What's the deal with idler turntables and do they have a place in modern HiFi?

Thom
Have you considered introducing a little series R Into the power supply and scoping the motor current draw to vicariously look at stylus drag as a function of motor current draw?

cheers 

"Torque should come where it is supposed to come from and thats from the motor. "

imo - the torque should come from the part the record interfaces with - the platter. 8^0

@mjperry (OP) I own a direct drive, idler drive, and previously a number of belt converted to thread drives.  My reference is a string drive.

You can see the idler drive I own on my virtual system. I think they are alot of fun (especially with rock music) and remind me of big American iron cars from the 70's.

Great in a straight line, but noisy. and hit that first curve and you realize the part that is weak ... the brakes.

From an audiophile perspective most noticeable on Classical music with big dynamic swings meaning big groove modulations followed by small. The wheel can't slow down, and gives you a little blip in the sound - an upbeat so to speak - that I personally feel imo that some like to call PRAT :^)
   
The above is a memory taken from a serious audiophile nervosa phase.

Again really fun tables, but you can't just buy a stock table and build a plinth for it. There will be a big learning curve.   

The best designs I have seen - imo - focus very heavily on decoupling the plinth from the noisy motor. Mine is multiple layers of different wood and has large voids in the 100 lb plinth where the armboards bolt to.

Hi Ct0517

Do you have a favorite string you use?  I has been playing with 10-14 guage silk.

Thanks Tom

Here's my two cents worth....I've had Rek-o-kut turntables that I have rebuilt that sounded so bad that you would give up records if you had to listen to them ......Save your money, buy a Rega....I would say buy a VPI but you can't get parts for them.......I also had Thorens, which play good some days and other days not so good.....Those old turntables are like time bombs, there always something breaking or slipping or smelling bad......BUY NEW......autospec

Okay, here's another version of the question...

I have a VPI TNT IV, which came with a single idler flywheel, (not the extra three you sometimes see around the edge; apparently, there are quite a few versions of TNT). The base has three holes for the weird three-point idler mechanism but mine doesn't have it. The motor drives the idler flywheel, which is very heavy and has a larger diameter pulley than the motor, then another belt from the flywheel idler drives the platter round and round. I'm sure the idler flywheel is designed to both separate the motor from the platter, and with its weight, damp any transferred motor vibration and speed variation.

Since VPI got rid of the idler flywheel for later models, I've been toying around and did that, too..

So what happened? Did the world fall apart?

Honestly, I can't tell the difference. And without the idler flywheel, the whole turntable "package" makes a much smaller footprint. With and without the idler flywheel, I've been using the odd but yes-it-works-great piece of dental floss to drive the turntable platter. And the VPI SDS speed controller in both cases (the only way to get 45 RPM), so the only A/B difference is eliminating the flywheel idler.

The base it sits on is very heavy and damped, and it's using the stock VPI spring-loaded isolation/leveling feet which supposedly aren't the cat's meow but seem to work fine for me. The stock 12.5 tonearm with a Shelter 90X cart.

Anyone's thoughts? Has anyone else tried just simplifying the drive that way? It certainly looks more steampunk with the extra belt and idler gizmo, but simplicity is appealing. What intrigues me is this is essentially what VPI did in later models.