Is this the best tonearm in the world?

It's a shame that data is from the 60s with 60s carts, stylus profiles and tracking weights using test discs with constant (sic) velocities. Very interesting though.

I think we need measurements on real discs played by typical stylii. Try and repeatably see dynamic drag and ideally any consequent dynamic wow.

 

It makes sense, in a way, as both stem from a similar origin.

The initial Onkk relied on a (fully) reworked Audio Technica DD motor, which is in a way, let's put it subtly, "an homage" to the 1970's Technics products. I have no way of knowing what is the technology inside the OMA, but I doubt there are many more ways to slice a cake with a DD motor, not in some way experimented by Matshushita already.

I would be very interested to conduct a similar research - especially when it says in the report "...developed a simple method... ...without the need for a special equipment." Is there a longer version of the report where the method is elaborated upon?

 

You're running a synchronous motor. The speed will only change (unless you stall it of course) due to belt stretch or slip. But it could still wow dynamically under a changing load.

 

I still have them all, but fixing up the links seems a task not worth pursuing.

 

Presumably in the 1981 AES Journal article? Need a member to do some reading.

I did a very crude experiment last year with a spare LP12 and a DC motor. Using an ammeter you can measure the current required just to turn the deck, with a stylus playing an outside groove and inside groove. All differ as expected. The problems though were irritating. I have an Origin Live pulley that is wrongly formed. The speed wandered up and down cyclically due (I infer) to the belt wandering up and down the pulley's camber. The ammeter has a significant impedance, so extra load reduces the voltage and speed even more than naturally due to the motor. However if these are compensated for you have a direct measure of the power change when the stylus is lowered. Hence the drag.

I did show though that a single magnet near the platter added drag at a level much greater than that produced by the stylus.

 

This discussion proves that we like the science to prove what we like to hear. The Luka Bop founder(in a vid earler in the thread) had it it right when he said he preferred the sound of the idler drive (I think it was a Thorens) so would not change. I have had mainly belt drive (Linn, Rock, and Brinkmann) but I prefer the sound of my direct drive Grand Prix which just makes music sound more alive.

 

More off a completely off-the-wall (or perhaps on-the-wall) approach courtesy of a recent post in another audio forum.

Thought about starting a separate thread but the tonearm and rotation characteristics seemed to fit here.

The Wheel turntable: https://miniot.com/

 

Exactly. Not sure I have much intuition on how they work. But moving a conductor through a magnetic field generates a current, and a current produces a magnetic field, and due to conservation of whatever those fields are opposed, hence brake. It's a bizarre effect, it seems much stronger than it should be. There's probably Youtube of dropping magnets through tubes. And Veritasium has a nice example in his latest, although that's not exactly a magnet with an audiophile purpose.

I don't know where to start with the maths but I did wonder about whether it was possible to produce an eddy current drive operating directly on a non-ferrous platter. I don't think there's been a direct drive mod for an LP12 yet and it would be quite raddical.

 

All things being equal, ill still take an AC motor driving a heavy platter through very thick oil fed from a high quality regenerated sinewave. No motor cogging due to high load from bearing and cart drag gets swamped by viscous drag in the bearing rendering it moot.

 

Fascinating thread.

I beg to differ...

It was Fleming and "Lee De Forest" with the introduction of the third electrode added to use as a "Control Grid" inside an evacuated glass valve light bulb to prevent / attract away the soot burning off the light bulbs filament, that caused a darkening / coating the inside of the evacuated glass envelope and accidently created the Triode and with it the Diode.

From then on started the Electronic Communication Industry.

The first ever possible control of the free flow of Electrons.

Secondly, it was the 1951 discovery / invention of "William Shockley" and the use of Semi-conductors "Germanium Transistors."

William Shockley - an overview | ScienceDirect Topics

The "Cat Whisker," clever fellow, imho.

Then NASA, that was only possible because of the two previous World changing events via Fleming and then later Shockley.

Back on topic, the best sounding tone arm to date to my ears was the Decca Unipivot c/w the magnetic bias clipped on to the tone arms pillar, the tone arm was fitted with a Decca SC4E.

All of which was mounted on a Garrard 401, flush strobe light version, mounted on a quarter inch thick cast iron slab, cut outs to fit in the 401, no plinth just a massive motor board, I wish I still had it.

 

There is a tonearm that has very few adjustment that can be made, simple design, and ignores all the received wisdom associated with the design and set up of a tonearm. The Viv. This is a plonk and play tone arm that ignores everything i have been taught about tone arms. I had the pleasure of having the 10" and the 7" on an extended loan (no I am not a reviewer) and used them both on my Verdier. Quite remarkable . They hosted the Dynavcector X1-t, IO-m and Allaerts carts. I eventually preferred the 7"! Incredibly musical; no distortion on the inner grooves of large classical orchestral music, wonderful tone on operatic voices where you could hear how the singer was controlling the note.

So: SIMPLE, EASE OF USE, NO ADJUSTMENTS APART FROM VTA, GREAT DESIGN, INTERCHANGEABLE HEADSHELLS, NOTHING TO ARGUE ABOUT ON FORUMS, PLONK AND PLAY. But It challenges our preconceptions of how a tonearm should work

 

Be careful of taking too much advice from that. He did a reasonable job on the belt and idler theory, but clearly doesn't know much about direct drives.

The idea that the electronics industry has only been able to generate a clean, low distortion sine wave in the last few years is particularly laughable.

 

Don;t get me wrong, Tony, I agree that the new Technics methodology is certainly a big improvement on some of the rather more hair-shirt approaches taken in the 1970s! However, even precision software control isn't new - Vestax were controlling their DJ turntables' direct drive motors using 32 bit CPUs over 15 years ago.

I'm also curious as to why he sees fit to mark down one of the negatives of direct drive as "Most existing implementations subjectively underwhelming"

I'd be curious to know which sample decks he bases this statement on.

 

Hmm. I'm going to have to do more listening, but I regard my 1210G, Garrard 301 and Well Tempered Amadeus as being pretty much on a par as drive systems. I can't really hear speed fluctuation on any. I use the same arms/cartridges on each, although my Amadeus has the theoretical advantage of an 11-inch arm. In terms of pitch/tunefulness, grip, slam, energy etc I would not be confident of being able to distinguish them blind. If I were to try, I would listen for the compelling bass drive of the Garrard, but I have no confidence that this is not just an idea in my mind. The other two decks also seem to have effortless drive, by different mechanisms. Probably the best chance of distinguishing them with a good pair of headphones would be to listen for motor hum (Amadeus), rumble (Garrard) and background silence (Technics), but it's down near the recorded levels of those noises on many records, so I think I would still struggle.