New Teres Direct Drive Motor Available as Option

Paul, I think you misunderstood my intent. My main point was that we need someone who is or was in the record-making business to tell us whether Ketchup's point has any validity. And I am only saying that my guess is that it does not, but I admit I don't know. Now you have cited your empirical and subjective experience to contradict me, while also saying that this type of evidence is not acceptable. Your opinion is certainly as valid as mine, but one would need to know more about cutting lathes to settle the matter.

Lewm,
First, you say that stylus drag might be a good thing. It might, but there is much more to it than stylus drag. My instincts tell me that a cutting head cutting a lacquer puts much more drag on the lathe's platter than a modern stylus does playing vinyl. The trick might be to use a lighter platter than that of the cutting lathe and, along with a stylus, hope that the speed variances are about equal in magnitude and duration.

Second, I would love to hear what some people in the record making industry have to say about speed variances in cutting lathes, but I fear whar I might hear. I think a lot of people into "pro audio" seem to think that we're nuts and that we shouldn't hear any difference between A or B, whatever they might be, or that we couldn't possibly hear something so subtle, whatever it is. How often have you heard that?

Whether my point has any validity or not will take A LOT of very careful experimentation that I bet will NEVER be done, but let's for a second assume that it has no validity what-so-ever and that cutting lathes are rock solid with respect to speed stability. If we assume this, then all the rim drive (Teres), mylar or tape drive (Galibier/Teres) belt drives with massive platter (Maplenoll/Walker) turntable designers are just wasting their time trying to reinvent something that has rock solid speed stability and has been around for years.

Hi Ketchup. Agreed. I think it is folly to believe cutting lathes have perfect speed stability. I came across this site where the sell cutting lathes. http://www.vinylrecorder.com/index-e.html. One of the tweaks they offer is a 3.8 kg platter to reduce wow and flutter.

I guess like everything else in life, not all cutting lathes are equal. Some would undoubtedly have less stability that others.

Lewn, my bad – I do not mean to be combative. I understand your point BUT nobody can really prove that stylus drag decelerates a platter to soften transients. We accept that as it is based on sound physics and what some folks have heard seem to tie in with that. A cutter slowing down the cutting lathe is based on the same physics. You cannot simply accept the physics for the one and reject the same physics for the other.

Also, I am not saying what I hear is proof that this happens, rather the cutter drag on the cutting lathe goes a long way to explain something I have heard on some of my LP's. I may be totally wrong, but I think physics back this one up.

Regards
Paul

Pauly,

The flywheel effect of the platter on that cutting lathe would be negligible compared to the 75kg/cm torque generated by the motor. From pictures on the net it's evident that a really decent cutting lathe like the Neumann has a much stronger drivetrain. A lathe strong enough to handle the fundamental drag on the cutting tool should be impervious to small modulations in drag. Still, somehow tools never quite seem to be as good as they should be. I have a metal lathe with a 10" chuck & a 2hp motor & I still manage to find jobs that are too big for it.

I did find a reference to pitch problems introduced by stylus drag on lathes used to cut 78rpm records in the 1920s.

"....could have been torn out of my earliest - and current - writings on the subject....."

Occasionally, some of us forget that johnnantais single-handedly invented the idler table. Fortunately, we can rest assured that he'll always be here to remind us of his place high on top of the Mt. Olympus of Turntables.