAC lets you have all of the benefits of tubes without the worry.  

  • Wattage: 85 watts/channel
  • Power Bandwidth: 13 Hz to 70 kHz
  • Inputs: Four line level inputs plus one Cinema Bypass input; Optional balanced input on Input 4; Optional MM/MC phono on Input 1
  • Outputs: Connections to precisely match loudspeaker loads of 4, 8 and 16 ohms
  • Tubes: 4x KT88, 5x 12AU7A 1x 12AX7A
  • Voltage: May be factory-configured for operation at 100, 120, 220, or 230/240 volts
  • Power Cord: Detachable power cord, standard IEC power receptacle
  • Remote Control: Volume & Mute, included
  • Finish: Hand-rubbed gold-flake gloss black lacquer fascia with chrome knobs standard. Hand-rubbed metallic gloss silver lacquer fascia with chrome knobs special order with additional cost.
  • Warranty: Two years parts and labor, excluding tubes (USA, see manual for full details)
  • Dimensions (H x W x D): 8 x 18 x 17.3 in. (203 x 457 x 440 mm.)
  • Shipping Weight: 71 lbs. (32 kg.)

Phono option:

  • Gain: 37 dB MM, 57 dB MC
  • Frequency Response: RIAA +/‑ 0.2 dB
  • Residual Noise: 3 mV at output (S/N ratio approx. 69 dB)
  • Overload: 117 mV @ 1 kHz = 8 volts RMS output; 460 mV @ 10 kHz
  • Variable loading: Yes for MC
  • Tubes: 2x 12AX7A

*Specifications subject to change without notice.

VAC’s revolutionary iQ System keeps each output tube’s operating point perfectly steady at all times. This breakthrough circuitry provides a solid and stable foundation to the music. It automatically biases each tube, and eliminates tube drift and the deleterious effects of line variations on the sound. A system with four VAC 200iQ amplifiers driving Focal Grand Utopia EMs produced a sound with great imaging, natural timbres, deep bass extension, and startling dynamics.


Pairs well with