MC cartridge output measurements


Can someone tell me what is the conversion ratio from the JVC 3.54cm/sec standard to the CBS 5.0cm/sec standard. In other words, if a cartridge output is measured at .3mv using the JVC standard, what would be this cartridge output using the more common CBS measurement standard. Benz and Zyx are using the JVC standard to measure their cartridge output while most other (if not all) cartridge manufacturers use the CBS standard. Thank You. Sly
smoffatt
It's 5 divided by 3.54 = 1.412.

So if your Zyx is the .24 it's .34 by the CBS standard, and if, like my Bloom, it's .48 JVC, then it's .77 CBS.

David
ARmstrod is correct if output in mV has a linear relationship to velocity in cm/sec and if any constants in the equation are equal to 1.0, which is probably essentially true, in this range of velocity at least.
This cartridge stuff gets deeper and deeper every week for me. I don't even know how smoffatt knew to ask this question. I've just been on the phone with vak discussing .1mv cartridges and their ability to achieve decent volume. Now i find that there are different scales of measurement! Urghh. Finding out there are various RIAA standards a few months ago was scary enough.

Anyway, is there a compendium or book to know "all things" phono? (Or for that fact, "all things" tube)?

Thanks to everyone
I give credit to A'gon member Nsgarch for first bringing this issue to broader attention. He's posted about it here a number of times. Where he first learned about it I don't recall.

One resource for "all" things phono (or tube)? That would be nice.

Here's what I do: read any-thing posted by any-one, any-where. Then try to remember each tidbit when appropriate!

I have the sneaking suspicion that most manufacturers now adhere to the 5 cm/sec standard, since that makes it appear that their cartridges have a higher output compared to ones with rated output based on velocity of 3.54 cm/sec. I don't even know where the 5 cm/sec standard came from or why it was introduced at all, since in the good old days everyone used the lower velocity as standard for rating cartridge output (at least to the best of my knowledge). It's kind of like turning the volume up to 11, a distinction without a difference.
Bonarigo, you're correct. It's .6777 and I was looking at the wrong digits. Good catch.

David
Lewm,

manufacturers usually list the spec followed by the scale, for example:

0.48mV (3.54cm/second, 1 KHz)

for the Transifuration Orpheus, which, as has been pointed out, would translate to 0.68mV (5cm/second, 1KHz) rounded up to the nearest 1/100th. You just need to notice and know the implications.