Dear Kirkus, there was no way to put that design into a commercial product. Too big (the Caliburn, Goldmund Reference, Micro 8000, Raven etc. were all dwarfs in size), too heavy, too much periphery, your wife would have shoot you and divorce (not sure which first...) upon the sight in teh living room.
And no way for trickling down in more convenient size and financial frame.
Anyway - I will do it once more this summer and autumn and will include a few technical devices which I could not integrate 20 years back. I will post the pictures and specs of the turntable in late autumn here on audiogon.
For all to share. |
That implies that the suspension should go as low as 0.5 Hz to ensure isolation from building resonance. I'm not so sure on this -- after all, at 0.5 Hz the relative stylus-to-record motion *should* be fairly well attenuated simply due to the fact that it's now several octaves below the basic cartridge/tonearm resonance, which is acting as a 12dB/oct high-pass filter. From emperical evidence, the cartridge/tonearm resonance envelope definately affects the sensitivity of a boingy suspended turntable system to foot-falls and such. So I'm thinking that the primary suspension mechanism of importance is its Q, and flatness through its transition region . . . so it doesn't add any additional peaking to the tonearm/cartridge resonant peak . . . the exact rolloff point for the suspension simply needs to be a bit (an octave should easily do) below the that of the tonearm/cartridge. The best results will then be acheived because the slope of the attenuation (provided by both the suspension and tonearm/cartridge working together) is smoothly increased, without increasing the peaking, and the ultimate attenuation at very-low frequencies could be similar to the system you describe. Another huge issue is how the suspension behaves with horizontal shock, in addition to its vertical behavior. I think that this is THE main flaw in the Linn/AR suspension, and just about every turntable suspension that uses compression springs. In these systems, since the mass of the subchassis sits above its support points, it's inherently unstable with regard to external horizontal motion. This fits with the long-time Linn recommendation of the Sound Org stand for floorstanding applications . . . something will minimise the addition of horizontal energy, yet cleanly transfers vertical energy to the turntable, where the suspension does its job the best. Ideally, it seems that the subchassis should be underhung with respect to the fixed chassis, resulting in a stable, predictable horizontal resonance . . . and there's probably some perfect relationship between the horizontal and vertical resonant frequencies that would allow horizontal shock to be converted to vertical spring deflection (through pendulum action). |
Well, we do not have to re-invent the wheel here. All this research about suspension has already been done by industry with huge amount of manpower and technical resources. These problems are solved.
We just have to apply them to the turntable system and/or its benchtop / stand platform.
The only problem is: they do not come cheap (as any "good" turntable cannot come cheap....) .......
Have a look at the website of Minus-K and/or Kinetic systems or any of its market competitors.
What will do the work for an electron microscope will do the work for a turntable.
The better of these benchtop platforms will isolate from vertical AND horizontal vibration.
Foot-falls and usual household vibrations from washing machines and in-house motors are not the problem.
The problem is the all-present buliding resonance.
It was an eye-opener for me to actually "see" what isolation from enviromental vibration really means - and what it can do.
If we can agree, that the idealized working conditions are very similar for both turntables and electron microscopes (both "working" in very similar nanocosmos dimensions) - then we already have the solution.
In easy words: you do not have to worry about suspension at all if you put the turntable in question on top of a professional vibration isolation benchtop platform precisely resonance-adjusted to the weight of the turntable in question (and for god's sake - do NOT place any standalone/detached motor-drive on the same platform!).
Borrow one or try to get one from technical scavangers (there are enough companies around selling of the remains from technical-orientated companies getting out-of-business). I bought a good benchtop from Kinetic used via ebay for 1/20th of the list price (o.k. the transport from North Hollywood to central europe was a few bucks too, but not that bad).
Well - a really "good" new isolation platform will cost the same as any of the "avarage" turntables alone.
If the technical aspect and waypath alone are not enough proof, I recommend to all (for once..... to support the technical outline) following Raul's advise: listen to it.
The immediate apparent difference in sound-presentation will tell the story.
As I still am sure that we do work with techincal facts and issues only in the design of a turntable - the turntable "done right" will never come cheap.
If you are into off-shore boats or high-end rifles or high-end motors - no matter where - if you are looking for the "best" in those they won't come cheap either.
You just can't fool around with physics.
In the design of those topics just mentioned - are we dealing with taste or guesswork ? Maybe in the outlook, the cosmetics - but never in the technical design.
In turntable technical design (NOT cosmetics or appearance) its all physics - and honestly, there are moments when I do not like that fact either ........ |
Thanks for the info, Dertonarm . . . I enjoyed reading about these products.
But it's not a matter of "re-inventing the wheel", its a matter of understanding the exact requirements so as to make sure we understand how well the solution fits the application, and the problems we're trying to solve. Because (to use a silly example), putting your tomato plants in the finest laboratory glassware doesn't mean their fruit will taste any better.
Most of these off-the-shelf devices (i.e. the MK26) appear to have a low-pass characteristic that somewhat resembles a Chebyshev response, which trades some pass-band ripple or peaking for increased performance in the stop-band . . . I'd speculate that this is an excellent trade-off for most of the laboratory applications for which they're sold. But for a turntable, the low-frequency peaking of these products may indeed cause some problems. I'm sure they still sound excellent . . .
. . . but if you truly want to do a turntable "right" as you say, then simply sticking i.e. an RX5000 on an off-the-shelf Minus-K platform doesn't cut in my book. Using existing laboratory-instrument technology might be a good approach . . . but if you want the BEST performance like you say . . . a custom-designed product that had its stopband/passband performance tailored specifically to a turntable application is what you should be after. |
Dear Kirkus, - well a Micro RX-5000 on a (specified for the Micro 5000's weight load) Minus-K is already a different beast.
The one vital point is, to really use a platform only, which is specified for the exact weight of the turntable in question.
One problem is however, that all the benchtop isolators do only perform their best with fairly heavy load (at least heavy for a turntable...).
As the better ones are designed to work with fairly big (= heavy = expensive...) microscopes and similar costly technical measurement equipment (= the users have little limit on spending extra to get their instruments show their best....... as always - they are all "in it for the money"...).
However your proposal to carefully tailor laboratory-instrument technology hits the point. It is exactly what I am doing in my spare time the past 2 months. |
Dear Kirkus: I agree with you on the subject.
A TT design are develop on many " factors/characteristics " that have an intimate relationship that makes almost impossible to build the " perfect " TT and like in almost any audio item design we have to choose the best trade-offs and these trade-offs are the ones that make " the difference " but almost every TT designers have its own trade-offs priorities and to be more complex that TT designs comes to a different customers that have its own sound reproduction priorities.
Yes, we can make a TT design near " perfection " according our own technical trade-offs and the ones are not so technical but that have some kind of influence.
About, isolation: how can we aisle the TT from the SPL of speakers in the room?, maybe looking for the lower SPL in that room or taking the TT in a different room where means a different kind of trade-offs. In a TT " perfect " design we have to think about and in many ther obvious factors and other no so obvious ones.
Here we are talking on macro-isolation but there are micro-isolation that are way important too, we have to remember that the cartridge is a very strong " micro ". You point-out the importance of the arm board and I can add ( example ) the importance of a TT mat and we can go on and on. Interesting.
Now, we can put the best technical know-how on the TT design but we have to test on laboratory ( truly expensive ) and in a second step ( critical ) we have to test it in our own laboratory: ears/brain, not an easy task, each one of us has a different " approach/attitude " in the same subject!
Thank's to those human been " differences " exists different/many TT designs out there, good thing.
The subject is how the TT designer can improve ( near perfection ) its own design, it want to do it? are enough TT customers that could pay the price for that " near perfection " TT to make commercial business? can the market/customers understand the advantages on that " near perfection " TT?, I think that exist too many questions and too many different answers to each one question.
As we can try to go " in deep " on the subject as more questions come " alive " and this is almost with any audio item design.
I know ( like Detornarm ) what I'm talking about because in our Phonolinepreamp we already be " face to face " with all those " problems/trade-offs " ( and many others ) and we stay right now in our tonearm design: complex for say the least
Regards and enjoy the music.
Raul. |
and that's is " simple " task because there is only one person on the design but what if there are two-three-four persons on the design and everyone with the same " right " to make an opinion valid.
I know the big " trouble " here because some times in the design one or more opinions goes against each other and we have to be very very open mind to make the " final " decision on the subject below discusion. Not easy at all.
We " face " many other issues: exist the technology to build what we " think " on the design ? are there the build materials/parts in a precise way we need it? can we manufacturer if not?, questions/answers like these have its own trade-offs.
The design/build of any audio item is a real and hard challenge for everyone but big corporations like Matushita Harman and the like.
Regards and enjoy the music.
Raul. |
Dear Raul, yes - a different room is the one and only way to isolate any turntable effective from SPL radiated by the speakers. No doubt. However - this has nothing to do with the turntable design itself. It is a matter of the enviroment/position. Put the turntable in the next room and drill a hole through the wall to allow exit of the tonearm cable or the NF-cable(s) from preamplifier to poweramplifier(s) - è voila!
But - a turntable can be designed to "near perfection".
"Everything possible to be believed is an image of truth " (William Blake , end of 18th century).
Its a matter of consequence, effort and energy put into the task.
However - a "near perfect" turntable can NEVER be a commercial design.
A space shuttle will never be a commercial product either (not as comparism here, but to clarify the point...).
Neither can the "near perfect speaker" and its cousins the "near perfect preamplifier, poweramplifier (always in close relation to the crossover and efficiency of the speaker) etc "(well, the pivot tonearm and the cartridge - that could work in the narrow frame of market-conformity). Any other commercial audio product will be - and was so far - always a (often more and rarely less) dreadful bundle of compromises (god - I hate that word since childhood!!).
To come anywhere close to the "near perfect" in audio components means in plain simply words:
- leave commerical audio products and the idea to bring that "near perfect" designed audio component to a "market" behind.
It will not work.
You have to do compromises to bring ANY product on a "market".
There is no free lunch in high-end audio neither.
Well - theres an old saying: nature knows no compromise.
Compromise may be indispensable to keep our past zenith society working as long as possible.
If we accept all too easy compromise in the development of audio components we will always get what we deserve and have gotten so far:
.....mediocrity...... |
Here is one of these 15 units, a pic from a High End Show, it was bought right away, when I remember right. Probably to a Single :) WAF free Zone |
Ghosts of the past.........that particular unit is from 1993.
The base plates are corian on dural with polyurethane layer.
80% of the technical periphery is inside the integrated "stands" of turntable and motor unit (including active air suspension, surge tanks, automatic leveling.
Dimensions were 4 feet wide x 2.2 feet deep and 4 feet high. Total weight approx. 580 lbs.
Every wife's nightmare.
The motor unit does feature selective air supply for up to 3 airborne tangential tonearms (adjustable pressure and amount of air - these were the days of Air Tangent and ET 2 back then.....), adustable air supply for active suspension and radial / lateral air-bearing. All speeds 33, 45 and 78 are precisely tuneable.
And this was 1993........ |
Dear Dertonarm,
My compliments.
Being the son of an architect has certainly paid off with a design that even the Bauhaus would be proud of?......but I know that only the laws of physics determined its appearance? :-) |
The string "belt" on the mammoth turntable in the photo is WAY too long for optimum control of platter rotation, even if the string has no stretch at all, but I guess the inertia of the humongous platter mass compensates for this problem to a degree. I am also guessing that the very long distance between motor and platter is an exteme attempt to isolate the platter from motor vibration, a la the Verdier on a grand scale. Nevertheless, it is a "compromise". IMO, it is impossible to avoid all compromises in any design and in any other human endeavor. Wherever there is a choice between two options that each has its own justification, there will have to be a "compromise" with respect to some feature of the desired outcome of the project. God help the perfectionist. |
Dear Lewm, we can not achieve perfection - we can only try. The long string is no compromise at all. Yes, the string has no stretch at all (a special kevlar derivate). The point is not control of the platter rotation. The point was to prevent the platter from loosing any speed. Control is futile. The platter must be stablized by inertia. Control and correction in speed will always result in a constant error-correction-loop. Thus creating instability and a constant change in speed. I think this is a clear fact - everybody into technical affairs and physics will agree in this after giving it enough thought. The inertia of the rotation platter is so stable - you can't even dream getting that stability with any direct controlled (= speed control both positive AND negative by the motor via direct coupling ) platter (dd, idler or belt drive).
I certainly do not want to start any philosophical disscusion here, I just tried to illustrate the point that all too often we go for a compromise WAY TOO EARLY and WAY TOO EASY.
Compromise in our culture is a positive term - because it helps to accept unpleasant facts and things the way they are.
For me compromise is another word for surrender.
I think we should not accept surrender (=compromise) too early - without trying our very best. |
Dear Halcro, thank you very much.
To speak in the words of an era in architecture we both do favour: .....form follows function..... ;-)) |
Dear Dertonarm: Do you still has in use that TT with you>?, btw: which analog rig/electronics/speakers are you hearing/playing/enjoying?, could you share with us?
Thank you in advance.
Regards and enjoy the music.
Raul. |
Dear Raul, right now I am in the process of building the successor of the turntable Syntax has pictured. This project will be finished in autumn this year. I will include some thoughts and technical features I either could not include back in the early 90ies - or which came to mind in the last years.
I did not post any pictures of my system, as it would not help people to get an idea. Aside from tonearm and cartridge none of the other parts of my system are commercial products. However - I will briefly describe the system.
The preamplifier is all tube. Split passive RIAA. First 2 stages are full differential stages (1st time constant of the RIAA is equalised here). Between 2nd and 3rd stage the other 2 time constants are eq'ed. The 3rd stage is a pure plate follower. All triode. The line stage is full passive with transformer attenuator made by friends in Japan. Output impedance is pretty constant 120 Ohms. It drives several meters cables and 3 different pairs of amplifiers in parallel (and live athmosphere, rich colours and live-dynamics are my prime focus in playback audio). The preamplifier is full hand wired with all silver. All tube sockets are mounted on individual PTFE platforms in open frame architecture. All resistors are Shinko Tantal. All capacitors are silver foil in oil. The whole open frame arcghitecure of the Phono circuit is itself suspended inside the 2 cabinet preamplifier by special soft rubber anti-vibration poles. The powersupply is full dual channel with 4 rectifiers (double single wave) and all PP power capacitors with dual bifilar choke LCL filtering. All selector switches are massive silver TKD. Total 6 phono inputs with various transformers to accommodate and match any given source impedance and inductance by any moving coil and MI or MM.
The whole system is tri-amplification. E
ach woofer is sealed cabinet, 18 to 80 Hz with 500 Watt amplifier with active DSP. The woofer driver is a 18" unit with an BxL of 32 and maximum excursion of total 28 mm in sealed 70 litres. Mid bass and mid-highs is a 2 way system with 8" field coil paper driver with huge choke power supply and 80 000 µ filtering. 12 V supply. The tweeter is a 28 lbs unit which goes from 800 to 45 000 Hz. A ribbon / planar hybrid with 100 dB efficiency (past crossover). These two are mounted in an inverse ultraflex cabinet with a combination of 1st order electrical x-over (1 coil in low-mid - 1 capacitor in mid-high) in conjunction with approbiate mechanical filtering in low-pass (pre-chamber) and high-pass (super short tactrix). The cabinet itself has a special adjusted build-in mechnical high-pass with -3dB at 80Hz. Thus giving a pretty smooth melting between the active 18" woofer and the 8" mid-low driver. The whole system has measured 99.5 dB efficiency. Max. SPL 128 dB. Phase never worse than 8°. Pretty flat response whole band.
The amplifier for the tweeter is a special 8 Watt 1 single pair bipolar concept designed by STAX/Japan in 1980 but never commericalised. It has a double 12V - 2 000 000 µF power supply, soon to be put on complete battery supply. It is capable to deliver 5000 A for short moments. The amplifier for the mid-low (80 - 800 Hz is a single ended MOSFet design with OPT. 11 Watt. The shortest signal path of any amplifier. Very similar to the Western Electric type 25 amplifier of the 1920ies, but build with a special MOsFet and matching huge Output-transformer. No input stage, no driver stage.
Tonearm is - no surprise - FR-66s and cartridge is a very special FR-7f modified. Cables are Audioquest SKY w/144v DBS all in NF and flat ribbon pure silver for the mid-high and mid-low.
But honestly - I do not think that this description is of any help.
It rather illustrates the point that I am not too impressed with the offerings of the industry but like to go my own ways. |
Wow, thanks for the picture, Syntax. Very, very cool work, Dertonarm. Since we're hitting on the subject of "how do we pursue perfection" . . . this is of course a difficult question, both in the defining and the persuing. I think that there are several of us here who are frequently travel on this obsessive road in one way or another, and it seems to be ultimately a reflection of one's concept of their own mortality. And I've always enjoyed how much audio and music parallel each other in this capacity. But to lighten up a bit (I attended a funeral yesterday), there are always a couple of big obstacles in the pursuit of "perfection", the first of which I'll call the "Hubble telescope phenomonon" . . . where a focus on the tiniest of minute details causes one to completely miss the end goal -- that is, a telescope mirror with an amazing level of polish on a micro-level, and a huge macro-level flaw that goes completely unnoticed. Dertonarm metioned the Eminent tonearm, and I'll use this as an example -- great low friction, but horribly excessive horizontal mass (not to mention dirt-sensitive). The other common problem occurs with high-budget, limited-production projects. . . where from a true perfectionist standpoint, the contribution of every single design, material, and manufacturing decision must contribute maximally to the performance of the end unit. But the "cost no object" attitude actually can work against this, as there's the temptation simply to throw money at a given problem, because after all . . . what's mere money when perfection (and ultimately immortality) is at stake? And in reality, the assumption frequently gets made that simply because a problem has received great financial attention, that it is therefore solved. Thus, the input of cash has distracted the builders/designers from the required process of analyzing its contribution. Both of these are what I feel are some of the currents that drive up the cost of our hobby, without necessarily driving up the quality of the experience . . . and that's very much away from what I'd consider perfection to be. As Dylan Thomas said: The force that through the white thread drives the platter
takes my green dollar; that blasts my bank account
Is my destroyer. |
Dear Kirkus, yes, I have put some money in that project back then, but I got paid back and in the end I did not loose any money on that project.
As I usually do like to link philosophy with my audio discurses, I must however admit - not today . I am not in the mood - I am afraid. Most likely it will brighten up again tomorrow... ;-).
So rather plain and straight speak now.
So far my odessey in audio has been - on the large scale - cost neutral. I rather wanted to illustrate my point that all too often we do give in too easy. All the money I did put in that project in the early 90ies did not come easy. As I certainly always had to work for my money I wasn't too tempted to throw it away. I did put lots of work into that project - much more than money.
I wasn't on a field campain just to bring as many troops as possible on the battlefield as to crush the enemy by simply overwhelming him by sheer number and brute force.
From the plain dimensions this may look as just another gigantic egomatic turntable where weight and money were the driving forces and the brain was replaced by the big wallet.
Certainly not so.
Cost was an object indeed.
Sadly enough - I do not have money to burn.
Not back then - not now.
Being self-employed means you work everyday and on your own (your own risk too....).
I am certainly much more on a budget regarding my audio passion compared to several other Audiogoners.
Thats why I designed my own turntable, amplifiers and speakers.
Because I am on a budget AND because I did not find what I was looking for.
There was much more research put into that project than my mere words and the picture can tell.
It may however give some reason why I am not too impressed by the "state of the art" turntables of today.
Maybe I just want to say:
I know what I am talking about ............ nothing else.
BTW Raul, one sample of the turntable was in Mexico City from 1993 to 1998. The owner was (and still is...) the former director of BMW Mexico. I sat up the table in your impressive city.
P.S.: agreed on the ET2 - it was just mentioned to clarify the point why the TT had several individual adjustable air supplies for the many different designs in airborne tonearms around in the early 90ies - all having different needs. |
I wasn't on a field campain just to bring as many troops as possible on the battlefield as to crush the enemy by simply overwhelming him by sheer number and brute force.
From the plain dimensions this may look as just another gigantic egomatic turntable where weight and money were the driving forces and the brain was replaced by the big wallet. I didn't mean to insinuate that these were at all your motivations, my apologies if it came across that way. I was simply trying to give a little counterpoint to the general discussion, and make the point that the consideration of cost isn't necessarily anathema to the pursuit of perfection. Lewm did bring up the string . . . I'd appreciate it if you could explain some of the dynamics involved here, as I don't have much experience with thread-drive turntables. While the mid-1980s Micros and such are designs I've always admired and enjoyed listening to . . . I've always been a bit mystified as to how such a thing as the alignment of the pulleys, the tautness of the string, etc. (which strike me as critical parameters) were left up to the end-user to get right, when there was obviously so much effort into removing variability from so many other aspects of the mechanical design. Also seems really inconsistent with regards to temperature, and wear/stretching of the string itself. Are these significant factors, and does it ever bug you that maybe with sub-optimum setup and maintainance, your designs over the course of the years may not be delivering the performance you designed them to have? |
Dear Kirkus, I know that these were not your motivations - I just wanted to set some points clear as the turntable sure looks like a "mammoth" in the picture and thus the above mentioned suspect might easily arise. But - thank you.
As for the string - just briefly and preliminary, as I have to leave the computer soon:
The basic idea / principle is to have a homogenous mass put into constant rotation and then let the inertia do the job. The string in its kind of "slip-coupling" (which is kind of tricky to set-up and needs a calbrated spring gauge to ensure the perfect "non-grip") does have only one job (after bringing the platter on constant speed once):
- prevent the platter from getting slower.
All I can say - and this time I just plain ask you to take my words for granted - is: it works extremely well. We made long period measurements in MTU in 1992 and the derivation from 33 1/3 was (short-period as well as long-period derivation measurements) as close to zero as possible (measurements were taken with laser beam and calibrated circular stroboscope foil).
And - yes, the measurements were made while stylus was in the groove.
This is a huge inertia (the platter is 326 mm in total diameter - 108 lbs) in motion.
Once in motion on the desired speed, there are no derivations. The air resistance, the bearing friction (...the stylus drag..) these are all constants and thus the rotation stays constant.
It however takes about 2:35 minutes to reach constant speed........
The string just have to be dyneema or kevlar derivate and the coupling has to be precise.
But it works marvelous and watching it work, you get a certain "feel" of "completeness" and "natural move".
Audio phrases......
Time to get off.
Good night for now. |
Dear Dertonarm: Thank you about your system, very nice. No public comments from me other that : yes, for me is of some help to understand ( between other things ) part of your whole audio " thinking/mind ".
Regards and enjoy te music.
Raul. |
we can not achieve perfection - we can only try. The long string is no compromise at all. Yes, the string has no stretch at all (a special kevlar derivate). The point is not control of the platter rotation. The point was to prevent the platter from loosing any speed. Control is futile. Some months ago I tried different belts after reading the article from Conti (BASIS Audio) about it. I bought a few from different Manufacturers and made some test runs with the Micro Seiki 5000 (Belts from Raven, Basis, DaVinci, Amazon, Kuzma, Roksan, Transrotor, Seiki original....and even various ) Strings..... The result made me curious, because there were big differences in sonic presentation (smeared Details, dull bass, different depth of soundstage etc.) Even with string was different among themselves (slip, grip, noise etc.) This was a very interesting experience for me. Some belts are really lousy, I was dissapointed, there are much discussions about more motors, or powerful motors...after all, I am smiling about that. The goal should be to find the few, who do it right. I mean, really doing right. No talking about that (most "manufacturers" today prefer doing this). When one or he other reader want an upgrade, before selling the whole Turntable, try this first. Could be interesting :) Belt Test 1Belt Test 2String Test 1 |
Ah, yes!
a = (2*f*sin(x))/mass
Thanks for the trig review. ;-) |
So this futzing-about with various types of belt media and such . . . I take it that this is pretty much "de rigueur" to get the best from any turntable that uses the thread-drive approach? What did i.e. Micro Seiki originally intend for the RX/RY-5000 system? |
Syntax, In that third photo, is the platter on the right driving the platter on the left, as it appears? This is in keeping with some of Mark Kelly's teachings on "belt creep" and how to prevent it. Anyone interested in this topic should search on the Vinyl Asylum archives for Mark's ideas. He is a brilliant guy who applied math and physics to belt drive and who compared the different qualities of idler-, direct-, and belt-drive to each other, also on a math and physics level. Far be it from me to speak for him, but based on my understanding of his findings, a very long thread between a very narrow diameter pulley and a distant platter is not a good idea, likely to result in significant belt creep compared to other arrangements, such as using one platter to drive another, using capstan type devices to force the driving string to conform to as much of the circumference of the driven platter as possible, etc. |
Micro Seiki has a kind of tape (SF-1 Series) with an enormous grip, it is very sought after these days. It was in my comparison among the best. (After 25 years a quite impressing result) There are more options with the Seiki units out there. Seiki "Shot Gun 1"Seiki "Shot Gun 2"I was influenced from the original Micro Seikii HS-Inertia unit Seiki InertiaAnyway, the way I do it works quite well and there are differences in sonics with/without. A good "tool" for comparisons. But depressing. For the others. |
I went through Mark Kelly's extensive teachings. Good research and explanations, but he is not focussing upon the center point.
Some people will hate me for this, but I want to postulate a short and clear statement ( and I ask everybody to give it some deep thought before telling me I am wrong....) regarding ANY principle in turntable drive (idler, dd or belt):
The motor of a turntable has ONLY 2 jobs to handle.
1.) bringing the platter on speed
2.) preventing the platter to slow down once it has reached that constant speed
There is nothing else the motor / drive has to do.
Physics and logic will result in a huge inertia ( = huge mass of platter) providing an extremely constant speed by its own rotation. It will too result in a coupling which does allow some slip at BOTH ends of the drive system - platter AND motor (such that little variations in speed generated by the motor itself will NOT make it onto the coupling device (string, belt - whatever). A say 35 -50 lbs platter on 33 1/3 rpm rotation has a VERY constant speed (much better in its constant speed stability than almost all motors in use in todays high-end turntables).
It is not about control between motor and platter.
The platter will not get any "faster" once it has reached its determined speed.
It gets slower due to air resistance, stylus drag etc. But those are constants in real world application.
So - all the motor and its coupling device have to do is preventing the platter from getting slower.
This automatically does lead us to a definite slip coupling and a huge inertia.
The way to get ultra constant speed and practically zero derivation in as much inertia as possible (in real world application).
Give it a deep though before jumping to the keyboard telling me a stupid, narrow-minded fundamentalist.
Its all about masses in motion.
Again - its all physics.
The trade-off is a long time to arrive at stabilized (2-4 minutes) speed. |
As for the Micro Seiki original belt / strings. The Micro Seiki RX-5000 came first with a fairly strong and wide rubber belt of very high quality first. However they did recommend too - right from the start - using an aramide string ( made out of 134 individual fibres ) to get the very best results possible.
Because of less vibration transmission towards platter - and: slip coupling....... resulting in much better constant speed....... |
In fact Micro Seiki 's engineers were the very first to realisze the potential (in turntable design...) of high inertia coupled with thread drive resulting in superior extremely constant speed. Low grip, slip coupling and let the huge mass in rotation do stabilize itself.
I mean - it works pretty well with our planet (and a few trillion other planets too.... yes, I know - there is no stylus drag on terra..... and it is a rotation in open space = vacuum) - why shouldn't it work with our turntables??
But again - you can not do it cheap.......... huge mass platter ( = expensive), very strong yet high quality bearing to handle huge mass platter (= expensive.....), high quality motor (good capstan - for instance...) (= fairly expensive again).
Not to speak about suspending the combined high mass with super low frequency from building resonance...... |
Dertonarm, I completely agree with you that the job of a turntable motor is only to bring the platter up to speed and then keep it from slowing down. Where I disagree is that platter mass alone is the the cure all for speed stability. A large platter mass does not negate the importance of motor quality or the quality of the drive mechanism.
In this thread there is a lot of discussion about physics. Of course what is happening in a turntable is about physics. But I posit that good turntable design cannot be purely about physics. There are several reasons that this is the case:
1) Nobody fully understands exactly what the physics are. There are a lot of very subtle things going on in a turntable that to date are not fully explained. There are plenty of theories and opinions, but not a lot of facts.
2) Good turntable design is all about producing good sound. Unless the relationship between sound and physics is fully understood then physics alone cannot be an effective method for designing a good sounding turntable. Harmonic distortion in an amplifier is physics. But building an amp with super low distortion often does not produce good sound.
3) Design is also about compromises. There are compromises to control costs that apply to any turntable design commercial or otherwise. A good designer will make the compromises that deliver the best value for the money and effort expended. In addition to cost compromises there are compromises related to balancing of conflicting technical goals. Coupling vs isolation, damping vs rigidity, light vs massive. Focusing on only one objective usually delivers poor results.
4) Like it or not good sound reproduction is a subjective pursuit. There is no such thing as an ultimate sound system nor is there or will there be an ultimate turntable. Everybody has their own set of musical priorities and no design will be a fit for everyone.
Back to platter mass I have done a lot of experimenting with various platters. I find that to my ears heavier platters do sound notably better. I also have found that a heavier platter makes that quality of the motor and drive system less critical. But even with a 70 pound platter subtle changes like belt material and even the motor pulley composition are still easily heard and are musically significant. Less subtle changes like rim or direct drive are even more obvious. |
Dear Dertonarm: I agree with you on your TT approach. IMHO this is a " road " to follow but IMHO it is not the " only and best " road. There are other examples speially on DD TT designs and certainly there are other " roads " in the brain of TT designers that they are not try it yet.
I agree too with Teres that physics tell us part of the whole " history " but there are several factors that affect and change what we are hearing it does not matters if the physics is on target, of course that everything the same a TT or any audio item that achieve a scientific approach is a better one and has to perform in better way too.
IMHO I think that are many " things " that till today no one already made a in deep research to find in a scientific way the. why's, where's and how's on each single TT design.
I know this because is something that I'm learning through our self tonearm design, where I'm " discovering " things that I never imagine can/could affect to quality performance.
Well, IMHO that happen too with TT's where scientific rules/law can't give us all the answers ( relationship factors ). Of course that if someone makes the research can/could have scientific answers but maybe to find out all those answers he will need not only know-how but a lot of time,money and common sense.
I like you and almost all people that cares about top quality performane/designs hate compromises/trade-offs but unfortunately these ones exist and the best each one of us can do is try to choose the " best " overall ones: such is life!
Regards and enjoy the music.
Raul. |
Yes, aramid fiber: http://scientificsonline.com/product.asp?pn=3034863&bhcd2=1232817787
Raul. |
Dear Teres, dear Raul, I guess we all agree in most aspects regarding the main topics / issues of designing a turntable.
I just have a very different threshold for "compromise". However I would like to answer Teres's 4 points first and in order.
I will speak very frankly here, as I just do not want to waste time and words.
1) Well - the physical phenomenons regarding the turntable CAN and ARE fully understood. Unfortunately and apparently not by the majority of turntable designers.
This is NOT all that difficult.
Unfortunately there are a lot of ill-founded theories and nice opinions around - right, but there are also the facts.
It is a fairly simple model consisting of two parts linked in one moving mass.
We have a rotating mass (the platter), that has to been kept on constant speed. The speed vector is provided by an external source (the motor ....whatever motor) the imperfections of that source (vibrations, unconstant speed) shall not be transmitted to the moving mass. This is one part of the whole system.
The second part is the act of extracting the musical information from the record groove. This act is a long line of different (both in amplitude and frequency) mechanical impulses transmitted into the record and into the rotating platter (the moving mass in motion = part one of the whole system). These mechanical impulses (which are a direct by-product of the stylus extracting the information from the modulated groove) depend on the VTF and the compliance of the cantilever (a FR-7 with low compliance and 2.6 gr VTF will transmit much more energy into the vinyl compared to a Shure V15 mk5 or similar (to name two extremes) while running through the groove and de-modulating the engraved information).
However the moving mass - the rotating platter - is therefor "threadened" by mechnaical vibrations from 2 different sources and (maybe - if anything like direct coupled) variation in speed from its external source of speed.
How to solve problem no. 1 (source of speed = motor) was discussed by me the last 2 days and is so far the only suitable solution if you want to use a motor (or multiple which is NOT a good idea...) at all.
One major point needs to be mentioned here which was so far not brought up: - of course the bearing of ANY turntable trying to bring out anything near the best possible must be TOTALLY free of any force in horizontal direction.
In other words - free of any force vector.
In plain words - there MUST be a counterpoint creating the very same force as the belt, thread, string etc. from the exact opposite direction and thus elimination that force to total zero.
Before this is not done, we do not need to talk at all about variations in speed, stylus drag, etc.
A direct drive doesn't have that problem of course.
Due to the fact that the act of playing a record does indeed brings the record into vibrations we need a heavy platter ( thats why heavy platters - if of any quality - ALWAYS do provide more substantial sonic information in both frequency extremes).
This platter must be - seen as a body - as insensible to vibration as possible. Consequently we are leaving the shape of a flat disc and platter and strive (if possible ....) towards a "round" cubus or (theoretical ideal) ball. To further increase the insensibility to vibrations other than shape is creating a compound "platter" made of materials of very different resonance behaviour
These are basic fundamental physics and nothing special.
The higher the rotating mass, less and less energy will be transmitted ino the platter.
If teh record is clamped firmly to the platter we (in an ideal situation...for which we can strive...) see the records mass being part of the platters mass. Thus less and less information will be dulled and smeared by a vibrating record (as Kirkus will agree, this is very similar model to a woofer working in a rather light and resonant wooden cabinet compared to mounting it in a stone wall - we both know that the dynamic, detail and clarity in impulse is dramatically different in these two mountings. It should be clear why.) and the pureness of information is greatly enhenced.
The point of suspension from outside mechanical resonance (building resonance) was discussed earlier and the solution is simple and can be obtained as a lug-and-play solution from suppliers already mentioned.
2) A turntable does not provide good sound.
A turntable has to had no sound at all. As above stated - all sound and music (should...) come from the LP itself. All the turntable can do is not ruin it. A good turntable is a dead turntable (as regarding sensibility to vibration and inner resonance). There is no such thing as a "good sounding turntable" or a turntable with "emotion (aside from its outlooks...)" or with "rythmic drive".
I mean these turntables may sound "good" and give the impressions of the above mentioned sonic features.
But they only allow these positive features to unfold.
They are in the record.
The other TT's just destroy and dull them in one way or another to more or less extend.
3) Nowhere is the relation between "good sound" and pure physic as easy and as direct as in the turntable.
I will always agree that there are tastes and many different ways to reach (Rome...??) excellent sonic results in speaker design, amplifiers and cartridges (I am less generous with tonearms.....) - and yes, we do indeed NEED distortion in amplifiers (2nd harmonic order..... only.).
No so in turntables.
Its all physics here - no mystery, no genius, no secrect, no ideology.
And again - if we are talking designing a turntable as a "product" for a "market" with "value for money".
Well, - than this discussion is futile from the very beginning.
A turntable very clos eto perfection CAN and WILL be build.
But it will NEVER qualify for a commercial product.
We do not need to compromise because the turntable is so difficult to build.
We need to compromise to make it to a "product".
Because here some people must have their financial share.
The product is the compromise - the compromise is not nessecary per se.
4) A turntable does not sound.
It allows information to be extracted without alternation - or it fails in some parts or many.
Allowing some parts and smearing and dulling others results in a "sonic signature".
All other parts of the audio chain do indeed have sonic individualities - cartridges, cables, amplifiers, speakers. All these are either elctrical devices or transmitters between the mechanical and electrical world (cartridge and speakers).
Not so for tonearms and turntables.
They are purely mechanical devices.
And we can make them closer to perfection as any other part of the audio chain.
We just have to be consequent and dare.
As for the perfect turntable - in the words of your new president: .... yes we can.....
I totally agree with you that the high mass platter does make the motor / belt / thread less critical.
But if you combine a super high quality motor with excellent power-supply with a really heavy platter and superb bearing and drive counterpoint - then we getting close in bring part one of the system close to perfection.
This is very significant regarding a vibration and force free system - and thus - after all, significant for musicality. |
There are some good ideas: BUT super high quality motor - the Designer has to know this part - he has to know how to use it - he knows, it makes his product more expensive excellent power-supply - see above really heavy platter - the Designer has to know: this alone is not enough - he has to know how to use it - he knows, it makes his product more expensive superb bearing - too expensive superb drive counterpoint - well, you know now: expensive What is the most hated word today? I think: expensive The customer would probably pay the price, but he pays it also, when a "Test review" is great (whatever this means) or when his wife says "Great, I like it" Most don't need more. Or? A real audiophile lives in pain or is Single :) |
Dertonarm, You have written that there should be no force on the bearing in the horizontal plane, and elsewhere you have written that use of more than a single motor is a no-no. (I agree in both cases.) But how would you achieve the former goal in view of the latter principle? |
Yep, expensive is the hated word for the day. Expensive applies to both commercial and one off, all out assaults. It's just that the threshold for a one off can be much higher. Maybe a solid gold platter would sound really good...
For me expensive mostly relates to time. There are a lot of ideas that have merit. But it is not possible to experiment with all of them. I am sure that I have discarded some good ideas because I didn't have enough time. Part of the art of design is guessing the most profitable ideas to explore. Nobody gets them all right, but one of the important skills in this endeavor is the intuition to get it right more often than not. |
Fascinating stuff . . . great thread (pun intended).
I will admit that I'm having a conceptual problem with the whole "controlled slippage" approach to filtering the motor vibrations from the platter. I can see how it would work brilliantly if all the conditions were carefully balanced . . . it just seems really inconsistent in terms of day-to-day usage, and likely to require very frequent tune-ups at least in terms the thread tension. But I will admit that I am comparatively ignorant of the real-world characteristics of these actual materials in this application.
Just a couple thoughts on the drive-system subject - first, how much data is available on the characteristics of the rotational vibration produced by the motors themselves? It seems to me that the relative strength and spectrum of this energy would be of paramount importance to determining the amount of slippage, the tensile flexibility of the belt or thread, and the necessary mass of the platter (and inertial flywheel device). Second, there is actually one more slippage mechanism -- that between the rotating magnetic force vector produced by the motor's stator, and the speed of the armature. It would seem that it's the interaction of these two time constants (or three if there's an inertial flywheel thingey) that ultimately determine how effective the motor/platter isolation can be.
Also, Dertonarm brings up the point of clamping and the record/platter interface, and I agree that it's undeniable that the platter must be of sufficient mass to effectively sink the vibrational energy of the record. But as far as the proper way to make the record-platter interface, that's another issue. There seem to be obvious drawbacks with clamping (tolerances in record dimensions, flexibilty, and condition), vacuum hold-down (complexity, noise and reverse-side dirt-bonding), and mere gravity (poor coupling). I confess that I don't really have an opinion as to what the "ultimate" solution has to be . . . maybe we just play lacquers! Issue solved! :) |
*** Well - the physical phenomenons regarding the turntable CAN and ARE fully understood. Unfortunately and apparently not by the majority of turntable designers. ***
Some of the phenomenons are well understood but many are not. Please explain why pulley material would be audible when used with a 70 lbs. platter. I don't have a clue what physics are involved for this case. I also am quite doubtful that even with the best equipment that this effect could be measured. I am not suggesting that this is magic. Something logical and scientific is going on, I just don't know what it is. I am sure that plenty of folks can come up with theories about why, but theories are not that same as really understanding the physics.
Oh, and yes this is a real effect that many folks have heard. Please lets not get into the subjective vs objective debates... |
Please explain why pulley material would be audible when used with a 70 lbs. platter. I don't have a clue what physics are involved for this case. Well, assuming that this is a thread-drive system with "controlled slippage", and assuming that you're talking about the motor pulley . . . . the first thing to look at would be the effect of the pulley material on the coefficient of friction on the belt material, both in terms of the material itself, and the resulting surface finish from a given machining process. Second, looking at some pulley designs (again using the Micro RY-5000 for reference) I'd guess that it *could* exhibit different resonant characteristics when made of different materials. And of course, if changing the pulley material changes its mass . . . But the effects of these criteria are going to be highly dependent on the actual vibrational energy coming from the motor in the first place. And when they reach the platter . . . just because it weighs 70 lbs doesn't mean that it doesn't resonate, and that vibrational energy can't move through it. And yes, this is all speculation . . . but from speculation comes hypothesis (not theory) . . . which is generally the first step in good science. As Raul pointed out, it's not that basic Newtonian physics doesn't apply, it's just a matter of having the time, money, and common sense to find out how. |
While testing different belt materials (DIY belts) I was quite amazed at the variety of achievable effects it had on the sound reproduction and impact this part of turntable setup had on sound. The differences are obvious and no golden ear required to hear that phenomenon. However, I would not stress the issue of why or what gives - you can not measure passion for music, can you? If the formula works, great. If it works in the ears of many, that is truly, truly magical. Why, because we are this funny group of people that tends to criticize music for locking musicality. To bad we stress and debate over silly rather then just listen. I am sure we all have an opinion of what others should buy or listen. Well, maybe it is time to reevaluate our own so call "reference" and get off the high horse. I've heard my share of so called "reference" setups by individuals which know it all.
I am still dizzy.
I agree with Teres - there is more to it then theory.
.....and enjoy the music
Mariusz |
Dear Mrjstark, dear Teres, if there is more then theory, then we are either in mysticque or religious grounds.
Different belts having different (negative and positive) effects on the bearing an dteh rotating mass system and on the transmission of vibrations is certainly no mystery nor unexplained by sience. |
Dear Lewm, a no force belt/thread/string driven bearing is done this way: picture the motor left of the platter. On the right side - same distance as the motor to the bearing - is a 2nd spindle (or easier: motor without active force) which mirrors the position of the drive motor. Here the belt/thread/string finds a 2nd pulley equal to the one on the motor. The spindle of this "counter device" should be same as teh motor sindle and all its moving parts shall be equal dimension and material.
Correctly done, there is now no resulting force anymore on the bearing in horizontal / lateral plane/dimension. The force of driving has 2 equal vectors now which do give which do zero each other regarding their effect on the bearing as they do go in opposite directions. |
Dear Kirkus, the "controlled slippage" is tricky to set-up, but if used with the "right" (= close to zero elasticity) thread it is very durable and does not request to be re-adjusted.
The drive-system is - as always - a matter of quality in the selected parts. I still do favour using any of the big Studer 800 capstan motors as drive motor for a "good" turntable. These capstans are expensive -yes. They require some pretty expensive periphery too - yes. But they are a totally different league.
These capstans are at work since the 1960ies in almost all great recording studios and a majority of all music recorded between the late 1960ies and early 1980ies (and beyond...) were recorded with these capstans being a direct and very paramount part of the big tape recorders.
Use one of these and give it the regulator circuit is needs and 98% of all problems with other motors and drives are vanished. Motor-born vibrations are minimized too.
And yes - it will cost you about $2000 alone in parts.
Quality NEVER comes cheap.
As for the clamping platter record interface. I do have the solution for that problem at hand. It however is rather expensive and labour intensive again. I do not think it makes sense to unfold it here.
The discussion about again too expensive and not suitable for a commercial product and crompromise etc. will just go on and on. |
In general we shoul decide, whether the main subject is how to design a turntable as a commercial product, or how to design a turntable which tries to reach the limits of playback possibilities.
I must admit that it is rather depressing for me to read in these posts so frequently that "this gets too expensive"....."have to made trade-offs".........."well-choosen compromise"........ "bring to market"........"commercial product".
This all sounds like the usual political paraphrases.
As was mentioned before - if we do not demand and strive for the best possible (an audio industry will tell us it is the "best possible" anyway every 4-6 months...) - we will only get what we have got so far:
......mediocrity......... |
Time to add something to the physics discussion here: if there is more then theory, then we are either in mysticque or religious grounds. I would like to clarify this a little more since there is a lot of confusion on words, especially on the terms physics and theory. There are several reasons that a theoretical prediction doesn't agree with praxis (and none of the reason invalidates the theory or physics in general). Without going into too much technical detail: - First of all physics does capture everything in the world and the physical laws certainly apply completely to turntable design or to the electrical processing of the signal for that matter. - The real problem is, we are dealing with complex systems: Yes, Newton'sche Mechanic describes the basic mechanical motional aspects of a turntable completely. And things like vibration transfer in the platter, tonearm, etc. are covered by solid-state physics. However, most of the equations one ends up with when describing a system completely is far to complex to be simulated on a computer. - For example, we could describe every microscopic particle and its motion in the turntable; the problem is there are more than 10^25 particles in a turntable; i.e. 10^25 coupled nonlinear equations. With our standard computers we would have to wait a few thousand years for the computation to finish. - Thus certain approximations and assumptions are generally applied which simplify the equations and make it possible to calculate the system behavior. Most of the times this gives a good enough "picture" of the system behavior, but quite often calculations and predictions do not capture every detail and minor aspect ton include these details we would have to revisit our assumption, include less approximations and more terms in our description which in turn makes things complicated to calculate and predict again. - As a result, practical trial and error is often a lot easier which is why some (like Teres and Mjstark) would probably refer to turntable design as art rather than science. Now, basic simplified engineering equations may not describe the results of our excellent practical outcomes, but the underlying physics is still accurate, but just too complex for a full calculation and prediction. - A lot of the things we are talking about here (belt creep or slippage, effect of different belts, different pulleys, stylus drag, etc.) are higher order corrections that are difficult to model, but easy to try out in praxis. Even the Apollo missions rely on practical trial and error in the development stage as well as practical tests in addition to basic physical principles. - Finally, some semantics: There is a subtle distinction between the terms "Theory" and "Hypothesis".The terms are often used interchangeably which is incorrect. Scientifically there is a big difference (see for example the Wiki) - Just because a system is complex and difficult to predict it does not necessitate religion or mysticism. Similarly, just because we don't measure an effect, but we hear a difference doesn't mean the physics is wrong; it just means our approximations and theoretical assumptions are wrong and/or we measured the wrong things. Bottomline, we could probably achieve a lot more with a careful scientific description of turntable design (as Dertonarm instigates), the whole audio system, and even human hearing. But in praxis, trial and error and careful listening is still a lot easier and effective in achieving better results (which strengthens Teres point). This is just the perspective of a physicist of course ;) Rene |
Dear Restock, a superb post - thank you very much! I would like to mention however that I do not see me in some kind of opposition regarding Teres, Raul or any other of the well-respected contributors to this thread.
I just wanted to clarify the point that this particular part of the audio chain is - besides the tonearm... - the most simple to handle. Here we do only have to work with mechanics. The other components are either electrical or machanic-electrical transducers (much more complex ). Taste, personal preferences and opinion, room interaction and matching impedances and many more do have enough room in the development ofspeakers, cartridges and amplifiers. and they are NEEDED there.
But not in TT design.
Yes, -in the end everything in music in subjective.
But the very best turntable possible will have absolutely no sound signature of itself. It will just allow the maximum in clear detailed information to be extracted from ANY given cartridge/tonearm combination.
The turntable is nothing more than the enviroment, the basic floor on which the analog-playback starts.
But if we relay on hearing/listening in turntable conception and design, we automatically imply that the turntable is the weakest part already and per se in the particular audio-system used to determine its quality.
We all see the problem: to judge the performance of a turntable design by sonic performance, we would need an audio-system were all the other parts are "better" than the TT under question.
But most likely we will design a turntable which "sonic signature" will mask certain flaws of the audio chain used to develop the TT.
It will be designed to compensate flaws of the evaluation system used to develop it.
This dilemma is omnipresent in audio of course. However in the turntable we have for once the opportunity to design on pure physical, mechanical parameters and facts.
I do see a clear and straight road here.
It may be long road and the journey may take a lot of effort in many ways.
But the goal is that mountain clearly visible in the distance - not the next inn or diner which will lure us with comfort (=compromise) by the first signs of effort or weariness.
Once entering the door of that inn and sit down at the table you will not carry on on that journey. The day is done and teh job as well. You went awhile and has reached new ground. Its o.k.
Thats what happens all too often.
We should be strong enough to walk through the night.
We should not discard the opportunity to reach the mountains that easy.
As is so pathetic written on the memorial for the american pioneers (hope I remember is right... in brackets are my synonyms....):
"the cowards didn't start (CD-player from Radioshack....), the weak died on the way (settle happily with current "state of the art products".....) only the strongest reached the mountains - they were the pioneers (.....and probably died exhausted, wounded and torn by life - but o.k., if they did what they wanted and reached what they dreamed of)".
Well, sounds like a pathetic political speech for fortify indurance in the sight of worldwide financial crisis doesn't it ??
Did I mention this is about turntable design....? |
I think one can some up the problems very simply, but I'm probably just restating what has already been posted here. As I see it the problem is not of design and proper application of physics. The real, true problem is integration. This is true of any complex system, not just with turntables.
You can design and plot and plan all you want. There will still be some compromise or component that you have to go to the shelf for. And then you are constrained by the operation of that component. That is when "feel" takes over, right or wrong. This is true for any complex system in the real world. This is the realm of practical experience and personal preference. This is also the realm of great breakthroughs and great failures. |
Dear Mrjstark, if you ever should try different belt materials on a force free lateral (horizontal) bearing, you will observe that the noteable differences in sound will be much less compared with the differences noted in the "standard" (=one motor - no counter spindle) set-up.
Why do we hear so huge difference (I will certainly not deny the fact that there are audible differences with various belt / thread materials and other tweaks in turntable design (mats, clamps, isolator feets, spikes, platforms etc.)) even in state of the art turntables ??
Because these turntables are NOT finished "products" (seen in the sense of a market or as a non-commercial design).
Most likely the designers were under time-pressure and/or seeing the end of the budget and thus need to bring the TT "on the market now".
A "finished" turntable (or any other really "finished" product....) will either show no positive differences with various tweaks or they aren't possible at all due to a design which takes all aspects into count and leave no room for our "add-on", "upgrade" or "tweak"-mentality.
You can't tweak a turntable with force-free bearing running with an aramide or dyneema thread. There is no better material possible so far.
You can't tweak a Minus-K 0.5 Hz suspension by putting spikes or cones underneath. It is already suspended in the best possible way.
We do hear so many differences with so little changes in so small parts because the turntable is so weak.
Because there is so much room for further improvement.
Because we stop too soon.
Because we are satisfied with so little. |
Dear Dan_Ed, agreed on the large scale.
And yes, - there will always be "some" (I hardly can write the word...) "compromise".
However NOT SO FAST.
I do get the impression that most designers are seeking for the nearest possible compromise.
That the real goal for most is: finding the best (read: cheapest and nearest....) compromise as fast as possible.
I have no problem with a compromise when there is NO OTHER CHOICE possible. That is early enough.
And frankly - that point will never be reached in turntable design.
We should get real, we are talking about turntables - not about space shuttles, Formula 1 racing cars, atomic submarines or the hubble telescope.
A turntable - a simple mechanical machine....... sorry, I can not see any need for compromise here. And we do not need back-up by the Pentagon or Northorp Aviation to be able to design and build a near perfect turntable. |
Ah, so now we are cutting to the chase.
In the real world, there are always compromises. Even the equations that we use to model real world behavior have compromises built in. One can certainly chose which to address, but on cannot avoid accepting compromise in one way or another. Even if one is not aware of the compromise(s) at the time. That is the leap from paper to reality. EVERY system, mechanical or biological or whatever, in the universe has built in compromises. It is unavoidable. So I propose that we drop the pretense that any system can built without compromises.
I agree that all turntable designers/manufacturers will make decisions based on commercial interests. Absolutely. They want to be able to sell what they have made. However, even those who profess to have spared no expense and made no compromises are deluding themselves, IMO. Look closer, I say to them. Compromises are there. |
