Audio Research i/70 Integrated Vacuum Tube Amplifier

$21,100.00

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Colour: Black

Black

Silver

Extra input: None

None

DAC Card

Phono Card

Product variants

The 1/70 brings the joy of tube audio playback to those seeking an elevated level of musical performance, combining Audio Research separates in a single elegant, compact package.

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Specifications

Power Output: 70 watts continuous from 20Hz to 20kHz. 1kHz total harmonic distortion typically 1% per channel, below 0.1% at 1 watt

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)

Output Taps: 8 ohms, 4 ohms

Power Requirements: 105-130VAC 60Hz (210-250VAC 50Hz) 252 watts at rated output.

Tubes 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

Sit down, get comfortable, dim the lights, open your ears, and… enjoy the music.

Enjoy the Music

Pure Valve Performance

The I/70's visual design takes cues directly from the REF330M. Black or silver anodized top and bottom plinths mate with a fully enclosed transformer array topped with machined aluminum, mesh, and badging inspired by the 330M. A full mesh wrap around the bottom chassis and an additional bottom plinth complete the 1/70's upscale look.

The beauty continues inside. The same output transformer used in the famed Reference 75 amplifier, combined with four KT120 output tubes, produce 70 watts per channel. There is dynamic swing, a sense of command, control and resolution that were previously unimagined in this category.

Auto-bias ensures maximum performance daily with no extra effort from the listener.

The I/70 sounds like a big amp. Go ahead, use it with your favorite floor-standing speakers and hear what a great tube system can bring to your music.

Experience the Magic of Valves

The 1/70 integrated amp has independent tube pre-amplifier and tube amplifier sections, providing flexibility with a set of stereo pre-amplifier outputs. While we suspect very few listeners will pair it with an external power amp, many will need this feature to feed powered subwoofers that offer only low-level inputs.

The active pre-amplifier section offers a wide range of gain settings, now with a 75-step volume control. This is especially helpful with recordings that are cut at a low gain setting for wide dynamic range.
The headphone output is driven by the KT120 output tubes. It was designed for high quality headphones, able to provide the best possible personal listening experience.

Optional DAC Module

The DAC card's AKM Velvet Sound DAC chip provides high resolution formats over USB, Optical, Coax, and Bluetooth. All are upsampled. The result is fine resolution, great transparency, and tonal purity that is rarely heard outside of the finest separate DACs.
There are three sets of single-ended inputs and one set of Balanced
XLR inputs. The optional phono card has both MC and MM gain settings, controlled via the I/70 remote. MC loading is also adjustable, from 50 to 1k ohms.
The I/70 delivers the punch, detail and musicality that evoke the performance of Audio Research's larger separates. It continues the Audio Research heritage, built by hand in their Minnesota facility, twice tested, and individually auditioned in our reference system.

Audio Search's I/70 stereo unit is built like a tank and should last for decades. For some lucky soul, this vacuum tube unit with Hi-Res DAC and high-end audio MM/MC phono stage option will be a time machine that takes you back to memories of both today and long ago. Sit down, get comfortable, dim the lights, open your ears, and… enjoy the music.