New TT ideas please

Hi Pauly,

How does my suspension do all these things?

By obeying Newton's Third Law of Motion.

I had an unsuspended table not to long ago and it was less dynamic, had less bass impact and had a much higher noise floor than my Oracle. (It also cost more than my Oracle).

I suspect the sonic shortcomings were directly related to the fact that each and every micro vibration was dumped straight into the cart, something not happening with my Oracle.

I suspect you're right. There was clearly something amiss with a more expensive table that couldn't match a less expensive one. I did mention that a well designed, high mass plinth is needed to damp resonances on a non-suspended table. Maybe your previous table lacked that?

Motors & belts:

You're right about motors of course, they're vitally important. Clearly a "puny" motor, whether DC or AC, will have more trouble resisting stylus drag than a more robust one. And a noisy or cogging one will be unsuitable for direct torque coupling to the platter. (Can you imagine a direct drive with a noisy or unstable motor? Ewww.) The best of all motors would be powerful, quiet and would provide constantly linear acceleration, not a simple task.

We may have to agree to disagree on motor/platter coupling. I have experimented with at least 10 different belt types, on two tables and with three different motors. This was with platters weighing 25 and 35 lbs. respectively, far heavier than an Oracle's.

Despite these hefty platters the differences between one belt and another are invariably audible. Elastic belts ALWAYS stretch on leading edges of transients (that's what "elastic" means of course), and a more powerful motor simply exaggerates this. After reaching full extension, the elastic then seeks to return to its resting state on the trailing edge of the transient. This is also audible. Slippery belts (silk thread, silk tape, etc.) also degrade the sound. When a transient increases drag on the belt/pulley interface, a slippery belt slips. The effect is pretty similar to the leading edge stretch of an elastic belt, though there may not be any rebound on the trailing edge.

High rotational inertia cannot overcome stylus drag. That's a physical impossibility. All it can do is lower the frequency and amplitude of induced variations in rotational velocity. That may dampen stylus drag effects but it will not audibly eliminate them. A strong motor with a linear torque coupling to the platter is the only way, at least IME.

Best,
Doug

Doug: thanks for taking the time for your response. I purposely left beuty and musicality as features there - knowing that only I can determine those :) But you certainly did address the rest. What about platter? Do you have a view as to whether a solid acrylic platter (a la Clearaudio Master Solution) or a metal/hybrid platter affects my desired outcome? Also, the belt thing is always interesting as so many pretty "high end" TTs have belts (again, the Clearaudio Master Solution - rumoured to be quite a lively table, BTW).

So your view would be that a Clearaudio Master Reference (same price as these names generally) would lose energy/liveliness and muddy transients relative to those brands mentioned. Are there European brands that fit that bill (ie Transrotor Fat Bob?). From a design perspective (and it matters) Redpoint is the only one that works for me from this bunch. We do, oddly, have a local Redpoint dealer.

Thanks

I respect Doug Deacon's knowledge and contributions to these threads.

However, it is unfair to paint belt drive and/or suspended turntables with such a wide brush.

There are belt driven suspended turntables that will stand toe to toe and even outperform the brands on his list based on the parameters he's chosen. Some of them even cost less.

Disclaimer: retailer

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