I haven't got perfect pitch and my friends tell me my timing aint that good, but I find piano recordings fantastic for laying bare speed and VTA issues. The words clangy and compressed come to mind when things aren't well, assuming the recording is ok to start with.
Regenerated ac supplies are quite cheap and accessible today and possibly an easy upgrade for tt's with simple supplies.
Love the US$6000 VPI Classic III - Fremer says its one of the most speed stable belt drives he has heard - the supply consists of 1 cap and 1 resistor. Be interesting to run the timeline on one. |
When I am playing Vladimir Horowitz on my turntable should I ask him to stop on the half hour Eastern Standard Time so I dont have to listen to the speed corrections ?
Seriously though when I was selling Elite Rock Townsend turntables which used an AC motor, when I corrected the operating voltages from 69.9 to 70 volts, even though AC motors are supposedly dependent of frequency not voltage, the sonic presentation changed from that of a Van den Hul to a Koetsu without changing the cartridge. Something was going on - motor resonance, optimum torque, minute speed changes - who knows.
Atmosphere is right there are many things we hear that are not measurable.
A sinewave doesn't tell you whether the pianist was happy or sad when they hit the note.
By the way the 0.02 is the correction of the AVERAGE fequency deviation - that is quite different from the real deviations in frequency. |
Halcro - you are being disingenuous. The Fat Bob has a stretchy elastic band for a belt and furthermore the drive from the belt is close to the bearing. By not driving the circumference of the platter a lot of purchase from the puny motor is being thrown away. I think you will find this is a classic German pisstake of the Harley Motorcycle, after which it was named, and which you are very lucky if you make it round a decent corner. |
Halcro - great demo, no accent.
I agree with Lewm on neutrality, different for different folks. We all know if we have a preamp with a dip at 3k say and we listen to it for a long enough, the ear/brain adjusts, and when you try something else that is neutral you think it has a peak at 3k.
I would suggest that speed and timing are far more important, as once you have lost the timing you cant recreate it in your head.
Re Wave Kinteics NVS that started this thread - did anyone notice that that original thread has disappeared. Do manufacturers get bad press/comments pulled from the forum ?? |
Catastrophe u missing .68 of a revolution - try 60 / 33.333333 |
Tonywinsc,
For records with holes out of centre my engineer mate simply uses a thread file ( very small round file ) to open the hole up only in the direction you need to move the record to centre it. Then puts a marker on the label to indicate which side of the elongated hole butts up to the spindle. This seems to work reasonably well. |
Raul try testing the timeline it goes like this - - - - - - - |
Halcro great to see you trying the thread drive. The pulley shape should be concave for thread drive so it self centres and does not ride up and down.
Dev I have been using my thread drive final audio Parthenon for over 20 yrs with silk thread , surgical silk, quite high tension and there is only a very faint mark on the platter, no wear. |
Dev - the Final Audio platter material is aluminium with very heavy copper mat. The thread runs on the aluminium part. I would have thought the copper is harder than aluminium and should be safe but not absolutely sure. |
Halcro, you have done a fantastic job bringing us up to speed on this and also leading the way on trying alternative ideas on your Raven. However I must pull you up on a couple of comments on DD
"The differences between the two drive types I believe, has to do more with the speed of any correction applied once a deviation is detected?
In this.....a belt or thread drive is at a severe disadvantage.
The DD motor....usually with a lot more torque than that of a belt/thread drive....and being directly connected to the platter.....can correct deviations in micro-seconds theoretically inaudible to the human ear."
Thread drives do not self correct as DD's do.
Didn't your mother tell you 2 wrongs don't make a right ? You could argue a DD is twice as bad as a thread drive. One assumes if there is a time slippage and it is a one off why stuff the next few seconds of music trying to catch up ?
Then there is the correction of the correction when the DD overshoots on correction.... as my learned engineer tells me, nothing wrong with DD's they are only a little bit out all of the time.
"The DD motor....usually with a lot more torque than that of a belt/thread drive"
This is a presumption, I'm not sure it is correct. I'm not sure how many DD's could spin my 20kg plus platter up to speed in less than one revolution as does the AC motor on my thread drive.
But to balance the argument I still lust after an SP10mkIII for a second deck.
|
Lewm,I struggle with this statement -
"among designers of both belt- and direct-drive turntables there seems to be a divide around weak motor/huge platter vs strong motor/light(er) platter"
I have never associated high mass platters with low torque motors.
If you had said the 2 schools of thought were light platters with sophisticated speed correction or control versus high mass platters with more inertia and less speed correction that would be a more accurate synopsis in my view. |
Re the Kenwood L07D and the Technics SP10mk3.
In understanding the design we must remember these turntables were built for quite different purposes or use. The L07D was an all out assault to produce a state of the art tt for home use. The SP10mk3 was designed primarily for broadcast and archival use. Consequently the L07D has one of the most sophisticated plinths of any tt manufactured in terms of rigidity, energy dissipation and ease of adjustability for accurate set up. The SP10mk3 has incredible torque, very fast start up and stop times and a crap plinth.
We dont know what was in the minds of the Technics designers - the choice of the mk3 motor may have been more to do with the fact that it was the motor used in cutting lathes and readily available at the time. What is interesting is that when they increased the torque they also increased the weight of the platter significantly from the SP10mk2. |
Albertporter,
This is astonishing, you are saying that every Timeline shipped is calibrated to your SP10mk3.
So if your SP10mk3 is out all Timelines shipped could be out.
Didn't you just "prove" that after calibrating the Timeline to your SP10mk3 that this then proves the Timeline is accurate because your SP10mk3 gives the same result when retested.
I think I need a drink.... or a shrink. |
Albert Porter/Halcro
Bit slow today, so I had a drink, Steinlager Pure Blond, much clearer now. Cheers... |
Halcro, it is a tragicomedy, perhaps the brass and woodwinds are just not getting on with the stringed instruments.
Could be any number of reasons, but most thread drives are designed with high mass platters and very small concave pulleys. I have the Final set up such that there is no slippage with the silk thread, ie quite taut, and if I turn the motor off the platter will drive the motor/pulley quite easily for a while. I still have concerns about how well the 2 motors on the Raven are synchronised. As you have highlighted our ears are better than many measuring instruments. If the thread is taut it is more direct coupled than a rubber belt which could magnify motor drive issues. Purely conjecture of course. |
Halcro - great game eh. Looks like Dokovich has shown the others how to beat Nadal - ie hard and flat if they can maintain it.
Re the bearing, it's a bit of a red herring - I only meant to communicate that in the case of the Final there is high inertia such that if the motor is turned off and the belt/thread is still connected the platter will drive the motor/pulley for a few seconds.
Lewm's capstan is a good observation, the thing that interested me was that if you add a capstan and get more belt/thread on the pulley & platter it will spread the side loading on the bearings of the motor & platter. This would potentially reduce motor bearing wear. |
Halcro - looks like the 2 threads are touching. If so you might want to put a shim under one of the motors to lift it slightly and separate the threads. Would be interesting to try 1 motor/thread. Cheers. |
Atmasphere - I think you are too optimistic on the quality of the US power supply. The US grid is split into 4 quadrants and the supply agreements in place with the power providers have delivery standards etc, but there are NO standards in the agreements on frequency stability. As you will know frequency will vary with load fluctuations on the grid. I have seen figures of 60hz with an accuracy of 5%. This issue is currently being investigated. |
Lewm,
Which of the 3 tt's the Lenco L75, Technics SP10mk3, Kenwood L07D do you find the most musically satisfying. Have you ended up with same or different sounding decks, or through choice of arm/cartridge deliberately tried to dial in different strengths ? Which one assuming all are speed accurate do you feel gets the most off the record. |
Lrsky/Lewm - my money on an 80's demonstration by Magnepan would be an Oracle Delphi tt with the Magnepan unipivot tonearm, this was a popular combo of that era in the US if you weren't in the Linn/Sota camp. |
After all the hoopla about the NVS, that was deleted, this is the update from Albert Porter, who is an authorised seller.
"Perhaps you forgot, that table was the one damaged in shipping. So in addition to the inferior wooden arm boards, it's bearing was not functioning 100%. Pretty easy for the new one to defeat it."
Isn't it amazing, that after all the proprietory study into energy control, better than any other tt made, they suddenly realise the wooden arm board is not a good idea. Makes you wonder. |
Albert - I love more new tt's coming to the market. It just seems the hyperbole doesn't match the performance. In this case the claims made for energy dissipation in the design seemed at odds with using wooden arms and armboards. I'm not sure stainless is that great either, but as you will have experienced most arms have resonances and different armboard materials will sound different and either add to or subtract complementary resonances.
Most often ignored in these forums is that the turntable/arm/cartridge form one system and ideally the 3 components must have a common purpose in structural design - either dissipate energy or sink it to ground. Turntable, Cartridge or tonearm comparisons should always be referenced or qualified by the other 2 components but seldom are.
Back to the NVS, the optimum arm board material will vary depending on the material used in the arm/arm mount and the material used in the NVS frame to ensure minimal energy is reflected back to the cartridge/record interface at each junction. |
Lespier,
I run the Final Audio Parthenon ( heavy patter/thread drive/AC motor with reconstructed sine/cosine wave power supply ). Just waiting for the 1st shipment of Timelines to arrive in New Zealand. I'm not losing any sleep, my references for speed accuracy -KAB,Test Record, solo piano stability of notes, and using Digital Sources as a comparison are fairly comprehensive. Oh and forgot I have Technics SP10 Mk3 for comparison as well ( Still not losing sleep ). |
Halcro - welcome back. Australian politics has been very entertaining of late. Are you putting your hat in for Foreign Minister ? |
Grr6001 - No one ( to my knowledge ) ever stated it was better than any other TT.
Jonathan Tinn had stated in his system ( which now seems to have disappeared) :
"The Wave Kinetics NVS Direct Drive Turntable is absolutely in a league of it's own. Having a great deal of experience with the likes of the Rockport Sirius III, Continuum, SME 30, Forsell Reference, Grand Prix Audio Monaco, VPI HRX, Nottingham Hyperspace, Basis Debut, Lodo Audio The Beat, Kuzma Stabi XL, Vyger Indian Signature, Walker Proscenium and many others, this turntable is truly unique. It is immediately noticeable. "
There was no declaration of commercial interest.
However it is time to move on. |
Doesn't this discussion on DD servos highlight the question, does a very high mass platter, with very high inertia, driven by a high torque motor with a belt, thread or fluid drive with built in slippage, such that the platter mass will drive through any load fluctuations sound better than a DD with its constant speed correction.
Correct me if I'm wrong, but isn't the need for servos because DC motors inherently do not respond in of themselves to changes in loads.
For those that are keen to experiment - here are a couple of decks worth trying :
Rossner and Sohn - latest special custom-made turntable is called The Mott (The Mother of Turntable). The rotating platter itself weighs 232 kg. Choice of air or oil bearing.
Sati - 50kg platter, interesting comments on motors on their website. |
Lewm, I meant DC motors. As far as I know the following DD's use DC motors - EMT948, Technics SP10mk2&3, Sony PSX9, Kenwood Lo7D, Exclusive P3. The Denon DP100 uses an AC motor.
DC motors react to variable loads quite differently to AC motors. Seems to me there is potentially as big a difference generated by DC/AC motor choice and implementation as there is by drive type.
Actually, I believe I'm right with regard to DC motors - DC motors do not self correct when speed fluctuates, hence the need for servos or speed sensors at the very least. Question is as Brinkmann suggests there is a trade off on sound "quality" between fast recovery and soft recovery type servos. Too fast and you get overshoot and more correction.
Platter mass also factors into the equation as well in that it can dampen the servo action in a DD TT.
There was no argument or generality suggested, but a question posed if you reread the post. |
Lewm, no worries. I think there is a lack of real info as DD manufacturers and vendors placed more focus in their advertising on the fact that it is DD. I know the SP10mk3 and Lo7D well and agree with your descriptions of the difference in sonic signature. The Denon DP100 looks very interesting. |
Albert, I know the engineer well who designed the mods for the SP10mk3.
Will be very interested to see your feedback. One point to consider, you may be better to get the bearing mod and review the impact before the electronics mods, or you will be unable to discern what has done what. You wont know whether the bearing or electronics mod is a positive or negative unless you do one step at a time. |
Hi Albert - no that sounds fine. The engineers modus operandi is that he overbuilds everything, which is great. I have heard the SP10 mk3 but unfortunately in a system, which although I have followed the evolution, I don't know what is doing what. That's why I'm interested in your feedback. Your bearing mod makes sense to me, wicking the energy away. There may be advantages to your solution in that if the energy is higher up the frequency scale a harder conduit ie the rod into the lead may be more effective than just sinking the bearing directly to a lead block. Unless we AB it we'll never now. The electronics should be fine if Bill is OK. Good luck. |
Hi Henry -
Have finally managed to try the Sutherland Timeline on the Final Audio TT ( heavy mass - platter 19kg, string drive ( single silk thread ), AC motor driven by oscillator preamp( reconstructed sine/cosine waves) and power amp.
Testing with and without the record playing I have to adjust for stylus drag.
Both the KAB and the Timeline show the stylus drag. The net movement of the laser with stylus drag is about 2mm on the wall per rotation.
If I correct for stylus drag with the KAB then recheck with the Timeline it is spot on.
With record playing the Timeline is spot on as per the KAB.
Conclusions are I can sleep at night, and the KAB, or at least my one, is as accurate as theTimeline.
|
Atmasphere - think of all the "wear and tear" of all the drive train over 70 odd years. I think whilst we have gained in technology, we have probably lost ground in metallurgy, it's the age of junk metals ( PC & non toxic manufacturing processes required ). I still marvel at the lack of main bearing wear in the Final TT which is now over 30 years old.
Love to hear playback via a lathe and good old Mcintosh MI200's that I lusted after years ago.
Lewm - distance from wall is 400mm if you want to do the maths.
Henry - just to say thanks for the inspiration - your video challenge has really upped the game for die hard analogue folk. |
Lewm - I positioned vertically a silver metal marker, about 25mm wide, on the wall - it was quite easy to check the moving distance from the leading edge. |
