I/70 Integrated Amplifier By Audio Research

The I/70 integrated amplifier delivers the warmth and musicality of tube audio in a refined, space-saving design that combines high-performance preamplifier and amplifier technology into one elegant component.

Its sophisticated styling draws inspiration from flagship reference models, featuring anodized aluminum accents, precision-machined detailing, and a fully enclosed transformer section for a modern, premium appearance. Available in black or silver finishes, the design blends classic tube aesthetics with contemporary craftsmanship.

Inside, the I/70 incorporates high-quality output transformers and four KT120 output tubes to produce 70 watts per channel of powerful, dynamic sound. The result is impressive control, clarity, and resolution with the rich tonal character tube enthusiasts value.

Automatic biasing helps maintain consistent performance without manual adjustment, making everyday operation simple and reliable.

Designed to pair confidently with a wide range of loudspeakers, including floor-standing models, the I/70 offers a spacious, authoritative presentation with exceptional musical engagement.

The integrated design includes independent tube preamplifier and power amplifier sections, along with stereo preamplifier outputs for added system flexibility, including connection to powered subwoofers.

A precision 75-step volume control allows fine adjustment across varying recording levels, while the dedicated headphone output—driven directly by the KT120 tubes—delivers an immersive personal listening experience for high-end headphones.

Digital connectivity is equally impressive, with a high-resolution DAC supporting USB, Optical, Coaxial, and Bluetooth inputs. Advanced upsampling technology enhances detail, transparency, and tonal purity for exceptional digital playback.

Additional connectivity includes three single-ended inputs and one balanced XLR input. An optional phono stage supports both moving magnet and moving coil cartridges, with adjustable gain and loading settings accessible via remote control.

Combining power, finesse, and versatility, the I/70 offers a premium tube audio experience with the performance and musicality typically associated with far larger separate components.

Enjoy The Music
“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.”

https://www.enjoythemusic.com/magazine/equipment/0326/Audio_Research_I70_DAC_MM_MC_Phono_Integrated_Vacuum_Tube_Amplifier_Review.htm

Architeg Prints
“Whether you’re a devoted tube enthusiast or a curious new listener, the Audio Research I/70 integrated amplifier deserves a listen. It proves that even a brand synonymous with tubes can successfully embrace solid-state design without losing the essence that made it famous.”

https://www.architeg-prints.com/blog/audio-research-i70-integrated-amplifier-review-a-solid-state-classic?srsltid=AfmBOoquOFaHEW4XrRxrqFIu4FOiyScstCFxIXF5RvZlHct_VPPMTER-

• 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 “conditioning” 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