Technics RS-1700

The Technics RS-1700 is a flagship auto-reverse reel-to-reel tape deck from the late 1970s, renowned for its Isolated Loop tape path and six-head system enabling seamless playback on both sides of the tape without manual intervention.

The Technics RS-1700 is a highly unique and technically complex reel-to-reel deck because it is the only model in the acclaimed Isolated Loop series to feature auto-reverse capability at all three speeds 3¾, 7½ and 15 ips.

Key Specifications

It supports a 4-track, 2-channel stereo system with auto-reverse, three speeds (3¾, 7½, 15 ips), and up to 10.5-inch reels under NAB equalization. Wow and flutter is 0.018% at 15 ips, frequency response 30Hz–30kHz at 15 ips (±3dB), signal-to-noise ratio 66dB, and total harmonic distortion 0.8%; inputs are 60mV (line)/0.25mV (mic), output 0.775V (line).​

Track Formats

• ½-track (2-track) record & playback

• ¼-track (4-track) playback only

• Auto-reverse is playback only (recording is one direction)

Design Features

Equipped with six Sendust heads (2 erase/record, 2 playback), three direct-drive brushless DC motors (quartz-locked 34mm capstan with dual pinch rollers, tension-controlled reels), photo-electronic auto-stop, logic braking, and low tape tension (~80g) for reduced modulation noise. 

Head Configuration (Key Distinction)

• 6-head system
  Erase
  Record
  Forward playback (½-track)
  Reverse playback (½-track)
  Forward playback (¼-track)
  Reverse playback (¼-track)

This head arrangement allows auto-reverse playback for both 2-track and 4-track tapes.

Recording & Calibration Features

• Front-panel bias adjustment

• Record level calibration

• Playback EQ selection
  NAB / IEC (region-dependent)

• Built-in test oscillator
  1 kHz and 10 kHz tones

• Source / tape monitoring

Recording functions mirror the RS-1500.

Inputs & Outputs

• Unbalanced RCA line inputs and outputs

• Microphone inputs (market-dependent)

• Remote control capability

• No factory balanced XLR I/O (unlike RS-1520)

Auto-Reverse System

A defining feature of the RS-1700:

• Auto-reverse playback

• No tape flipping required

• Maintains azimuth accuracy via dedicated reverse heads

• Particularly useful for:
  Long unattended playback
  Background listening
  Archival auditioning

Recording is single-direction only

Dimensions measure 456 x 446 x 258 mm, with a weight of 25.7 kg for stability.​

Reputation & Legacy

• One of the most complex Technics open-reel machines

• Praised for:
  Exceptional speed stability
  Gentle tape handling
  Reliable auto-reverse design

• Considered the best auto-reverse open-reel deck ever made by many enthusiasts

Collectability & Current Status

• Highly collectible, especially in fully functional auto-reverse condition

• More complex mechanically than RS-1500 → requires careful servicing

• Desirable for:
  Large tape libraries
  Long-form playback
  Audiophile systems needing convenience