New TT ideas please

One thing I've learned in my DC motor travails is that there is a correct torque for a given platter mass.

When I experimented with higher torque motors - everyone in the multiple evaluation sessions I conducted agreed with me that the sound took on a harsh edge.

From this (and other experiments) I concluded - puny, but not too puny.

Now, as I've written both on this forum as well as my Motor FAQs page, every element in the moving system is a variable (belt, platter, bearing, lube, motor specs, etc.). Change any one of them and you need to start over with your evaluations.

AC motors are completely different kettle of fish, although I'm comfortable in asserting that there is a correct torque specification that will balance in a musically coherent manner ... IOW, you can have too much as well as too little torque.

There's quite a bit involved in optimizing these power to mass relationships, and like everything else in audio, the numbers are but a departure point.

We're a finicky lot, and our hearing has evolved over tens of thousands of years in a sophisticated manner which we're just beginning to learn how to measure.

Cheers,
Thom @ Galibier

+++ How does my suspension do all these things? By obeying Newton's Third Law of Motion. +++

With all due respect Doug, your response is no more than a cop out. The type of one liner I'd expect in a Micheal Moore documentary.

Newtons third law states “For every action, there is an equal and opposite reaction” and it acts upon all turntables, whether suspended or not.

Vibration (floor borne + stand) need to be controlled and damped before it gets to the record-cartridge interface. By introducing a suspension you can both control/convert vibrations to be less troublesome frequency AND turn some into heat.

A fine example of this principle is suspended high rise building in earthquake prone zones. By using suspension the energy of the quake is managed so that the building suffers a lot less damaging energy. The energy transferred to the building is at a frequency the building can withstand and tolerate.

On my Oracle, the floor/stand borne energy transmitted to my stylus record interface is converted from a spectrum of audible frequencies to 5 Hz ... way below what my system is going to responding to, and a lot lower than my cart/tonearm resonance. On an unsuspended turntable you'll get vibration throughout the frequency range.

As for the notion that the suspension interferes with the record stylus interface, that is equally bogus. The arm and stylus is a unit, and the suspension does not come into play.

+++ I did mention that a well designed, high mass plinth is needed to damp resonances on a non-suspended table.+++

Yeah, I had one. No low level detail until I put an air bladder suspension under it. Oops yeah, don't suspended turntables do that all in one?

Regards
Paul

"Luck Brand" no. His name is "Dollar Brand."

Sorry, that was a mis-type. I might have even put Lucky Strike in the state I was in this am... Thanks

Pauly,

Sorry for not explaining the Newton reference in my usual mind-numbing detail. Still, let's keep Michael Moore out of this. I don't know what kind of tables he likes and you probably don't either.

The problem I've noticed with suspended tables (again, not including the more expensive ones, which I haven't heard) had nothing to do with floor- or air-borne vibrations. It resulted from the suspension allowing plinth movements in reaction to cantilever excursions and arm movements. This sapped energy from the cartridge, slewed and slowed transients, muddied bass, etc. Sorry, but that's what I've heard. More than once.

Just yesterday I received this email from a friend who just received one of Thom's tables (switching from an Oracle, actually):

Toms bang more. Kick drums hold their decay but the low end and transient response is lightning fast especially for such a massive table.

I chuckled at that last, since it is the precisely his new table's mass and stability which give his arm a stable platform, which allows the cartridge to perform better.

Hatari,

I have a friend with a Clearaudio Master Ref (I think, the one with three motors and three rubber belts). He replaced all three with one Teres motor and one non-stretchy belt, and reported better pace and cleaner, faster transients.

Acrylic? Any stucture (platter, plinth, whatever) made from a single, homogenous material is going to resonate more than an identical structure made of a mix of different materials. Materials boundaries break up and reflect energies, so more materials can result in more energy dissipation. Different materials also absorb and release energies at different frequencies. With proper implementation all the above is to the good, since it will lower the noise floor of the table. Acrylic is used because it's easy to machine and relatively cheap - and many people like its looks. Teres used to offer all-acrylic plinths and platters. They stopped because they couldn't get the performance they were seeking.

The only weakness I can think of in a Redpoint (which I haven't heard) is that floating arm pod. Puts you at risk of unintended and possibly major cartridge realignments, possibly without noticing. ;-) If you can deal with that, I'd say give one a listen. Having a dealer near is a huge benefit, better than all the internet chats in the world!

Best,
Doug