New Teres Direct Drive Motor Available as Option

Doug,

While waiting for Verus I am considering adapting tape drive to the VPI TNT by machining new pulleys for motor & flywheel. In order to prevent tape crawl, would cutting 1/2" channels into the pulleys be desireable? What is the best material for a pulley (e.g. hardwood, brass, delrin)? I suppose you'd want something smooth but not slippery.

Currently to get traction I'm using three threads between flywheel & platter, and the stock round rubber belt between outboard motor & flywheel. This probably offers most of benefits of an all thread-drive system. By using threads to tightly couple the inertial masses of the flywheel & platter, the system is more stable & the motor has less work to do in dealing with the drag of the stylus. A rubber belt between motor and flywheel may actually help smooth out AC cogging & the flywheel should act as barrier to the rubber belt's torquing effects. In any case, the result is a much livelier, focused sound than you'd expect from a TNT. The only thing I don't like about it is the occasional pinging of the thread knots as they circulate through the grooves of the pulley on the flywheel.

With rim drive applied, do you think the ideal platter should be light or heavy? If heavy, it would be an interesting experiment to retain the flywheel and relocate it outboard of the Verus motor. The flywheel could be driven by a long tape loop from the platter. This would have the added benefit of snugging up the platter against the Verus motor capstan & centering the platter bearing. Centering the bearing was the purpose of the old TNT three-pulley system, which I needed to remove to enable thread drive around the platter.

Yeah, Pauly. Now why would I take your comment the wrong way. Thanks for giving me a real good look at who you are. You would not be able to get 100% market share in any market I'd be in because I can recognize your kind as soon as your mouth starts moving.

Emailists,

The Verus was designed for and tested on tables with platters ranging from 25 lb. (the 265) to 35 lb. (my 320) to 70 lb. (Cello's 360). A 20 lb. platter will present no problems.

According to emails from Chris, the performance jump vs. belt drive is inversely proportional to the weight of the platter. Lighter platters have less rotational inertia, so they benefit most. I don't know if the Verus has been tested on a platter as light as 20 lb., but one might predict the biggest performance jump to date.

Dgarretson,
The best pulley profile is very slightly convex, with a small flange at top and bottom. Like a spool of sewing thread bulging very slightly in the middle. The bulge helps the tape self-center. The flanges provide a safety backstop.

Low mass seems to work better than high mass, so try delrin and yes, make it smooth.

Your present setup makes sense to me. Seems like the best arrangement of those materials: linearity close to the stylus where it's most audible, isolation as needed farther away. Somewhere on the Teres site there's a diagram of how to tie something called a 'blood knot'. It provides a long, relatively smooth join that helps minimize pinging as the knot rounds the pulley.

Heavy platter or light? See my response to Emailists above. As for including the flywheel as you described, you'll have to try it and tell us! It would indeed be an interesting experiment.

Doug

+++ Now why would I take your comment the wrong way +++

Perhaps because you react to my posts without giving it proper thought? My statement was not meant in any derogatory fashion, and I am somewhat perplexed at unkind your response. But I choose to take no offense – you obviously did not do marketing 101 at school.

Faced with the choice of going with a known quantity (Oracle/VPI) with no up front expenses vs. suffering a total loss expense (airplane tickets, hotel accommodation and time spent) on a totally unknown (Teres/Galabier/Red point) the choice is somewhat of a no brainier.

As I mentioned in prior posts, if a viable audition opportunity was available, I would most certainly have taken the opportunity.

In order to gain new clients and keep existing ones, we go great lengths and expense. Expecting prospective clients to suffer an expense will not work at all. In short, if somebody wants to sell me a product, I expect them to suffer the expense to market to me and not vice versa.

And BTW, if you make use of a credit or debit card, you are quite likely one of my clients already. If not, my competitors are just like me. So I ultimately you probably do not recognize my type even when we make money off you.

Kind Regards
Paul

I bet it is a fine design. From the early days of DD motors being the standard cheap design, my worry would be rapir costs if something went wrong with the motor. It may be a silly worry with a motor this quality, but on a belt drive table and awful lot of things can be fixed by changing a belt. Short term flutter is something I find really annoying and the deveil of old DD tables, even the much (over) liked sp-10, was when the motor went bad, you basically threw the table away.

Obviously this has different qualities and froma good designed I can see it working. However, long term speed stability and rumble are tough issues to tackle.