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Confused about compliance matching with airbearing

Chrome doesn't let me post more than a paragraph, so let's try again.

I am ordering a Soundsmith Voice. I currently use a 20cu Grado with no issues, 10hz vertical resonance, on an MG1 airbearing.

Petere advised against the 28cu model which confuses me because Trans-Fi owners are use 32cu carts with what seems to be much more lateral mass.

Should the horizontal effective mass be high in order to use high compliance?

"Keeping the wand short reduces resonances within the arm which typically colours the music. It is probably one of the major influences contributing to the overall sound of a tonearm. Manufacturers of conventional pivoted arms go to great lengths to try to eliminate resonances. They have a hard job!
Together with a lightweight slider, Terminator has the lowest lateral inertia of ANY airbearing tonearm on the market weighing in at just over 80g including the saddle, counterweight & cartridge, allowing safe tracking of the fussiest high compliant cartridge."
doctorcilantro
doctorcilantro OP
59 posts
 
The ET2 is quite low mass then. I'm at about 60grams with cart, counterweight, and entire arm assembly on the MG1.
dgarretson
2,394 posts
 
Rcthweatt, The ET manual is a well-spring of technical information, but I am confused on the subject of horizontal mass. If I understand correctly, moving horizontal mass is 25-35gm wand+manifold, plus up to 40gms counterweights, plus optional 18gm damping trough.
doctorcilantro OP
59 posts
 
Yeah, I do think the counterweight was overlooked. The damping trough is attached to the horizontal moving mass asemmbly....interesting.
rcthweatt
4 posts
 
Dgarretson, Drcilantro-

Ooops! You are correct, as p.5 indicates, spindle 14g,arm tube 11g, so 25g w/o CWs, which are 5 &15g, small and large. I assume the spindle weight includes the CW arm, and the clamp, post, etc. (I'm not disassembling to weigh it tonight!)including the lead piece which slides into the clamp. So, my horizontal mass would be 25+5(1 small weight)+8(cart)+1(screws, also neglected),39g;using 9 cu, 8.49HZ,which still agrees pretty closely with test record. Now- this cu figure is at 100HZ,which isn't the frequency we're at, 10 HZ would be better, so supposedly one should multiply this by 1.5-2,or halve the static figure(35); trouble is, using these I get 6-6.9HZ: at those frequencies, arm is perfectly stable. Hmmm...not horizontal, but vertical resonance? 7+8+1g times 18cu(.000018), I get 9.378HZ, also close. Way to settle- add mass, and see if 2 resonance points develop..unless there's a test record with a wider range?
lewm
6,770 posts
 
For those with a technical bent, John Ellison described a simple and clever way to measure actual tonearm/cartridge resonance, over on Vinyl Asylum. I suspect you can find it by searching on "resonance" or something like that. But you do need some tools to do it.
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