Yeah, the monkeys are quiet. :) Not sure if the drives have started shipping. |
Two completely different Teres animals. Older models can be fitted with the new rim-drive. As I understand it this is trickle down technology from the development of the new Teres direct drive model. From Chris's comments on the improvement it does seem like a worthwhile investment. Hopefully, we'll be getting some impressions soon. |
Idler wheels are not directly coupled to the motor and do allow a minute amount of slippage where as rim drive is directly coupled to the motor. I agree that the success of this application will come down to just how well the control loop is implemented.
The rumble issue as I understand it has to do with wheels being out of round, cheap cast-metal platters, and/or motor vibrations through the plinth. Anyway, I don't think it is a given that an idler or rim-drive is going to suffer rumble just because it is an idler or rim-drive.
I haven't heard the Teres rim-drive but I did have the opportunity to hear the direct-drive prototype. Even though it sounds cliche I'm going to say it anyway. It really was like lifting another veil and getting closer to the music on the recording. Ok, maybe not new technology in general. However, the direct-drive was very impressive and showed tremendous potential, but not cheap. So, this is perhaps a way to allow those who can't afford a Certus to still benefit from an advancement.
I really can't see Chris putting out something that he is not happy with and he seems to have pretty high standards. I remain curiously open-minded. Again, we'll see what the reports are when the "monkeys" get to start banging it around. |
Well, Willster. It's like this. Many of us have first hand experience with the high level of quality of Chris Brady's work. So, when Chris tells folks that he's developed something worth listening to many of us tend to take notice.
I can understand your questioning, but you are speaking from a position of having no knowledge of the direct drive controller that Teres has developed or even of how Teres tables sound. Many of us are using tonearms and cartridges that are several times more that the cost of this new drive unit. I guess it's all relative. |
One could do what I and others who were planning on spending this kind of money on a table did. Make a few arrangements with Chris, Thom, whoever else, get on a plane to Denver and listen to the products and talk face to face. Maybe that's not as good as getting the 'table in your own room but with the satisfaction guarantee I can't really see the down side.
And best of all you'll have a chance to meet some really great people! |
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. |
Pauly,
Just what is your agenda here? We've been blessed to hear your ramblings on physics and how non-suspended tables can never be the equal of suspended tables. That's the kind of discussion I'll never have with you again as it only makes you look smarter than you are and me foolish. Now you come here to this thread and instead of discussing the subject from a scientific /engineering point of view, you just start throwing stones about how you'd never do business with Thom, Chris, or any other small business. I read your post several times. Don't piss down my back and tell me it's raining. You meant that to be condescending because that has always been the tone of your posts. |
I'd like to get back to the original topic. Since there are no "Primate Reports" to read I guess I'll play along.
I'm sorry. I can't any of this "investment" argument seriously at all! C'mon, we're talking about depreciable consumer goods here! There's no investment. You'd better be spending play money on this stuff or you're going to be in the soup lines later in life. I can just see me taking this idea to my investment dudes. "Hey, guys! I've got this great idea! Audio equipment!" I'm sure I could still go on with my great idea even after they all tell me to take my business elsewhere.
It's o.k., Banker Boy. I'm sure your Oracle is a fine 'table.
Oh! And since we're waggling packages at each other, every time you use the internet, pick up a phone, turn on your t.v., your helping fund my toys. Thanks, Banker Boy! |
An interesting question. Maybe Teres will offer up some info.
I think that Teres uses a mix of oil and poly as the finish. I don't think the o-ring would wear it off, but it may cause a track to become visible after a while. There is not much pressure on the platter from the mylar belts so I wouldn't expect there to be much from this drive. Although it would be concentrated at on spot and not distributed around the edge as with the belts. The cocobolo is really hard, it machines nicely and can be threaded.
I wonder what a little wax around the edge would do? |
Don't forget there is also the benefit of high platter mass to counteract the negative acceleration. It is the weight of that spinning flywheel that stores energy and helps get the car off the line. Too heavy, the car is slower to build rpms. Too light, and the car doesn't leave as quickly. The whole system should be analyzed, not just the individual parts. Relative to those light-weight cast or stamped metal tables of the earlier idler/rim drive 'tables the Teres platters are 3 or four times the weight. As Swampwalker said, the high torque may be great for getting the platter spinning from stop but once the platter is at speed, how much torque is needed to maintain constant speed? Which is a state of near zero acceleration. The energy stored in a 30 to 40 lbs platter is helping a lot. The connection of the LP to the platter must also be considered. It does no good if the platter is marching along but the LP is slipping on the surface.
"by offering relative immunity to minute changes in platter speed that might other wise result from stylus drag"
I would agree with that. IMO, this is also why the mylar belts are superior to all other belts I've heard. They don't stretch at all. However, they can slip ever so slightly and that is where the door is open for the possibility of rim drive. Obviously, the next step up should be direct drive, and it goes without saying that every drive systems needs to be well implemented. |
Dgarretson,
That is along the lines of the point I was attempting to make. A given motor speed and torque in the rim drive system may have a range of platter weight that works best with that given motor. Then again, it could be testament to how well these heavier platters with mylar belts actually work. ;)
I think the extra gears of a reduction system are going to introduce more noise. IME, gears don't mesh silently and there will still be slop between the teeth. That is why the Lenco rubber-tired idler wheel can work well when everything is in good shape.
"Finally, issues of force and compliance surrounding stylus drag can't be too much different than issues regarding VTF. This is handled easily in a TT arm by counterweights & gravity."
I would agree with you on how easily this is handled except that so many tables/arms don't. Perhaps that attributes to the rising price structure of many 'table/arm lines? |
Me, too. :) But I'd also like to hear that from others as well. |
I hope this is ok to post here. I just found this posting by Mark Kelly over on AA related to this topic.
"The idler drive mechanism has only a few percent of the speed variability inherent in belt drive (due to the lossy transmission eg belt creep).
Most idlers make up for this by using motors which can't hold constant speed against variations in platter drag (like the stylus traversing the record). Anyone who says their stock Garrard holds constant speed simply isn't measuring it properly.
As against this, the short term speed stability of an idler is excellent due to the almost lossless transmission from a motor with a high amount of flywheel effect. Most people assume this is due to the motor having lots of torque but that's not the case.
The other problem is noise - an idler definitely transmits more noise than a belt and they can create extra noise all of their own if the bearings aren't perfect.
Altogether its a toss-up.
Mark Kelly" |
Well, it looks like Harry has jumped on the rim-drive wagon. He seems to be offering the option and down-playing it at the same time. :-O
http://www.audioasylum.com/audio/vinyl/messages/67/677755.html |
