Tonearm mount on the plinth or on Pillar ?

Dear Pani,

The answer to this one depends on who you speak to.

The Cartridgeman, for example, swears by completely separate platforms i.e. motor/turntable/arm pillar for the air-bearing linear arm. For good measure he even decouples the Classic cartridge with a "spacer".

Although I like the Cartridgeman’s products a great deal I cannot reconcile the operation of the tonearm without close coupling (i.e. the so called "closed loop") but it wouldn’t stop me buying them ;^)

Technically, there might still be a closed loop even for the "separatist" approach except that the final connection is by means of a shelf or a platform. Then any variability would be introduced by whatever is being used to support/level the various elements e.g. 3 solid spikes relative to whatever material the supporting surface was made of.

Provided one could guarantee the T/T & tonearm stay in precise relationship at all times I wouldn’t see a problem. Trouble is that the tonearm is by nature constantly manipulated and messed around with by the User so personally I’d feel uncomfortable if it wasn’t locked down and immovable.....

Just my opinion though.... :(

True Ralph. What you describe is an ideal situation but it is a fact that tonearms & plinths, even when locked rigidly together, resonate differently e.g. tonearms will have multiple resonant peaks which are not shared by the turntable which help to give each tonearm its unique sound.

In a perfect world they would be in perfect harmony. It seldom detracts from the enjoyment of the music we eventually hear.

Turntable designers are incompetent. If only they could design something as efficient as this.....

https://www.youtube.com/watch?v=aqAUmgE3WyM

Dear Lew,

You're misquoting me. I said resonate "differently" not "separately". A subtle distinction but a real one nevertheless.

Do you disagree that tonearms resonate in the manner I described?

I think you're taking an over-simplistic view of the design brief. A tonearm will have a natural level of decoupling (point contact through bearings or a single point bearing). Even if the T/T chassis is heavier than an anvil there is a limit to the extent that such coupling can damp the behaviour of the arm(?)

Look at it another way, if such behaviour did not exist it would be pointless selling clip on dampers for tonearms, or using silicone fluid to help control it even in some of the finest engineered tonearms ;^)

A more graphic example is if you clenched a tuning fork in your fist, vibration would be suppressed. If you hold it in the proscribed manner it will operate but it's important to note that a massive object (you) is nevertheless still gripping a non-massive object (the tuning fork).

I don't know Halcro's outboard system but I haven't condemned any approach in fact I seem to remember endorsing what Ralph said ;^)

Kind regards,

Glad no one took my last comment about T/T designers seriously ;^)

I was joking of course. I actually have the highest respect for what they're trying to do. It's an unenviable task and by doing it they're only going to please some of the people some of the time.

No problem, Lew. I agree the Earth isn't going to disintegrate due to the nuances of definition of 2 words. Since you did ask, "separately", to me, means without touching while "differently" means they can be touching. That's all.

Yeah, the main causes of wiggle room that I can see are the main bearing and tonearm bearing/s unless you're referring to flexure in the chassis & armboard(?)

But the point I was making is that it's the overlapping contact area of those bearings that would determine how effectively the 2 are locked together i.e. from a damping perspective. Since you are relying mainly on those bearings to commute/handle vibration it can never be an effective way to damp the tonearm. By nature, the bearings must try to be as zero contact as possible rather than act like a 6" nail through 2 pieces of wood.

Seems to me it's a classic "Catch 22" situation?

Peter Breuninger states that he "would put this combo up against anything currently available" (scroll to 6 mins 50 secs on the readout).

Looks good enough to be Italian too. :)

It contravenes a lot of currently "fashionable" logic e.g. not putting the drive pulley right next to the platter which would have maximised belt contact around the circumference.

Shame he only plays it for a minute. ;^)

Although I’m not a believer, I’ve got to be honest, despite the brief exposure it did sound good. :)

(They do also make models with the linked chassis BTW....)

https://www.youtube.com/watch?v=Gdo2Yf3BArQ

This study trumps everyone... ;^)

http://www.theanalogdept.com/images/spp6_pics/TT_Design/MechanicalResonances.pdf