Vintage DD turntables. Are we living dangerously?

Lew
The rubber grommets look original.
I will PM you a pic of the stator to compare with yours.
Inserted in the centre of the grommets is a small metal tube stand off to prevent the grommet from being crushed when the bolt is tightened.
There are also a couple of nylon? stand offs to prevent the rotor from contacting the stator windings when the platter isn't in place ( partial mag lev feature)
Anyway, slight stator rotation is permitted by this arrangement and if original it is an interesting design decision.

Lew,
When Lurne was working under contract for Goldmund I imagine there were constraints. The T5 linear arm wasn't held in the highest regard and the DD suspensions were problematic with any arm substitution. Many users including myself defeated the suspension. The Studio came with alternate springs, but most users were clueless about how to substitute.

This is the first I've read of problems with speed stability. These are quartz locked with a JVC motor. Perhaps you're referring to the earlier Pabst motor, but the ones I've heard didn't seem to have speed problems if everything was functional. The Reference was servo controlled belt drive.

Lurne is probably the most copied TT designer in audio. Not sure which Audiomeca you're referring to, but take a look at this design including the suspension:
http://www.tnt-audio.com/sorgenti/belladonna2_e.html

Regards,

Fleib,
Many years ago my friend took his bog standard L07D over to Richardkrebs who at that time had a heavily modified Goldmund Studio. Despite the Goldmund having had many power supply and other modifications and an ET2/Monster Alpha cartridge and the L07D a cheap moving magnet - the L07D highlighted significant speed problems in the Goldmund, particularly in timing and coherency. The Goldmund by comparison sounded like it was lurching around and struggling to get over the line. This is what I believe prompted Richardkrebs to dump the Goldmund for the SP10mk3 that he now runs. I believe that Goldmund had the JVC motor.

I have heard the Krebs modified SP10mkII and to my ears it is similar to the Goldmund Studio, well down in performance compared to the L07D and SP10Mk3, again in loss of timing and coherency. I think it is significant that both the L07D and SP10mk3 utilised higher mass platters than their earlier DD's to assist with speed stability.

And yes by DJ I meant radio stations and the need for quick and accurate queuing.

One further thing to be aware of - out of the five people I know with L07D's, only one has had no "apparent" problems - quartz locking not working properly, hum, noise being the most common issues. So when we audition some of these decks today it is possible that we were not hearing them optimally as they were designed simply due to ageing and drift in components.

Lewm I have heard both the L07D and SP10mk3 with and without the Krebs tweak and agree with your summation, the proviso being that the TT's have been serviced thoroughly and are performing to spec. Bear in mind though that the SP10 requires a lot of work to get it sounding ok - new plinth, mats etc.

Dover,
Can't say I accept your anecdote about the Studio as being typical of performance. I've heard a few and your description of "lurching around" suggests a malfunction or improper set up. I no longer own a Goldmund so I have nothing to defend, as audiofools typically do. The Studio isn't an easy table to set up. Your description suggests lateral movement from the suspension and/or platter wobble. If the table had the T3 arm that could have been a source of the problem. I didn't use their arm. I had a Zeta.

The DJ comment was Pryso's. Actually, the 1200 came out in the early '70s and was a consumer deck as were all with the SL designation. It was adopted by both the broadcast industry as a cheap backup deck, and mostly by the dance music DJ's. This was a time before digital and using a record player at a dance was typical.

Technics was aware of their sales and the use of the 1200. They redesigned the deck in the late 70's specifically for DJ use. Still light enough for portability, yet ruggedized and practically shockproof. The SP25 and 1200MKII are the same deck. The SP25 is for console mounting or in a separate plinth and the 1200 is a DJ deck. That's the way it is. How do people think the 1200 got the way it is, by coincidence?
Regards,

Fleib, My gross impression of the Audiomeca that I heard on many separate occasions was that it suffered from what I now think of as an ill of belt-drive, maybe a stretchy belt or maybe its bouncy suspension. Some in those days used a compliant belt and mounted the motor on the stationary chassis whilst the platter was suspended, a great set up for speed variation as the platter suspension responded to the environment. However, this may be unfair criticism, since I do not know how the motor was mounted in the Audiomeca. Anyway, the sound was "woolly", for want of a better word.

Dover, My Mk3 is mounted in a ~100-lb slate and cherry wood plinth, and I have implemented a massive bearing damper much like that used by Albert Porter in his Panzerholz plinths. Of course, the L07D plinth I've left alone, apart from updates to the feet.