Reliability concerns
Hello Persil,
I could not decide how to best shorten your text to use a quote, so I just did a simple post instead.
I have already stated this before, but these tables are more complex and there is a slight risk to owning them, but this level of complexity is necessary to provide a proper implementation of the concept. There is no escaping this fact.
Factors that affect reliability could probably be divided into two categories. Factors attributable to the manufacture, and factors attributable to the user.
The Japanese turntables discussed here have varying levels of complexity. The Sony PS-X800 being the most complex (that I know of) and the PL-L1000 and its Pioneer variants being the simplest (in my opinion). To be fair though, the PS-X800, despite its complexity, does not seem to have a glaringly awful reliability record and owners seem to be happy with them.
Complexity certainly is an invitation for poor reliability, but not always. If a complex device is engineered very well with quality parts, the reliability can be very respectable. On the other hand, if a very simple device is engineered incompetently, it will have a poor reliability record making it a frustration to own. If the user subjects a given device to abuse, and-or he does not follow an intelligently conceived protocol of care, there will also be problems.
The bottom line is that these machines (although more complex than the norm) can and do serve their owners well provided the above facts are understood. The fact that there are many who still enjoy these tables, many years after switching to them, I think says something.
You ask about noise ingress into the tonearm in these designs. There are several different drive technologies used in these turntables. The pioneer uses a direct drive linear motor. No reduction gearing is used for the carriage drive, so there is no possibility of a vibrating drive motor creating noise ingress issues. The Pioneer is a silent design.
The other designs mentioned here have slightly varying degrees of noise ingress issues, but I think it's safe to say that any of the top of the line models discussed here were engineered to have surprisingly quiet reduction drive systems.
It is important to remember that many belt drive turntables have a much more powerful (and therefore a potentially higher amplitude vibration source) platter drive motor whizzing away at fairly high RPM, and this is a vibration source that can ingress into a tonearm (pivoting or otherwise) just as effectively as a poorly designed SLT turntable.
You also ask about the servo's role in less than perfect tracking error control. Of course nothing is perfect in this world, however the amount of tracking error introduced (on a properly operating and quality SLT table that is) is of no real consequence. The PS-X800 is supposed to have an extremely low tracking error if you are really concerned about selecting one of these based on this requirement. Also remember, a pivoting arm will commit greater tracking error sins.
So if you are willing to play by the rules, there is no reason you should not be able to enjoy owning one of these tables, you just can't get careless with them. But we're all good about being careful, right?
Best wishes, Professor Bizzt
