Kuzma 4Point Tri-Planar

Another Romy the Cat candidate.

And another...

Wood is a chaotic material comprised of millions of random grain boundaries at varying angles surrounding cells with differing sizes, shapes and densities. Such a structure tends NOT to allow standing waves (resonances) to propagate or reinforce each other. Acoustic energies which flow into wood tend to be repeatedly scattered into disorganized packets with randomized frequencies and amplitudes. This makes it easier for the arm and armboard to dissipate them, rather than reflecting organized energy back toward the cartridge

Really? Is this why instrument makers play with wood the way they do?? Seriously, don't make statements like this and expect to be taken seriously at the same time.

Yes, and at the same time a set of wood blocks can be quite loud, as can even a set of drum sticks. And they make instruments out of metal too- a dobro is a good example.

The point is that wood is not **inherently** non-resonant. If its going to have non-resonant properties, it will have to be treated, just like metal has to be treated. Anyone who tells you otherwise is pulling your leg.

I would think a further issue of wood has to do with dimensional stability, especially with respect to humidity. I know you can seal wood to a certain degree, but IME humidity will still seems to find ways to affect it. Anyone who plays an instrument or dealt with a sticky door has experienced that.

Although most metals would seem to have greater resonant properties, the big reason they get used in an application like this is that the properties are quantifiable. If you know at what frequency a particular structure will become resonant, it can be a fairly simple matter of damping it effectively by other means. We do this all the time with our preamp chassis- the front panel resonates at one frequency, the chassis at another, tightly coupled the two rob energy from each other and will not resonate. Empire did this with the platters of their 498, 598 and 698 models.

Wood is less quantifiable. Instrument makers are well-known for using a small hammer to strike a wood sample to see how it sounds. Same species, same forest, same glade, same tree and several cuts can all behave differently. I've built a number of flutes and experienced that as well

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.

Sorry Dan_ed, we'll just have to disagree on that one...