Technics headshell weight/ Audio Technica 440mla c

Hi, The headshell weighs about 7.5g with wires and I would guess from what you say, 5.67g without.

AT 440 compliance is 10 @ 100Hz = 18 @ 10Hz.
Calculations for resonant frequency use 10Hz figures.

Lots of people use 440s on the 1200. It should be a good match. I'd recommend supplied aluminum screws. I also replaced the headshell wires with silk wrapped ones and seemed to get nicer sound, although on a different arm.
Regards,

Thanks Fleib; I've looked at your contibutions and I am impressed by your knowledge in this area. I note the Technics 1200 arm has an effective mass of 12 g. as does the SME 3009 II, non improved. Does this mean that by simple subtraction both arms have effective masses of 4.5 gms WITHOUT headshell, as both the original SME headshell with wires and the Technics 1200 with wires both weigh 7.5 gms?? I find this interesting, as past implications have been on this and other forums that SL 1200 arms are heavy, when in reality they are the same effective mass as the 3009II, often thought of as optimal with high compliance cartridges such as th Shure V15III!

Hi Boofer, Effect mass without headshell might be a meaningless concept, depending on what you're trying to calculate. I guess you could look at it that way as long as you're using standard SME style headshells, but your results for E mass will be an approximation. Weight distribution might be different. Weight behind the cartridge should contribute less to E mass than weight at, or in front of the cart. BTW, calculations for resonant frequency are also an approximation. For an exact resonant frequency, get a test record.

I'm not positive if that weight distribution aspect is still valid. On Karma a physicist called Luckydog recently said, due to a quirk in the math for common arm lengths E mass is not increased solely due to length. I haven't quite digested all the implications. E mass is the same as MOI and distance from the center of rotation is a factor.

The 1200, like a Rega has a med/light arm suitable for a wide range of carts. Maybe people were thinking of the SME series III which has E mass of something like 5g? At any rate I suspect you're overthinking this aspect. While a "perfect" resonance of 10Hz is one octave above 5Hz warp frequency and one octave below the audible band, there might be other synergistic factors that are of greater importance. Where you get into real trouble is with a low compliance cart on a low mass arm. If the resonance approaches the audible band you're likely to get intermodulation distortion from that resonance.

The consequences of a low resonance frequency are tracking warps and susceptibility to mechanical and acoustic feedback. If that's not a problem then SQ is the other consideration. Often a med/high cu cart can sound sluggish dragging a high mass arm around, but it's hard to generalize. In such a situation arm quality, rigidity, bearing friction, etc. might be of greater importance.

If you're interested in a more detailed discussion you're welcome to join in here:
http://www.audiocircle.com/index.php?topic=88878.620
Bottom of page 32.
Regards,