Audio Research I/70 Integrated Amplifier

The I/70 integrated amplifier combines Audio Research tube preamp and power amp technology into a compact, elegant design inspired by the flagship REF330M. Using four KT120 tubes and the Reference 75 output transformer it delivers 70 watts per channel with powerful dynamics, detail and control. Features include auto-bias, a 75-step volume control, balanced and single-ended inputs, headphone output driven by the output tubes and optional DAC and phono modules. The DAC supports USB, optical, coaxial and Bluetooth inputs with high-resolution upsampling. Hand-built and individually auditioned in Minnesota the I/70 offers high-end tube performance in a versatile all-in-one package.

Technical Specifications:

Power Output: 70 watts continuous from 20Hz to 20kHz. 1kHz total harmonic distortion typically 1% per channel, below 0.1% at 1 watt (Note that actual power output is dependent upon both line voltage and “condition” i.e.: if power line has high distortion, maximum power will be affected adversely, although from a listening standpoint this is not critical).

Power Bandwidth: (-3dB points) 10Hz to 22kHz

Frequency Response: (-3dB points at 1 watt) 7Hz to 30kHz

Input Sensitivity: 1.25V RMS for rated output

Input Impedance: 100K ohms Balanced, 48K ohms Single Ended

Output Polarity: Non-inverting. Balanced input pin 2+ (IEC-268)

Input Impedance: 100K ohms Balanced, 50K ohms SE ; 8 Inputs – 4 balanced, 4 single-ended

Output Taps: 8 ohms, 4 ohms

Power Requirements: 105-130VAC 60Hz (210-250VAC 50Hz) ; 420 watts at rated output, 220 watts at “idle.”

Tube Required: 2 matched pair KT120; 3-6922 (1 input, 2 driver)

Dimensions:

Width: 16.5” (42 cm)

Height: 8.25” (21 cm)

Depth: 13.5” (34 cm)

Weight: 55 lbs (25 kg); 66 lbs (30 kg) shipping weight