View Single Post
Old 9th Nov 2012, 9:13 am   #49
GP49000
Hexode
 
Join Date: Mar 2012
Location: Sonoma County, California, USA.
Posts: 405
Default Re: Garrard record player deck identification.

The "Large Chassis B" Garrards

The new "large chassis" introduced in 1968...the SL95, SL75 and AP75...had its problems, and this all came at a particularly inopportune time for Garrard, as its major competitors in automatic turntables, Dual and Miracord, were refining and improving their products, while at the same time the large Garrards did not seem to feel as solid as did their predecessors, particularly the Lab 80.

Among the problems that arose (a lot of this is from my own memory, as this all happened when I became keenly interested in hi-fi):

The rotary controls for automatic play and manual play/cueing tended to shake the unit too much when the user turned them, particularly to operate the cueing device or automatically reject a record. The Lab 80's tab controls were gentler to operate, Dual's function controls were feather-light, and Miracord had its soft-touch pushbutton controls since 1961. The new Garrards just seemed clunky.

Tonearm lowering in automatic play was abrupt, no more gentle than that of ordinary record changers. This probably wasn't as dangerous to delicate, light-tracking cartridges as it looked, but then again, it looked bad.

The much-touted "Auto-Rise" record support platform, which when functioning provided stable two-point record support as advertised, seemed flimsy. Sometimes, upon pushing the button to raise it, the platform would not lock in place and the stack of records would push it down again. Canny users soon learned that it was best to leave it up all the time; it provided virtually no impediment to placing single records on the platter.

The cartridge slides proved to be susceptible to intermittent contact. At the low voltage levels at the phono cartridge level, the results ranged from hums and buzzes to outright loss of signal.

On some samples of the SL95, the tonearm had a built-in azimuth error: a cartridge installed into the C2 cartridge clip would be tilted slightly when playing a record. How this got past Garrard remains beyond belief today. It could easily be "fixed" by shimming the cartridge to compensate, but the SL75 (at $20 less in the USA) and AP75 had a different tonearm...and it had no tilt.

Styling, always a matter of opinion, had gone from the chaste simplicity of the Lab 80, which seemed to imply quality by its very elegance, to a rather garish mix of shiny knobs, chrome-edged panels and control panel labels in both white and colors. The products of major competitors remained conservative and understated.

On the positive side was the patented Synchro-Lab induction/synchronous motor. Garrard had it all to themselves at first, but that was not to last long, as licensing of the patent allowed competitors to bring it to market. So Garrard was faced with having to update its brand-new product, beginning practically with its introduction.

The result was what I'm calling the "Large Chassis B" models SL95B, SL75B, SL72B, AP76 and AP95.

In all of them, the tab controls returned, though they were not sleek brushed metal as on the Lab 80, but moulded plastic; either plain black on the lower priced SL72B or chromed on the deluxe SL95B. They handled smoothly, with much less jarring of the unit; much better than the rotary controls of the older models. Additionally the control for the cueing device was separated from those for manual and auto play. Only the speed/size selector, which would normally not be used while playing a record, remained a rotary control.

The retractable record support platform became a non-retractable record support platform. Undoubtedly this saved cost in addition to being less fussy.

Tonearm lowering in automatic play was damped linking the auto function to the cueing device, so the arm and cartridge would descend gently to the record.

Styling was simplified; the control escutcheon had less chrome and blended more effectively with the black chassis.

Underneath the revised styling, the tonearm bearings for horizontal motion were changed. Previously the "large" Garrards used loose ball bearings in a race; with the "Large chassis B" models, an enclosed ball bearing assembly from a precision bearing supplier was used, resulting in lower bearing friction.

Nothing was done about the cartridge clip.

The Synchro-Lab 95B (SL95B) was the leader of the line. In addition to the overall changes in the "B" models, it had several improvements over the SL95. The counterweight was provided with a threaded fine adjuster replacing the sliding arrangement on the SL95 which was a retrograde step from the Lab 80. The tracking weight adjuster still could only be set by 1/4 gram increments but a calibrated scale in the Afrormosia wood insert made it easier to read. The azimuth error in the tonearm was visibly reduced. The SL95B was made in two versions: for the USA and other 120-volt territories a single-voltage version, labeled "SYNCHRONOUS MOTOR" front-and-center on its plastic trim panel; for other areas, a dual voltage version, labeled "INTERNATIONAL."

The SL75B had one minor change of its own. SL75 already had a fine, vernier counterweight adjuster. SL75B added a locking screw to prevent accidentally moving it.

The new SL72B was built to be a transcription-quality multiple-play unit with Synchro-Lab motor, at a lower cost. It had the small platter of the AP75, with a brand-new tonearm. A hexagonal aluminium tube supported a C2 cartridge shell. It had a simulated gimbal bearing similar to the SL95B's at the rear, a simple; rubber-isolated counterweight that was adjusted by turning it; and a tracking weight adjuster controlled by a knob on the back of the tonearm tube. A built-in tracking weight scale was mounted on the side of the arm. Although lower in cost, the SL72B's arm with its exceptionally low mass was probably the best-performing in the line with the high-compliance cartridges of the day.

The AP75 single-play automatic turntable was replaced by the AP76. It was created from already-existing parts: the large platter of the SL95B and SL75B and the tonearm of the SL72B. As was the AP75, it was powered by the Laboratory Series induction motor. It retained the inverted-ball thrust bearing of the AP75.

About a year later, the deluxe single-play automatic turntable AP96 was introduced. It also was made up from existing parts-bin items: the large platter, the inverted-ball thrust bearing, the Synchro-Lab motor, and the wood-trimmed tonearm of the SL95B.

The Module SLx-3 combined the small platter and Synchro-Lab motor with a simplified tubular tonearm based on that of the Garrard 3500 (but longer to suit the large chassis and with less tracking error), with a dedicated Shure M93E cartridge. In the USA it was prepackaged with a USA-sourced plastic plinth and matching dust cover.

Photos:

SL95B (USA version)
SL95B tonearm detail (early version before dual antiskate calibration for spherical and elliptical styli)
SL95B International
SL75B in UK base
SL72B in USA base and cover
Attached Thumbnails
Click image for larger version

Name:	SL95B Pickering-2.JPG
Views:	827
Size:	116.2 KB
ID:	72514   Click image for larger version

Name:	SL95B arm detail.JPG
Views:	786
Size:	27.9 KB
ID:	72515   Click image for larger version

Name:	SL95B_International.JPG
Views:	882
Size:	91.5 KB
ID:	72516   Click image for larger version

Name:	SL75B british base-2.JPG
Views:	873
Size:	25.6 KB
ID:	72519   Click image for larger version

Name:	SL72B top w-cover.jpg
Views:	937
Size:	84.2 KB
ID:	72520  

GP49000 is offline