Kuzma 4Point Tri-Planar

Lewm, one bolt is plenty. The surface contact area between the brass mount plate and the "headshell" is about 1 x 1/2". If there were vibrations not allowed out of the cartridge, or not drained away through the arm and base, you would have heard that as a nervous presentation. I assume from your comments that there were no such objectionable issues.

I think this just about says it all, right here ...

http://www.youtube.com/watch?v=UeK5EHZaq6A

Lew, I agree that an armtube's internal energy transmission properties can only affect energies which cross the headshell boundary into the arm, and the design and materials of the cartridge mount affect that transmission.

FWIW, the single-screw plate design seems to provide some effective coupling in Schroeder arms. For example, I've A/B'd the Model 2 with a carbon fiber tube vs. a pertinax one. (Pertinax is a composite of resin-bonded paper fibers, somewhat similar to a treated wood, though less dense and chaotic than the exotic hardwoods used in the Reference and Durand's arms).

Audible differences between those armtubes were readily apparent. Pertinax provided a lower sound floor and greater individuation of tones than carbon fiber, which is consistent with my blah-blah above. In this case at least, the one-screw cartridge/headshell plate passed sufficient energies so that the energy transmision properties of the armtube material itself made some audible differences. The cartridge/headshell connection of the Durand design is virtually identical, so one would expect similar behavior.

That said, there is a boundary so some energies will indeed be reflected back toward the cartridge, as occurs in every tonearm. My only point was that whatever energies *do* cross that boundary into the armtube will be more effectively dissipated by a material with a chaotic structure than an organized one.

Hi Mike,
My remarks to Doug were merely meant to indicate that there is some question in my mind whether the cartridge vibrations have an unimpeded path into the wood arm tube in the first place. If the mechanical energy put out by the cartridge cannot get to the wood, then those properties of wood cited by Doug would not be of any benefit. Because the rudimentary headshell consists of a piece of brass(?) held at an angle against the flat surface of the wood, I wonder how efficient is the pathway of energy transfer. This all goes without saying that I heard the Talea in a system using speakers like mine (Sound Lab) and amps like mine (Atma-sphere) and absolutely did like what I heard, very much. So regardless of the physics and these airy discussions, the Talea does a lot right.

hi Lew,

my comments were not any sort of criticisim of yours. only that i don't know so much about cause and effect, but that i hear the result.

i know that Joel Durand has tried literally hundreds of arm wand materials and shapes and also has access and skills to use many various analysis tools. i've been directly involved with listening testing of material differences for various bits of the Telos and have heard differences i would have never expected.

i agree that using a wood arm wand and a single screw to attach the cartridge plate to the wood arm wand appears on the surface to be less than optimized science....and your's and other's reactions are understandable.

i'll leave the scientific discussions to others.

best regards,

Dougdeacon, I think the thing I am reacting to in your posts is the word 'chaotic'. What meaning/context are you using that word? As in Chaos Theory? BTW that is the meaning that I used.

I maintain that wood is relatively unquantified with regards to other materials. You can have two sample taken from the same board side by side and have different properties. I have yet to see any that I would consider 'non-resonant'. 'Non-resonant' would be materials like E.A.R.'s 2003 compound or some of the damping materials made by 3M. Wood will still need damping materials to really control it.

Am I just being too literal??

Something else that has bothered me in this discussion: people have been talking about vibration moving from the cartridge to the arm.

FWIW, the cartridge should have no such vibration, being held in locus by the arm. The difference between the motion of the cantilever and the cartridge body will effectively be describing the resulting output signal. Now it **is** possible for the arm tube to move, sympathetically due to vibration elsewhere in the room, most likely from the loudspeakers. This can color the presentation as this vibration can be added to the locus of the cartridge body.

This is why an arm tube should be damped. A very simple proof of this is to use an undamped tone arm to make a tape recording without the speakers playing. You will find that it sounds quite a bit different (better) when compared to the same track but influenced by speakers playing at the same time.