Tonearm mount on the plinth or on Pillar ?

There is a long thread on this subject started by Halcro, in the context of which he refers to the idea of separating arm pod and plinth, which he favors, as "Copernican".  I vigorously disagree with him; I agree with Ralph (Atma-sphere) that the two should move as one.  However, I do agree with Halcro on many other subjects, and I consider him a friend. Ergo this point is no longer worth arguing about.  He and anyone else can do as they please, and I will do as I please.  We'll both be happy, I am sure.

I will just say one thing: Moonglum, your statement that the tonearm and plinth resonate separately even if they are locked rigidly together is kind of an oxymoron; if they resonate separately, then the goal of tying them together rigidly has not been met.  And in fact, I think a lot of designs are imperfect like that.  It takes a very substantial structural linkage to achieve the proper resonant unity.

I also think that if you bolt an outboard armpod to a rigid shelf and also bolt the plinth to the same shelf, you are doing the right thing.  The last photo I saw of Halcro's TT101 set-up looked to me like he was doing that; it looked excellent in fact.

Dear @

pani: 23+ years ago I was looking how to improve the quality sound on my analog rig. I owned and own two Denon TTs: DP-75/80 and Technics SP-10s.

I took the alternatve to change both Denon TT plinths and instead to following using the wood plinths I start to use one green marble and one beige onyx plinths ( around 45 kg each one and beatiful looking " guys ". I still have it. ).
The overall quality sound improved by a wide margin. Two years latter I decided to try a new knd of plinth and the new plinth was: USE NO PLINTH AT ALL, mounting the tonearm in a separate " tower/pillar ".
Again it was an improvement but not so big as before with the stone plinths.

For me/in my case was there when the overall " naked " concept rised and years latter I brought here at Agon and other forums in the net.

I used in the SP-10s too.

The theory behind the Atmasphere pst is right and tha is not under discussion but try to help yu in your question.

Till today I never heard and never was and is any concern that with a separte tonearm mount tower the quality sound performance losted some kind of coherence or well-timed coherence presentation.

In my case I had no choice for Denon/Technics TTs, I was " obligated " to take the naked " road " that IMHO works really good it does not maters what theory say.

I think that as everything in audio exist trade-ffs here, at one side is the theory and at the other side the sound qaulity level performance in the non-plinth alternative.

Till today I did not and don’t read it a real/fact through listening scientific tests that confirm any single advantage to that theory. So leave it at rest and decide what you can think is your preference: though your audio distributor you can listening both alternatives and decide about.

Btw, It’s easy to measure if the frequency response, phase and amplitude of the TT ( plinth/motor/platter spinning, etc. ) is exactly the same at the tonearm directly because every kind of " joints " where those vibrations has to travel till achieve the tonearm it self can change.

Kuzma, between others, choosed to design some of its TT models with an external tonearm tower and I never read any customers compliant about.

In audio be too dogmatic not always gives the better results.

Btw, that youtube link can say many things but can’t prove something scientific. Seems to me that the TT in that video is a Technics that with its own plinth is really " terrible " and with that Sonus cartridge/VPI the resonant frequency is around 4 hz. That Technics plinth and the resonant tonearm/cartridge frequency are against in between.

My opinion is try to mantain the phono cartridge as aisle as we can, at maximum of the posibilities. Any kind of vibration/resonance produce and increment many diferent kind of distortions that goes against the quality sound level.

An external tonearm moun ting tower is a way to aisle ( in some ways. ) the phono cartridge and does not maters if the external power is seated in a different platform that the TT.


Regards and enjoy the music,
R.