Direct Drive vs. Idler Drive vs. Belt drive

Dear @mikelavigne  : from several of your post before in this thread it's clear your " preference " for the Saskia/CSPort over the NVS and this is ( again. ) not under questioning in any way.

Exist something that in some ways " worry " me and I will try to explain about:

Wave Kinetics main works/business/knowledge is about  control vibration systems:

https://wavekinetics.com/#why

https://wavekinetics.com/vibration/

https://wavekinetics.com/the-truth/?doing_wp_cron=1603815532.3626220226287841796875

@jtinn is the owner and decided to design and manufacturer your NVS Reference TT because he is a music lover an an audiophile.

it's from there where comes:

https://wavekinetics.com/products/nvs-reference/

with out diminish in any way the Saskia/CSPort design and high quality levels in that excecution designs and what just does not makes " click " in my brain is what you, some way or the other posted several times,:

"  regarding the CS Port LFT1 it has considerable mass (both plinth and platter) and an air film suspension and air bearing (low flow, low pressure) all contributing to low noise.

the Saskia has a 180 pound plinth + 40 pound platter and built in suspension. all that mass in all the right places does help to make it easily the quietest idler i’ve heard. "

" low noise " and quietest ", DD motors not only are way quietes but with a very high signal to noise ratio as the 96dbs of the SP10MK3 or the over 100dbs figure in the latest Rockport Sirius you owned and the NVS is a DD drive motor and today motors are just excellent against any other design but additional to that WK has a deep knowledge levels in something that's way critical in any TT, TT platter and TT arm board named: VIBRATIONS, developed internal resonances and out side/external isolation.

In 2014 Tony posted about TT speed control::

"  I believe that listening is the final test in evaluating a system; but I also believe in
using measurement tools to reduce time and trials in getting to that final
listening test. I put a lot of stock into Dr. Feickert's iPhone app. Use it as a
relative tool. I think the frequency measurements are dead on because the app
uses the iPhone's internal clock. ""



Saskia goes for mass about as CSPort and nothing wrong with that the more expensive TT ( over 600K dollars. ) weigths around 300 kg and its specs are poor as the CSPort I don't know about the Saskia numbers and yes I know what other gentlemans will say: numbers are not important but but the quality of whaT we are listening but when we are talking of this kind of quality levels numbers(specs/ovjective is way important and at least at the same level of our subjective " feelings ".

I want to think that the Saskia/CSPort were designed taking in count ( as you said in one of your last posts. ) that platter weigth/material/bearing and the rigth motor torque for that.
In 2014 Tony posted on that matters:

""  The motor and platter are part of a system. Any one of the two out of balance results in poor performance  """

Saskia owner posted about:

"  I like high mass platters, but where the mass is located is critical, in my opinion. If properly done, the platter can be an extremely important component toward reaching the goal of optimal system inertia. "



We can ask: why Saskia over 200kg of " slate " and not a different build material or blend materials and why not 150Kg.? same for the CSPort. NVS is expert about it's his main work/knowledge. Again I'm not diminish the excellent work by Saskia/CSPort.

Mike, for a moment please forgeret of your preference about and take all those facts in your mind and tell me if makes sense to you.

Speed controller makes the difference for your preference? because that's what is in your whole words/posts.

You said too and this is the second time in the thread:

""  there are pressings where my active shelf takes the NVS to another level of precision. ""

If you can I would like to know what really means your statement and if you can mention recordings where you experienced that characteristic and I understand that even that you are not biased in the same way that with the other TT designs for the NVS.

And please sorry to disturb you again and again and thank's for your patience.


R:

Btw, you posted:

""  Therefore, fine vibration generated by servo control can not be measured by the measuring instrument, it depends on the human ear. ""

Everything can be measured today no matters what and in 2014 a gentleman posted about:

"" Richard, very easy to read with a frequency counter and test record with steady tone. In a fraction of a second I've seen servos change 30 hz when playing a 2150 hertz tone ""


Today tools and knowledge levels already improved over 2014.

Dear @mikelavigne : With servo or optical or whatever speed controller we use it happens exactly the same:

" but at the micro level, if it rotates or becomes faster, it detects it and slows it, and repeats the operation to make it faster if it gets slower. "

The TT platter rotation speed is affected by to many circumstances not only if the motor is DC or AC one and it does not matters the drive kind of design TT has.

Some of those circumstances that affects speed stability in the extremely short period of time are: stylus drag at high velocity LP recorded grooves and this could happens any time at any LP surface positions, electrical power source, even some one detected that static developed can impair the function of the speed controllers by million of a second time periods, non perfect flat leveled TT that could affects the platter bearing stability, as the cartridge stylus tip the TT bearing goes degrading through the time, belt degradation, pulleys suffers of that degradation too as the ID internal mechanical parts, even the speed controller has a time degradation too.
All those circumstances and many others makes a TT imperfect item suceptible for the speed controller goes in/out trying that the speed stays stable in the very short time.

That’s why I ask for mosin/jtinn or any other TT manufacturer in this thread but even if no one can comes the reality is that you can’t detect it those extremely fast speed rectifications because you can’t detect those speed rectifications that were do it for the cutting lathe through his speed servo controllers. The cutting lathe Technics motor ( SP02. ) use the same servo than the SP10MK3 ! !

But all those cutting lathe motors are way vintage designs and even that old speed controllers designs you can’t detect it those servos in any of your LPs played trhough the Saskia or CSPort ! !

You can stay entitled to your way of thinking but it’s only that " a way of thinking " a subjective way and not a true fact/objective because you can’t hear it in any TT drive design at any price levels.

Now, it’s not here if you are rigth or wrong but the matters is if really exist what you think or just does not exist as I support.

I know very well @lewm and he owns ID and DD different TTs and that I remember he never posted that can detect a problem about but it’s not the only audiophile because there is nothing that proves that non-existent symptom. Other gentleman is @cleeds and I can name you several more including the gentleman you know very well that’s an AS BD all metal design distributor or manufacturer ( I’m not sure about. ), the one I linked the wbf here.

Mike, with all respect: as a cartridge or speakers or electronics any TT design is the sum of its parts inside the whole design and you are taking only one part/characteristic/parameter of that whole design where things are that all TT designs, one way or the other, shares in between no matters what.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

Dear @mikelavigne and frieds: Mike,with all respect servos per sé are not a devil it does not matters where you use it. For your coments in this thread seems to me that that word over distress you and with out any single reason/facts true3 facts or measured ones. You have a " feeling " about when you said:

"" i view both the Saskia and CS Port as having the most steady tonal solidity of any turntable i have heard. the NVS and EMT are also very fine at that ’steady’ and ’solid’ type sound. only that the Saskia and CS Port are degrees more grainless and liquid, as well and greater tonal shading and density ""

that’s what you like it and nothing wrong against that but the Saskia and CS Port TTs are both way different whole designs against the @jtinn great NVS DD design, even the CS Port comes with its dedicated LT tonearm.
Mike there is no way that those 3 different TT designs can sounds almost the same. Again that " degrees more gainless and liquid " is what you prefer.

Now, let me explain something in that overall rectification speed controllers subject including the servo " devil ":

exis different kind of servo designs using different " tools "/technologies to do it: cristal quartz look ( that normally we can disengage. ) is one of them and one of the technique used in the vintage DD TT and still today works really fine, there are servos that sense the speed over " thousands " times at each TT rpm and are " there " only when is need it a speed rectification even exist bi-directional servos as in JVC, Yamaha or Denon TTs.

Other than TTs subwoofers use servos and as the now defunct Velodyne they did it through an patented accelerometer that sense the wooffer movements over 80K times each second to mantain the THD lower than 0.5% at 20hz at 120db on SPL. Your speakers subs has to have some kind of controller to its low bass range stays with low distortion levels, you can’t avoid it.

This is what the motor designer of the Saskia posted:

https://db.audioasylum.com/mhtml/m.html?forum=vinyl&n=1081734&highlight=saskia&r=&se...

This was posted by Sakia manufacturer:

https://db.audioasylum.com/mhtml/m.html?forum=vinyl&n=1117513&highlight=saskia&r=&se...


Mike, you said:

"" the Saskia does have an optical reader installed ...."

I can think that that optical reader is to make speed rectification/corrections when is need it. Same function as any servo speed controller.
If you can detect the servo operation then you must detect this kind of rectification no matters what and if you don’t did it then both the servo and the optical controllers has no real/true intrusion in what any one ( including you. ) can listen or that can say exist an " intrusion " because in both cases exist a " change to the TT speed "/a correction to.


In 2014 @richardkrebs posted about that optical controller type:


""" Dougdeacon said...

"No strobe (Timeline or otherwise) operates in short enough increments of time to detect micro-/pico-/nano-second variations. Knowing that a TT is speed stable across a time span of minutes tells us nothing about how stable or unstable it may be across a few thousandths or millionths of a second. Such short-period variations are just as audible and musically important, arguably more so."

Brilliant. This is so true.

Tonywinsc also touched on the same point.

IMO it is the reduction of these tiny speed changes that is one key to a TTs performance. Do we have a way to objectively measure this? Maybe, with some of the new optical speed sensors capable of measuring greater than 1x10^6 counts per rev, but I sure know that we can hear it. """




In the other side and about the CS Port BD TT and only looking at its specs I can say that are really poor against today/vintage top standards in that regards. These are those specs and certainly you must listen to it:

"" Crystal follower non-feedback motor drive

XFD method.

Rotation transmission method Yarn drive (four-wire aramid fiber).
Drive motor DC coreless low-noise motor
Rotation speed33 1/3 ・ 45rpm (with switch selection and rotation fine adjustment)
Rotational speed accuracy±0.3%
Wow and flutter:

Wow 0.2%

Flutter 0.04% or less """

I already posted that I can’t detect any disturbances in what I listened or listen through Denon and Technics top models due to its servo speed controllers.

I can’t detect either any " intrusion " by speed motor drive corrections in my BD Acoustic Signature unit where I use as a belt either: aramid fiber thread or silk thread. Btw, I neither detect it speed controller intrusion with my Micro Seiki TT.

I have to say that I never had in my system an ID TT.

I insist in this " devil " TT subject because as I posted before the servo controllers are the ones used in all recording cutting lathe DD motors and no one can detect till today any trouble because of that in any of his LPs.

For me all those means exist no true problems about and certainly no objective facts.

I know that for all audiophiles and everywhere, including you, could be really a learning " sessions " that both: @mosin and @jtinn be so kindness to chime about because the issue is way critical.

Gentlemans both of you thank’s in advance and appreciated.

Regards and enjoy the MUSIC NOT DISTORTIONS,

R.

Dear @cleeds  : @mikelavigne  was refering to the BD/ID model TTs he owns today: Saskia and Csport against the excellent DD @jtinn  NVS Refrence TT he owns too.

I really don't know the kind of motors that uses the Saskia and Csport units.

R.

Dear friends : I want to return to that " supposed "/hipothetic DD servo " problem and I want to do it because @mikelavigne  was very emphatic about in this thread.

This what Mike posted:

"""   when we consider belts, idlers, and direct drive........2 of those have the choice of no servo’s.

i’ve owned a number of top flight direct drive turntables; including the Rockport Sirius III, the SP-10 Mk2 and Mk3, and now the Wave Kinetics NVS for the last 9 years. taken singularly; none of those were obviously lacking in speed solidity and musical flow. but over these last 6-9 months, in direct side by side comparison to the Saskia model two idler, and the CS Port LFT1 Belt drive, neither of which have servo’s......this idea of the human ear hearing the musical cost of feedback is very real.

execution of an idler or belt to the degree to take full advantage of the lack of feedback is paramount, but when you do your ’ears’ will thank you.
but the separator turns out to be the lack of servo on the belt and idler. i’m drawn to those two emotionally more. now that i’ve lived with those i’m always conscious of that aspect of my NVS direct drive.  ""



and this my answer I posted to him:

https://forum.audiogon.com/discussions/direct-drive-vs-idler-drive-vs-belt-drive/post?postid=1952212...

He in very plite way as usual from himjust tell me he disagree totally with what I posted.


In what I posted in wbf things were that the gentleman ( that's an American Sound distributor ) posted there that the only DD he likes is the DP-100 that comes with servo control, this goes against his TT servo " repulsion. ).

Today no one can't prove that the servo control in DD TT develops a " problem " that we can hear, not even Mike can do it because he as the wbf gentleman can't listen that hiphotetic problem through their BD/ID units when all the LPs they and we are listening where cutted through DD motors that all were/are speed servo controled .
So any trouble about servos must be reflected in the LPs we listen to and this never happens or at least is what Mike shared when listening through his BD/ID units.

The information I shared in my last two posts were unknowledge by Mike when he posted about.

I don't know with all the evidence in the subject what he could think today and maybe could be interesting for all of us that he can be so gentle to share his opinion even if he could/would confirm what he already posted. Could you?, appreciated.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.



Btw, @alexberger in this thread posted:

""    Yes, the belt drive have advantage of very low noise.
BUT, when you listen an orchestra,on one hand you can listen a 10th violin separately and other small details, but on the other hand the rhythm and flow of music is broken by belt drive momentary speed fluctuations. I think the rhythm accuracy and flow of music is much more important than small details.  "

Way interesting too.

Dear @Dover : Agree but that does not means dissapears, only " less invasive ". problem is that we can’t know what that means exactly.

In the other side gentlemans ( other than ML. ) that own the Technics MK3 did not posted about " problem " with the servo. I owned the MK2 and never detect it against BD TT neither with my Denon’s and if I rememeber Halcro neither in that specific issue or even lew.

What I said is that what we can detect in a DD vs BD/ID TTs couldbe a " trouble " with other kind of DD designs characteristics and not because the servo.

R.

Dear friends: This is something I posted in wbf to a gentleman that was against servos in DD TT because he said that he can hear the damage that servos makes to what he listening through a DD turntables ( as the Technics SP10MK3 or Denon DP100 and the like. ) . Could be interesting to think a little about:

"""  But things are " critical " for say the least about your " entitled " against servos because the recording LP cutting machines uses DD non-coreless motors as the Technics Sp-02 on the Neumann or the servo controled ( as the Sp-02 ) Parker motor in the Lyrec lathes. In Scully lathes some gentlemans used the MK3 Technics motor. Altivar was other used motor and obviously its own Neumann one and even Denon.

So the LPs you listen was recorded with those servos ( not the bidirectional as Denon or JVC and not coreless motors as JVC, Yamaha or Kenwood. ) and even that that kind of " servo intrusion " especially in the low bass range you just can't be aware of it in the BD or idler drive TTs when that " servo intrusion " in case of exist must be appeared any time with any TT spin design, it comes ( according that exist that servo problem. ) rigth from the cutting lathe. So, You can´t be aware of it because just does not exist ( you are not aware of it in BD designs. ) or your room/system has not really and true high resolution. There are no other alternatives down there.

Measurements and pure common sense means that your " entitled " servo issue is a misunderstood that you posted and post " over and over through the years. ""

Then the LPs are pressed from the cutting lathes that used DD motors with servo control. So why many  audiophiles said that through BD/ID TTs the servo " intrusion " does not exist they do not be aware on it when all the LPs where pressed " using servo control motors?

Perhaps because what we listen and disturbs to some of us in DD TTs comes not really from the servo control but from other each model design characteristics and not because the servo control.

Maybe some of you can share a different point of view on that critical TT issue.


Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

Dear @thuchan  : In the world of audio nothing is perfect always exist trade-offs.

In belt drive TTs as in other TT kind of designs always exist trade-offs where the designer has to make his choices.

A single motor per sé has its intrisecal " problems " that can't be avoided and that like it or not affects the whole TT quality performance levels.
A second or third aditional motors only puts more " problems " for the quality level performance of that TT that any true advantage.

One of my belt drive TT's came with one motor it's the stock way on sale but you can add other two motors so I bougth a second motor and made my in deep evaluation overall process about.
At the begining my thoughts were that the second motor was an improvement ( maybe because I bougth it and spend additional money and I was waiting to appeared that " improvement ". ) after the evaluations over 3-4 weeks I took in count that was not a true improvement but only a diferent performance that in some ways degraded a little what I was listenong through it.

Yes, those vectors exist in theory but you can't really listen an improvement if you listening to it with no self biasing about. Our brain/attitude on any specific subject has a lot of influence and makes that we go a head with some " mistakes " or alternatives that really does not helps to improve quality performance only a different performance.

R.

Dear @spiritofmusic  : ""   I can't think of anyone trying out tts in a retail store and moving the same cart from one tt to the next..."""

me neither but when you own two different TT/tonearms you can make comparison of a cartridge performance with each of those TT/tonearms. 

According the ML room/system Agon pictures he mounted ( at least pictured. ) the same cartridge with today 2 different TT/tonearms.
Again, not at a retail store.

R.

Dear  @alexberger :  ""  It is weird that people on this forum are not familiar with EMT 950 and 948 DD turntables. .."""

not really, many of us are familiar with. Here exist several threads on the EMT, I participated on at least two of them. This is one of those several threads and before and after it exist more ( this is only an example. ):

https://forum.audiogon.com/discussions/emt-turntables-as-good-as-other-great-vintage-tt

the things are that you are almost new in Agon. An audio friend of mine works in a radio/tv big network  and he invited to a listenning session down there and ovbiously a " tour " around the company. The listening session was using one of the 10+ 950 TTs they used to and during the " trip " to the company installations they had only one SP-10MK2.

Btw, yes your friend is rigth, the SP10-2 sounds sterile. I owned 3 samples that I sold when my Denons outperformed with some easy to it. The Denon servo design makes the differences because the 10-2 specs are higher than the ones on Denon units but specs never says all. The MK3 is different but still with some trouble in the servo design.

Now and speaking of EMT, Technics and Denon the EMT and SP10 as the Denon 308 and DP100M were designed expressily for radio stations not for a home audio systems.
Latter on came the Technics MK3 and DP100 for home systems. 

R.

Dear @mikelavigne : """  these things are always degrees of success, trade-offs and compromises. again, anything mechanical can only approach perfection. ..."""

As you I think you own 3 different drive TTs where each one is  one of the best on its kind out there and due to the top quality level you are experienced with more than real compromises or trade-offs what exist is " only " just top quality performance but with different  " color " that as you said all are approaching perfection at levels you don't experienced before.

I'm sure that each of your TTs designers are really satisfied with the way the items performs.

R.

Dear @mikelavigne : Thank’s. Your first sentence was my own answer when/after I posted. It was obvious but I can’t seen before.

""" all three challenge my big Studer’s for musical rightness.. """

there is no best way to explain the top class all of those 3 TTs that are a true challenge for any medium.

You really have deep experience along your very high resolution room/set up that permits that even that top quality performance you are a little on the CS port BD design and something is down there this kind of drive because 0ver 90% of my LP listening sessions are through my BD TT and not my DD ones.

I remember you since you owned the Goldmud Reference and when you changed from the Sirius 3 to the NVS I knew that there were something really special and indeed was and is that way.

Good to see you again in this forum, always a pleasure to read your posts.

I know that you post often in WBF but I was banned from there, some people there with closed mind and I’m not to polite because that’s the way I’m.

Anyway, as always a learning sessions with you.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

Btw, the studio DD TT 308 you named has bi-directional servo. Very good vintage studio TT.

@mikelavigne  : After I posted the last one I followed thinking  about and I thought I had the answers but I followed thinking and rigth now I have more questions than answers between the kind of TT drive ( inlcuding the servo issue. ) and what I posted. I think that those no-answers came because I'm not " there " like you and that's where belongs the importance of your coments, maybe exist other " things " around that only you know it.
R.

Dear @mikelavigne : I can’t argue nothing in your answer post due that’s way coherent and make sense to me.

However I like to understand ( not only with what you are listening through your room/system but coming from some one else. ) what is really happening down there even that I’m not " there " but your posts speaks a lot but exist things that maybe words can’t explain thae way I need it.

Let me explain it in other way and please we can ( for the moment ) take off/out the TT drive issue and analize a little what can modulates the sound you are listening other that the recorded groove modulations because I think that those other very tiny modulations puts its own " color " that can or not makes subttle differences in between your 3 great TTs:

all the 3 TTs are building with different blend of materials at each different places inside the whole TT and the blend of those materials and depending were are used tends to resonate/vibrate under dynamic stage/when are spinning during play. Those kind of very tiny or micro resonances/vibrations are different ( example: at different frequency. ) in each one of 3 TTs.

Now, what happens when the cartridge start to track/ride the LP groove modulations inside that whole mechanical circuit ( of course that it’s too the lectrical side but it’s not the issue here. ) formed by: TT/tonearm/cartridge/LP?

As I said that circuit is a mechanical one and we can’t avoid the Newton Laws down there that lives down there one way or the other.

When the stylus start to ride the groove modulations that act develops many other tiny modulations as: feedback from the LP surface due to the friction of the stylus tip forces, the surface of the LP and due to that very high friction forces makes that exist too a feedback from the LP surface that is in touch with the platter or platter mat .
These are the first tiny developed modulations that goes mixed through the stylus/cantilever along the groove modulations ( the cartridge can’t make any difference between the groove modulations and the fedback modulations, just took it as it was the same. Is a very sensitive movements sensor. ).
That kind of feedback is followed by the cartridge body self feedback developed by the cantilever/stylus tracking and comes a new feedback movement that’s very fast transmitted to the cantilever and that same cartridge body feedback and through the top plate of the cartridge is transmitted to the tonearm headshel and starts to resonates in between ( this is totally independent of the resonance frequency in between the tonearm/cartridge and its compliance. ) and transmitted through the tonearm and then to the arm board but does not disappears because part of those kind of resonances/vibrations return through that arm board to the cantilever/stylus and mixed again with the true groove modulations.

Things do not finish here but I think you have the idea of what I try to explain about.

At the very high level of resolution that you are listening all those it matters ( at least for me ) because even that all 3 TTs are extremely well designed and excecuted and with the necessary overall damping ( that’s why the designers choosed materiasl and where to use it in the design. ) that each TT color exist and you are hearing it because no one can’t avoid it can’t makes that disappears from that mechanical circuit.

Normally those developed " modulations " affects the more to the bass range that at the same time it modulates ( color ) the other two frequency ranges. My common sense tells me that all those is happening but as you pointed out in your answer to me I can be wrong and I really appreciated your comments about even that what you are listening something magical for the first time in your life. I whish I can do that some time in the futura if God Gives me the life.

Thank’s in advance,
R.

Dear @mikelavigne  and friends: you say that in your 3 today TTs MUSIC flows and spin with speed stability that at least you can't detect.

I want to think that your TTs comparisons were made it using the same cartridge and at least in the NVS and Saskia with the same tonearm model.

The DD servo motor control always comes in any drive TT discusions and for the same characteristics that @richardkrebs  posted here but even he can't really detect that characteristic because he use DD TT.
I have first hand experiences with several DD TTs and BD TTs but not a first rate idlerdrive one. As Richard and you I can't detect any non-stable speed changes because the servo control.

So I think that even that in your post you make the observation that 2 of your TTs has no servos we can't say that the differences in quality listening levels are not because the servos.

So, from where came or comes those differences ( paramount. ) ?, you pointed out the excellence in all those 3 TTs quality excecution to its designs.

It's obvious that your room/system is fine tunned at any level of excellence we could imagine or even if we can't imagine it. No doubt about.

The MUSIC sound is developed by an extremely movement sensitive sensor anamed cartridge that pick up tiny/micro movements/resonances/vibrations/feedback and the like coming by inside the TT/tonearm/tonearm board/LP/cartridge body ( at least. ).

So it does not matters if air bearing or DD or idlerdrive all of them are " resonating " somewhere in different way ( using the same cartridge/tonearm. ) and the cartridge is taking that overall non damped resonances/vibrations/feedback or whatever you want and for me it's here from where comes all differences in between, at least the detectable ones.

Additional to that we have to take in count two critical subjects due that the Csport TT comes with a LT tonearm way different to the pivoted ones in the other two TTs under comparison and the Csport tonearm is seated outside the TT main plynth and this is a difference when we listen through a room/system with so very high resolution as yours ( @atmasphere can explain this in better way than me. He is against separate tonearm towers and in theory is rigth. ) and the tonearm internal wiring is different too.

So for me differences in between has a name ( at least between the NVS/Saskia. ) : overal damping levels and I mean it at each single link inside the TT/tonearm/cartridge chain. With the Csport exist more variables and we can't really say what is " happening " in reality: the " weigth " of those variables for the differences.


All in all the NVS and Saskia seems to me as a little better overall designs than the Csport even that this one has its own " merits ". Btw, something that disturbing me a little is its average/low specs but specs means " something " but certainly not all at all.

Well, I wish to own any one of your TTs.  ! !


Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

Dear @scar972 : As cleeds posted, first hand experiences is the solution.

In the other side please make your work and brose all the information here in this forum about. Exist " hundred " of threads in that same subject.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.