Technics RS-7500

preliminary

Hard to believe, but the RS-7500 was the small unit from Technics !
The last pre-production sample had a completely opaque (el)cassette door and minor design differences around the meters.

Given the fate of the EL format, the big deck only saw the light of day as two RS-7900 pre-production prototypes but the RS-7500 nevertheless is bigger and taller than most power amplifiers produced then or since - really.

Albeit bigger, the RS-7500 is not a Sony EL-7 : the latter is all direct-drive while the 7500 is all belt-driven (plenty of them).
Feature-wise, the 7500 is closer to an EL-5 even if it had clunky mechanical transport pads. Tape type detection was however automatic, just like on Sony's small EL-4, and three hard permalloy heads allow monitoring... like an EL-7.

The best formulation (Type 3, Chrome Bioxyde) was... never made available to the public. The three LEDs were colored to match the tape's color codes : blue for Type I, red for Type II and orange for the unseen Type III.

Six-transisor constant-voltage power supply, one FG DC Servo motors, low-noise FET amp with metal-film caps, high input imedance amp for the mix/line mixing amp, electronic on/of switching and photo-electric end-of-tape detection.

Sound-wise, as all other EL recorders, quite impressive and very rarely in need of using noise reduction : ELCASET was an excellent format. It just came too late by two years.
Technics in the US still advertised for it in early 1979 but that was the last of it.



This page will be updated later on with the japanese dedicated catalog which cost me a sizeable amount of cash - it really is extra-rare.

A (short) review of Technics' big 1976/77 high-end push at gramophone.net.