26 November 2018

SONY TC-R7-2 (1977) - To be heard to be believed

reel to reel



Sony's hi-fi components line has to be heard to be believed. With the lowest wow and flutter of any deck Sony ever built, a duo of tape recorders were introduced in 1977. These were the Japanese market SONY TC-R6 and SONY TC-R7-2. The same models were available worldwide as SONY TC-765 and SONY TC-766-2. They both share the same construction but while the R6 is a 4 Track Stereo Recorder running at 9.5 and 19 cm/s the R7-2 is a 2 Track Stereo Recorder running at 19 and 38 cm/s with an additional 4 Track head for playback. The SONY TC-R7-2 achieves an incredible wow and flutter of 0.018% (WRMS) at 38 cm/s and 0.04% (WRMS) at 19 cm/s. This is achieved via a Closed Loop Dual Capstan Tape Drive System. One capstan extends from the motor shaft itself, eliminating intervening gears that can hamper speed accuracy. The other tape drive capstan connects through an extremely steady belt-drive inertia wheel. For a "mirror image" of the original signal, Sony's exclusive Phase Compensator Circuit comes closest achieving this by rectifying phase distortion and producing sound qualitty virtually identical to the original source. 

Illuminated, calibrated and ultra-clear for best monitoring possible, Sony's Professional Studio Standard VU meters are identical in size, shape, color and sensitivity to those on professional consoles. Because of Sony's outstanding Ferrite & Ferrite Heads, plus the remarkably precise fabrication and alignment of the head gap, recordings retain exact positioning of signal throughout the stereo field. The "location" of individual sounds won't wander. There's no annoying phase shift. More professional features include direct-coupled playback FET amplifier, flashing Standby Signal, Punch-in Record and solenoid-operated Logic-Controlled Transport Functions to let you move instantly to and from any mode without stopping. Standard equipment: RM-30 full-function remote control unit with record mute and hinged head cover.

reel to reel

reel to reel

reel to reel

reel to reel


19 November 2018

Technics RS-M95 - Professional Series (1979)

cassette deck

The RS-M95 was the last incarnation of the very successful series introduced with the RS-M85. Technics has designed the RS-M95 with three heads, each designed for its special role in the recording and playback process. For low distortion. the recordinq head gap is set at a precise 5 micron. The playback head's tiny 1 micron gap provides a new level of high range frequency response. Both heads feature a special version of Technics' own HPF material for the gap and core to raise the saturation flux density to the heights needed for high input metal tape recording. To bring out its full potential, metal tape needs about twice the recording bias current of normal tape, plus specialized (recording) equalization to deal with its high frequency characteristics. Therefore, the M95 not only has the conventional three positions on its tape selector, it also features a metal position especially for the new breed of metal particle tapes. On top of this, you get added flexibility by using independent fine bias adjustment knobs for each tape type. These can be set for  +/-20% of the conventional bias current to deal with each and every brand of tape. And the built-in oscillator provides 400Hz/8kHz test-tone signals for use in this calibration. 

Wow and flutter were the lowest ever in a Technics cassette deck thanks to the combination of the proven quartz phase-locked direct-drive capstan motor and a computer controlled tape tension control system in the reel drive section. As the major determinant of tape travel accuracy, the capstan motor features highly stable, constant rotation. The servo system is based on a quartz oscillator reference frequency and is phase-locked with Technics' famous planar-opposed DC brushless, coreless, slotless, direcl-drive motor. To bring out the full potential of the quartz DD drive system and ensure optimum head contact with the 3-head configuration, Technics has provided the M95 with a remarkable tape tension control circuit. Based on detection of take-up reel rotations and calculation of the diameter of the tape wound on the reel, a microprocessor regulate the reel motor torque to maintain constant tape tension. Extremely high accuracy is achieved because reel rotation detection itself is carried out by counting the number of reel table pulses within a reference period set by the quartz oscillator frequency. A tension arm on the supply reel side provides the back tension needed. 

Technics has led the field in employing new FL meters as a more accurate and convenient alternative to needle type meters. Now in the M95 a newly developed professional quality FL meter with an extended indication range of -42dB ~ +8dB (30 segments: -6dB ~ +4dB are in 1dB steps; each of the other segments cover 2dB steps; for easier legibility, 0dB and above is a brighter red) is used. Timer start selector, record muting switch and feather-touch controls adds to the list of functions of this Professional Series deck while EIA rack mounting makes this deck a perfect match for the Professional 10000 Series audio components. 

cassette deck

cassette deck

cassette deck

cassette deck

cassette deck

10000 series

13 November 2018

FERROGRAPH Logic 7 (1974) - British High Quality

reel to reel

Logic 7 recorders from Ferrograph were high quality British machines. Models available were the 7602H 1/2 track stereo recorder, 7604H 1/4 track stereo recorder, 7622H 1/2 track with power amplifiers & loudspeakers and 7624H 1/4 track with power amplifiers & loudspeakers. The A suffix models were for 117V, 60Hz machines while the D suffix models were equipped with Dolby-B noise reduction. Recording quality was excellent using three heads and separate amplifiers for record and play. Two large, illuminated VU meters read recording or replay levels or the bias (which is adjustable for each channel). Multiple recordings can be made in mono using the track transfer facilities and eletronic echo can be added to mono or stereo recordings. Input mixing allows microphone and line signals to be set individually for each channel and faded up or down with a Master control.

reel to reel

reel to reel

reel to reel

reel to reel




05 November 2018

TANDBERG TD 20A (1977) - 4 Motor Reel to Reel Recorder

reel to reel


The TD 20 A was Tandberg's first open-reel recorder to incorporate the ACTILINEAR process. ACTILINEAR recording include a dramatic increase (20 dB) in the signal handling capacity of the record electronics making them essentially immune to slew-rate limiting and transient intermodulation distortion (TIM). This means better transient response and lower distortion level. Front-panel bias adjustment controls have been included to facilitate optimum performance with any known or prospective tape. Four separate record-level controls, plus a master record control, permit full mic/line and line/line mixing, and a switchable 25 dB microphone attenuator is provided to prevent possible overload when using high output specialty microphones. 

The TD 20 A transport contains four motors rather than three. The capstan is driven by a brushless synchronous motor, and uses a belt drive and heavy flywheel to eliminate vibrations from being transferred from the motor to the capstan. The two reel motors are directly coupled to the reel turntables, and are controlled by a "PROM" (program read only memory) with a trial output to provide constant tape tension. The fourth motor is used to operate the pinch roller and tape gate, achieving smooth, noisless control impossible with the conventional solenoid activated system. A 5 mm thick aluminium baseplate rolled under 40 tons of pressure in a unique "honeycomb" design eliminates stress and greatly increases strenght. Tandberg's full-logic button control permits you to go from rewind into playback with complete safety, and allows the inclusion of "step-stop" editing with full monitoring capability. An optional infra-red remote control is also available. It was sold in two versions: 4 tracks and 2 tracks.


reel to reel

reel to reel

reel to reel

reel to reel