Direct drive vs belt vs rim vs idler arm

I have checked a few, but mostly I have checked motors that are commonly used. I was surprised.

Well, I'm going to put my vote in for the Trans Fi Audio Salvation direct rim drive tt (with Terminator T3Pro linear tracking tonearm).
I'd been running a belt drive Michell Orbe/SME V for 10 years, and investigation of uber pricey belt drives like the SME 20/30, TW Acustic AC3, Brinkmann La Grange /Balance etc showed an incremental improvement, but not enough to go with the upgrade. And, this in tts costing $20000-$40000.
But I then came across the Salvation, and wow!
I'm NEVER likely to go back to belt. I'm getting a unique combination of the best of analogue ie bloom and tonality, with an almost digital-like accuracy and neutrality.
It's unlike anything else I've heard when playing vinyl.
Getting away from belt related speed drift really produces a fantastic unwavering solidity to music, most noticeable on rock solid piano notes, even as they decay away in the soundstage, and no audible wow and flutter as lp side end approaches. Previously I would always be aware of fluctuations as piano played, especially individual notes, but not anymore, and often I'll be suprised that I haven't picked up on side end groove modulation as the stylus plays the last few seconds of the end of sides.
I've run a thread on the tt/arm giving a more in depth appraisal of my experience.

Spirit, Have you tested the Salvation TT speed stability with Timeline?

I agree with SYSKOS, that Timeline results of members' various TTs would be a very useful grade scale (pass or fail).

For a Timeline test to be truly useful, some standard should be applied. For example, I saw a DD table tested with the Timeline. The owner held a piece of paper behind the turntable and demonstrated that the red dot did not drift during the 20 second test. I asked him what would happen if he let the dot fall on the wall about 4-5 feet away and waited five minutes. He admitted that a further distance would show a drifting over time. A video with a set distance of the laser dot to a wall, say 5 feet away during a period of ten minutes, or with the stylus at the beginning, middle and end of an LP would be good, but I don't want to have to watch a 20 minute video showing the entire length of the LP. Perhaps a fast forward feature with a time stamp and mark on the wall for some kind of consistency would work. Also the test should start with the stylus not contacting the LP and then during the test, it should be lowered onto the LP.

I agree that the results would be interesting, though I really wonder if the speed variation of a successful KAB strobe result versus an unsuccessful Timeline result would be audible. My table shows a steady result with the KAB and I have not had the opportunity to borrow a Timeline.

I would think that any manufacturer who has a design which passes a Timeline test would want to show such a video for marketing purposes. This issue came up in another thread about speed accuracy and someone asked about the accuracy of the Timeline device itself. If the strobe is slightly off, but the table is accurate, the red dot would also drift slightly. Measurements are only as accurate as the measuring devices themselves.

The timeline has a quartz clock. It is accurate, according to Ron Sutherland, of two parts per million. That's very good, and I have no reason to doubt him.

I don't know the limits for other drive types, but it is theoretically possible for an idler to be accurate to around one part per million, so my controller was designed for that. You could go further with a GPS referenced OCXO clock in the controller, but could anyone hear it, and could the device keep up with the clock?

At some point we have to question the merit of it all because there are mechanical limits. And, just because a turntable has a great clock doesn't mean the turntable spins accurately, and just because it spins perfectly in the lab doesn't mean it will do it under every condition, in every environment. Still, I believe it is the responsibility of a manufacturer to get as close to perfect as he can given the price point of the machine he is selling. If you pay small money, you aren't going to get super accuracy, but you may get a very musical turntable that is consistent. To me, that's worth a great deal, although I personally try to push the limit to its threshold. Essentially, you should get what you paid for.

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