View Single Post
Old 6th Nov 2012, 7:43 pm   #42
Join Date: Mar 2012
Location: Sonoma County, California, USA.
Posts: 405
Default Re: Garrard record player deck identification.

The Garrard 3500 begat the "Autoslim-B" series of autochangers and the SP25 Mk III (previously discussed). In fact, the Service Manual that was issued by Garrard when the "Autoslim-B" series was introduced was that for the Garrard 3500 with supplement sheets.

Its lack of automatic record size selection in record-changer mode signalled both a money-saving move and an increased attention to single record play. While fully automatic single-record play with the short spindle was present only in the SP25 Mk III, the record-changer models did have the facility to swing the overarm to the rear, for better access to the platter. However, doing this put the overarm into its DOWN position, same as if there were no records on the multiple-play spindle; pushing the control to AUTO on the autochanger models would simply result in the arm lifting up and returning to its rest. Records had to be played manually, with the arm positioned by hand.

Life was made easier by the lever-operated cueing device, which for the first time on the Autoslim-chassis was damped with viscous silicone fluid, for gentle lowering to the record surface. The early implementation of this feature, however, was not ideal. When the stylus was lowered to the record, the lifting platform was pushed downward only by the arm via its lifting pin, which meant that once the stylus touched the record, it didn't go down any farther. This could result in a drag on motion of the tonearm; no matter how slight, it was still there. When the "Autoslim-B" series record changers were introduced and I saw this, I was alarmed, finding it incomprehensible that a company like Garrard could have overlooked this design detail. Within a few months, a revised design was issued: a vertical extension was added to the moulded plastic lift platform and a hole was placed directly beneath in the tonearm base casting. In between, a small spring was installed to assist the lift platform in returning all the way down, totally clear of the tonearm lift pin so there would be no chance of any interference.

A spring-operated, adjustable antiskate device on the higher-priced models replaced the weight-operated design on the AT60, 60 Mk II, SL65, SP25 and SP25 Mk II.

The models in this series introduced the "Cartridge Clip," a lower-cost design replacing the plug-in headshell. Its sliding contact strips would be a source of intermittent signals, hums and buzzes afflicting Garrards for as long as the system was used. The version of the cartridge clip in the Autoslim-chassis "B" series was the C2.

Styling was more angular than in the prior years' models, in keeping with then-current trends.

The 40B was the "entry-level" model in the "Autoslim-B" series. It had a four-pole induction motor in the USA and a two-pole motor elsewhere. It had cueing, but no antiskate. Its tonearm was partially counterbalanced; the user-accessible tracking force adjustment required an external gauge but once so calibrated, markings at one-gram intervals aided adjustments.

The SL55B had the Synchro-Lab motor and antiskate, with the same arm as the 40B (and the SP20B, photo shown on an earlier post).

The SL65B had the Synchro-Lab motor and antiskate, and a fully counterweighted, dynamically balanced arm of the basic AT6-SP25 design.

The 60B was an SL65B but without synchronous motor and the round badge on the left front of the chassis.

The Garrard large-chassis "B" series will be discussed later.


Cueing lift platform detail showing modification with extension and spring (partly hidden). This is from SP25 Mk V but the modification was the same on all applicable models.
Attached Thumbnails
Click image for larger version

Name:	40B w-base and cover.JPG
Views:	1565
Size:	22.4 KB
ID:	72410   Click image for larger version

Name:	SL55B in aftermkt base.jpg
Views:	2160
Size:	66.4 KB
ID:	72411   Click image for larger version

Name:	SL65B.JPG
Views:	2068
Size:	55.7 KB
ID:	72412   Click image for larger version

Name:	60B.jpg
Views:	955
Size:	102.6 KB
ID:	72413   Click image for larger version

Name:	SP25_Mk_V_arm-detail.JPG
Views:	807
Size:	23.4 KB
ID:	72414  

Last edited by GP49000; 6th Nov 2012 at 8:06 pm.
GP49000 is offline