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Old 24th Dec 2012, 6:52 am   #88
GP49000
Hexode
 
Join Date: Mar 2012
Location: Sonoma County, California, USA.
Posts: 405
Default Re: Garrard record player deck identification.

The Reverse Unimechs

One of the "traditional" features separating "Automatic Turntables" from ordinary record changers was the lack of an overarm to stabilize the stack of records on the multiple-play spindle. Eliminating the overarm made it easier to play single records using the short, manual play spindle, and cleaned up the appearance of the record playing unit. Different manufacturers had different means of accomplishing this. Most used a tripoise spindle that balanced the stack of records on three retractible "arms." Garrard first used their traditional pusher platform, then tried a tripoise spindle in the Lab 80, and finally settled on a conventional pusher spindle with a record support platform in the right rear of the unit, in the SL95 and later "automatic turntable" models.

The SL95 and its offspring, and later the models based on the GT-series modular mechanism, were purposely designed with a record support platform. But the Unimech models were not. Garrard wished to attach some of the "Automatic Turntable" cachet to the decidedly ordinary record changers in the Unimech line by incorporating the record support platform and getting rid of the overarm. This required that the action of the record changing spindle be altered. The standard Unimech design, like the Autoslims, pushed records off their spindles toward the right rear; but with a record support platform, they would have to push the records toward the left front instead, so they would fall off the record support platform. From the basic Unimech subchassis, linkages were modified to accomplish this, and the spindle itself was rotated by 180°, exactly reversed; hence the designation "Reverse Unimech" for models so equipped. A slightly inclined spindle was another modification.

The 6-400 was the basic Reverse Unimech model. It was similar to the 6-300 except for lacking an overarm and having a record support platform instead, with the reversed linkages and spindle. It also had a different antiskating device, adjusted by a lever on a calibrated scale instead of a knob. The 6-400 was built with both two-pole and four-pole motors. Trim items such as the platter mat could vary.

The Model 62 was primarily intended for the USA market. It had the more advanced tonearm of the 440 series, with non-adjustable counterweight, a knob and a graduated scale for easy adjustment of tracking weight, and the removable C4 cartridge slide. It did NOT have the 440's dual-calibrated antiskate adjustment, but rather the 6-400's single calibration. Early on it was finished in white to match the Zero 100, Zero 92 and Model 82. Later, it was made in black, as the white scheme was abandoned through the entire line.

The Model 70...not to be confused with the earlier A70 and 70 Mk II...had a fully counterbalanced tonearm with adjustable counterweight, and a downward pulling spring for tracking weight. Its adjustment was by a knob with a tracking weight scale calibrated in grams. It had needle pivots for vertical tonearm movement, and the removable C4 cartridge clip. Antiskating adjustment was by a lever with a single calibration, like the Model 62 and 6-400. It was built only with the Synchro-Lab induction/synchronous motor and had an additional, fixed counterbalance underneath the unit plate, to make its tonearm balance insensitive to tilting of the unit. To give it the "Zero 100" look, it was built with a transparent plastic housing around the pickup arm's gimbal, and like the Model 62, it was first produced in white, for a "family resemblance" to the Zero 100, and later in black.

The Model 770 was a slightly modified Model 70. It added a dual calibration to its antiskate adjustment, for spherical and elliptical styli; but omitted the auxiliary tonearm counterbalancing under the unit plate.

In America, the Reverse Unimechs were touted as advances and improvements over predecessor models. The Model 62 was intended to replace the SL55B, while claimed to be so far superior that it defied meaningful comparison. The Model 70 reached even higher. Although it was nominally the successor to the SL65B, it was claimed to be every bit the equal in appearance, features and performance to the more expensive SL72B. However, the balky Unimech operating controls and the horizontal tonearm pivotry virtually unchanged from the CC10 minichanger made such claims dubious. Sales of the Models 62 and 70 in the USA were poor. Elsewhere, the 6-400 and 770 did no better.

Photos:

6-400
Model 62, white, in USA catalog illustration
Model 62, white
Unimech spindle
Reverse Unimech spindle (both viewed approximately as from tonearm head)
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Last edited by GP49000; 24th Dec 2012 at 7:16 am.
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