Besides of various “Idler Drives” (EMT, Garrard etc.) you also find excellent “Direct Drives” (Denon, JVC, Brinkmann, VPI etc.).
Regarding “String” or “Belts” we have discovered improvements in the last 10 years, innovations with 2, 3, 4 motors (Acoustic Signature, Burmester etc.) or one motor & pulley combination (AVM, Acoustical Systems etc.).Why came this up and what are the real improvements?
I have one Direct Drive, the Denon 100M. The Continuum table has a very precise motor (one!) running with an elastic white rubber band. The Caeles II as well as my Micro-Seiki system with the special decoupled platter on top are driven by two motors, which are separated and not in touch with the table. You may notice with the Acoustic Signature or the Burmester that the motors are put on top of the ground plate.
DENON 100 M
ACOUSTIC SIGNATURE
BURMESTER
AVM
CAELES II
MICRO-SEIKI
CONTINUUM
ACOUSTICAL SYSTEMS
We know that two motors which are put in symmetrical opposite position to each other do produce an empowerment without overturning momentum. In case you are using only one motor you are at the risk of implementing a side force power. Some designs are using high calibrated motors reducing that kind of failure to a minimum extent, some others not.
The belt drive absorbs motor vibrations and noise which could be transferred to the needle. It also improves the cogging and the existence of changes in speed. Nevertheless we see a reduction of elasticity over time. Belt drive tables have a lower torque. With the Direct Drive you have a higher torque and less distortion.
The solution with a passive pulley on the other side and thus avoiding using several motors shows some advantages. Pully systems are quieter at high speeds and do not require lubrication. A further advantage of a pulley is that you can make them variable so for any given load you adjust one pulley, and it automatically adjusts the other so that the pitch circular diameter changes. Implementing two motors on each side you need to focus on equidistant distance and similar force which can be done if you watch it carefully over time.
We should not forget that the weight of the platter, kind of bearing, fixed brake and active motor management (VPI steering, e.g. steering modules of Acoustic Signature and Acoustical Systems) play a role in the whole context.
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The more motors, the more amplitude in rumble you’ll be adding. You can optimize it by higher grade, synchronization, matching selections, belts. But equally you can charter a plane to send an e-mail on a USB stick to a recipient in the next city.
Get your bearings right and do direct drive. Or simulate it with one motor+belt. See current EMT TT and other models of that little swiss group.
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Generally you are right. It depends on the quality of the motors, Sperling and VPI (See Micro Seiki) are on top of the quality steering. And of course belt quality is another topic. Acoustic signature is telling us that they have eliminated all noise and rumble in their design by electronic steering of the motors. Hifi Friction, the (not so) little company, uses a fly wheel as well on their Thales TTT- compact 2 as does Acoustical Systems at their A*Stellar design.
Best
E.
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As the still current fashion seems to be air bearings or the like there might be a rubberless air drive jet system, with air suspended platter, and air supported tangentional arm, systematically integrated and close controlled. I wonder why AI is not yet implemented to control the drives and jets based on the music depended recorded grooves forces, as they will vary and resonate. ;-). Your free of charge sunday joke. 😉
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so which one is the best sistema or which one do you prefer?
thanks
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I prefer all. The Caeles II with its wonderful airbearing design (a real one!, look at the compressor – two great arms with Lyra Titan and Kondo Io-M) the Denon DD usually for my Monos, the Micro Seiki with wonderful arms AS Titan, Copperhead, Kuzma and carts, Ortofon Century 100, Palladian and Ultra Eminent Bc, the Continuum with Cobra/Lyra Olympos and some three other carts in the SAEC WE-8000.
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