Systemdek III/IV Metal Platter

[Ruben1]

Is the metal platter on the III the same as the one on the IV ?
Thank you.

[markcass]

Is the metal platter on the III the same as the one on the IV ?
Thank you.

Hi

The answer is, "not quite". Both weigh about the same, approx. 10.5 pounds, and have a slightly dished top surface, to be used in conjunction with a record clamp to force the LP into intimate contact. However, the III's platter has a peripheral "wave trap" (a rubber ring on the outside, not present on the original Systemdek's platter) and a felt mat bonded to the top surface. The IV's platter has a thick vinyl layer bonded to the top surface, creating a "composite" platter and rendering a separate mat unnecessary. The two decks also had different types of matching clamp, but any clamp that fits over the fairly tall spindle will work.

HTH

Mark

[Ruben1]

Thank you for such a quick response.
The reason I asked is because I have a very nice IV with different platter and want to bring the TT back as close as I can to original but the only metal platters for the Systemdek I am seeing are for the III (I once saw one advertised as being an original transcription Systemdek with no other model number given so not sure exactly sure about the table as no other numbering was given).

Do you happen to know if the metal plate for the III will fit the IV? If it does would you be able to render an opinion on how close it would sound on my deck as compared to the IV metal platter.
Thanks

[markcass]

Hi

Well, I wouldn't like to offer any guarantees as to whether it would fit, especially since I only ever had a modest (but much-used and cared-for) Systemdek II, but these two images from the Gallery and
show, respectively an original Systemdek (close cousin to the III) and a Systemdek IV (early version with power supply built-in). You can see that the alloy sub-platter looks very similar in both cases, suggesting either platter would fit.

As to whether the III platter would give the same performance as the original IV platter, I couldn't say. Obviously, Systemdek's designers believed the redesigned platter was an upgrade, though it was only one of the changes they made to produce the IV.

One can't even be sure it would sound better than the acrylic platter currently fitted to your deck, as also shown in the Systemdek gallery. However, it would certainly offer greater rotating mass, which should benefit speed stability. Firm and generous bass was also associated by some reviewers with the high mass platter when the early decks came out. One must assume that the IV's suspension was designed around such a high mass platter, and would benefit from having one fitted; as you say, the change would bring your deck closer to the original. I'm not surprised you haven't found a IV platter, as the deck is pretty rare.

You would have to use a clamp if you don't already do so, as the III and IV both had slightly concave top surfaces, and the record wouldn't properly contact the platter without clamping. This wasn't the case with the original Systemdek, though, as the top surface was flat with an indentation for the record label.

HTH (a bit!)

Mark