SP10 Mk II vs Mk III

Here's the thing. If you fire up your SP10 MkII while it is just sitting naked on a shelf, you will see that IT will "do a little dance" (altho I never saw one make a little love). It does a little dance because of Newton's 3rd Law of Motion, and because of the high torque generated at start up for which force there is an "equal and opposite" reaction, as Newton told us. The job of the plinth is to soak up that force and stabilize the system. After start-up, the torque needed to keep the speed stable will be much less, so Raul could argue that a high-mass plinth is not needed once the correct speed is attained. However, I think a well built plinth dissipates vibrational energy that can otherwise color the sound. However, there's no harm in trying Raul's idea.

I actually tried the naked approach before, about more than 10 years ago. I had a small piece of 3/4" particle board attached to the upper right hand corner of the stock chassis acting as a cantilevered armboard and that's it. The turntable was just sitting on the table by its belly with four stock small rubber pucks. It was pretty naked, think of a naked person wearing a right hand glove. I had an MMT arm at the time, I think.

It didn't sound all that hot because I remember later on the same arm was mounted on a McCurdy radio station metal frame type of plinth and sounded better than the previous set up. And my custom butcher block plinth also sounded better than the naked approach but I had a different arm so that comparison is probably not valid. I guess I can always try it again with a different tonearm, like one of my Audiocraft arms.

All I am saying is that I am not convinced no plinth is better than having plinth. Just from a pure physics stand point, the SP10 has so much damn torque that you would think you really need something massive to hold down the turntable to sink all that vibration. Didn't Mark Kelly tell us that Sansui experimented something like this about that return torque that's causing the turntable cabinet to color the sound? From my experience with the naked approach, the set up did have that typical Technics clinical sound so I would imagine having a massive plinth is the right approach to high torque DD turntable like the SP10. I am not sold on your approach but, hey, if it works for you, great, because that certainly saved you ton of money on plinth. But before I try the naked plinth thing again, I can't wait to mount the naked motor to a slab of slate!

Dear Albert: +++++ " making a comment like that with absolutely no foundation. " +++++

+++++ " How anyone can audition a system with everything..........and without your own version or "mod" of the table is beyond me. " +++++

+++++ " but when you post something so off the wall as you have, I begin to question your test methods .." +++++

I receive several emails on the subject since your post with different flavor opinions and I need to clarify on the subject trying to put a little more light on this " controversy ":

like I posted each one of us have ( sometimes ) similar, different and especial skills on " audio culture " ( each one audio learning curve ) where some of those especial differences comes on each one because we each one choose to " cultivate " in especial some audio areas that are more interesting to each one of us.

Well, I want to write some experiences ( even one that you live with me ) to show the skills I'm talking about:

been in San Diego with a very nice audio friends we were hearing differents Phonolinepreamps ( in at least two different audio systems. ) between them the Dartzeel and Esential 3160.
In a specific time/moment we take each one opinion on the quality performance of those Phonolinepreamps and I remember what I say on the Dartzeel : that both frequency extremes were not natural but manipulated on purpose to give the Dartzeel signature sound, this was/happen 3-4 months before the Dartzeel review on Stereophile where I confirm ( by the product measurements. ) exactly/precise what 3-4 months before was my opinion on what I heard in the Dartzeel that was surrounded ( in SD. ) of " unknow " audio items to me and where I was traveling around USA.
We discuss for hours our each one finding on what we heard there and I can say that we have very good time in that unforgetable friend's meeting.

in other trip in USA I visit to Steve Doobins and for that days I don't have almost no reference/know-how on the strain gauge cartridge/system that he own so I was not prepared of what I shall hear there.
My reaction was very fast: impressive just at the begining but after a few minutes and especialy on the highs and tonal balance I say Steve that I don't like it and I tell him that I think that the " trouble " for me was not on the cartridge but on the cartridge electronics.
Months latter of this strain gauge experience I learn almost all on that cartridge and again confirm what I heard and what I say to SD that time, that was IMHO a faulty design.

other sample of this kind of skills you live it with me in your audio system last time I was there.
you put me first music through CDP and 30-40 minutes latter switch to your analog rig ( cartridge: PC-1 ) and you remember that after few minutes I ask for a change the load impedance ( that was around 500 and change it to around 100 ohms. ) because what I was hearing was not so good, things improve with that load impedance change.

Latter ( 10 minutes more ) I told you that something was wrong with the system because the right output level on the speaker system was lower than the left side, you check that the volume be in the right way in the preamp and heard again and confirm that the output on thr right side was lower through analog because on digital everything was right on target.

Not only you was hearing the system with out take in count this " problem " but ( in the afternoon ) six of your member group either take in count ( I check that the volume in your preamp where even/similar position. ).

In other place with a different system I made a comment to the audio system owner: Sir you have bad bass resonances here and he told me that no one ever of his audio friends ( including audio dealers ) never told him any comment on this problem that now and after my comment he take in count, I have to say that this audio system is in a dedicated room with 200K+ on audio equipment.

All these samples/experiences/comments can tell you that I'm training in deep for make that kind of " work ", this skill does not comes by free or random it is a hard and time consuming training over the years. Am I prefect on this regard? certainly not ( far from there ) but this learning skill is what give me the knowledge/kno-how to evaluate my audio system quality performance and through many changes on it discern what is a real improvment change and what was only a different only.
This skill is something that any one can develop, I'm still in this learning curve.

Regards and enjoy the music,
Raul.

the SP10 has so much damn torque that you would think you really need something massive to hold down the turntable to sink all that vibration. Didn't Mark Kelly tell us that Sansui experimented something like this about that return torque that's causing the turntable cabinet to color the sound?

Absolutely

I agree that if Raul or anyone else prefers the sound of "naked," that's fine, but chassis rotation in response to motor correction is precisely what I'm hoping to eliminate. The only question for me is how far you must go before no more improvement can be had.

On my MK2 Wenge plinth and my MK3 Ebony I experimented with various isolation feet and the roller types low friction overcame the plinth mass and allowed the chassis to respond to the energy, making for the analog version of "digital jitter."

This convinced me that the chassis must not move, even microscopically. The only two options I've found that achieve this and still provide "isolation foot improvement" is (1) Still Point system with threaded riser, (2) A military sheet material I've been experimenting with some months. This military material has incredibly high sheer strength in the horizontal plane but compresses in the vertical plane absorbing bass energy relative to it's thickness and the mass (total weight) applied.

Fortunately I found some an engineer on the project that had specifications for load and thickness and this has made experimenting a more fruitful venture.

Dear Sp-10s: I think that everyone of you are realy satisfied with your own SP-10 mods aside the fun to do it by your self.

I already posted on other threads that as important as is the electronics, naked or non-naked, suspension, etc, etc, IMHO and for every single TT ( any ) the main and critical factor for it can show at its best ( neutrality ) is the build material on platter ( certainly the build material is important everywhere. ) if like Albert say:
+++++ " is how far you must go before no more improvement can be had. " +++++

my advise is to " explore " that platter build material. Btw, very complex subject for say the least.

Regards and enjoy the music,
Raul.