Cartridge Compliance


As a layman I need some basic help with determining the compliance of a cartridge. If the manufacture identifies compliance at 100Hz as 7×10-6cm/dyne how do you convert that to a compliance number similar to 16 µm/mN. Also what numbers would indicate high, medium and low compliance. I have review the forum and found a lot of info on compliance but not the answer to these questions. Thanks for your help
sgunther

Showing 1 response by dlaloum

Another poor innocent audiophile enters the netherworld of cartridge compliance....

Seeking in the fog for points of reference.... (all we need now are Scully and Mulder)

Yes those two measures are equivalent, and there are rules of thumb applicable to basic mass market rubber suspended cantilevers...

But they frequently are shown to be wrong when designers use different sophisticated suspension setups, and/or differing materials!

The other interesting yet awkward thing is that aiming for the ideal 10Hz resonant frequency (based on arm mass & compliance measured at 10Hz) - is only a partial story, there are plenty of examples where a setup sounds great running with res f of 8Hz or 14hz.

Damping plays a major factor, and a cartridge with a well damped cantilever has much wider latitude than one that is relatively undamped.

BUT - tests comparing identical setups varying only the level of cantilever damping (done by Ortofon in the early 80's) consistently showed that the lower the damping the better the sound!!
It's always a question of compromise with vinyl!

Grado's are some of the least damped designs - they have a strong following, and also a substantial reputation for being finicky about their setup. (not surprising given the undamped cantilever!)

If possible based your cart/arm matching on compliance at 10Hz... assuming the spec is published or you can find someone that has measured it!

Second best is to base things on the VTF - this is an indirect approach, but basically anything tracking at under 1.5g will be happiest in a low mass arm, and is likely to be over 18cu compliance... Tracking at 1.25g is usually 22cu to 26cu territory and tracking at 1g is 35cu+ territory.
Mid mass arms (most S-arms are mid mass) tend to be happiest with VTF's between 1.7g and 2.2g - compliances tend to be around 16cu to 12cu.

Looking at both compliance and VTF will give an idea of compliance AND damping.
A relatively high compliance with a higher than expected VTF, implies substantial damping....

Hope that helps

bye for now

David