I need a headshell recommendation for Technics 1200 GAE

If I’m reading the equation correctly, Z is an independent term that is simply added to the calculation after being divided by three. Since you’re only concerned with the delta here, calculating the change in effective mass is (I think) pretty straightforward. Whatever total Z is, the only part of it that changes with the headshell swap is the difference in mass of the shell plus screws, wires, etc (call it the shell package).

If the original headshell was (let’s say) 7.5 grams and the replacement package is 16.5 grams, you’ve increased effective mass by 3 (16.5 - 7.5 =9 and 9/3 = 3 grams) since that’s the unit of measure here.

The change in counterweight position and effective length should be very close to zero.  If you sub in a heavier counterweight and don't move the cartridge, it will be zero.

Yes?

@martykl Incorrect. Adding mass at the headshell will also increase the center of counter weight to pivot distance. In addition, you’re also using the equation wrong for the calculation you’ve made.

I honestly don’t understand what the confusion is. Adding mass directly over the stylus, will increase the effective mass of the system proportionately by the same amount. The equation proves that.

Now the heavier headshell does not concentrate all of the extra mass over the stylus, but for all intents and purposes it’s close enough.

Micro Seiki had a tonearm with a sliding weight on the wand, the closer the weight was positioned to the headshell, the higher the effective mass became.

Technics had a small weight that attached directly over the cartridge.

SME Series III tonearm had lead weights that attached under the headshell to increase effective mass.

This is really a very tired discussion and has been beaten to death.

OP, since you have the ART9, I recommend keeping the effective mass as low as you can. The Technics headshell is a great aluminum made in Japan part. And it’s relatively light. You just got your turntable, play it several hundred hours to break it in and get used to the sound, before making any tweaks.

One recommendation that I can make is to replace the headshell leads to either Ortofon silver leads (they sound great, I use them) or silver van den Hul leads. SME also makes silver leads using van den Hul MCS150 wire. Great stuff. You can get any of those leads from www.analogueseduction.net they usually have the best prices and ship worldwide.

@chakster @martykl : This link can help about that tonearm effective mass subject:

http://www.cartchunk.org/audiotopics/ToneArmMechanics.pdf 

R.

Invictus - right you are, I missed the small m in the first term.  Since you can hold the distance of counterweight to pivot constant by increasing the mass of the counterweight (and nothing else changes), you would need to add the required incremental mass there to the sum I calculated.

@martykl and Z is equal to twice the mass... According to chakster's posted equation anyway.