Rerurn to Romy the Cat's Site


In the Forum: Analog Playback
In the Thread: Expressive Technologies SU-1 and cartridge output and impedance
Post Subject: Unless it is a full moon night…Posted by Romy the Cat on: 7/7/2011
fiogf49gjkf0d
 Paul Costa wrote:
What is the maximum output and internal impedance you recommend for cartridges when using the Expressive SU-1.  What would be too much for either.
It seem manufactures are pushing the output a little higher these days, and would like to know what would be too high.
I am sorry, I am not sure what would be “output and internal impedance”. I do not recognize cartridges output impedance. It might exist in some minds but I have no use for it. The internal impedance? I do not know. I do not select cartridges by impedance and or by transformer requirements. Someone who has a friability of many cartridges and many transformer options would build up this rules but it is not me, fortunately or unfortunately – whatever. Generally the lower cartridge impedance the better as it will drive impedance of primary lower and it is good for a transformer. But we do not deal with an adjustable impedance of cartridge but we deal with ready to go cartridge that happens to have some specific impedance.  So, a cartridge of 1R might sound different then a cartridge of 10R but they are very different cartridges and this difference might derive from 999 other reasons then impedance.  So, frankly I completely discard cartridge impedance. If I have a cartridge that happens sound good then I do not care what it’s impedance. If I have cartridges that do not sound good then impedance is not what I might deal with anyhow.

When you say “manufactures  are pushing the output a little higher these days” then I presume you refer to output voltage. Yes, they do and it is a good thing.   I ran into my SU2 a Denon with 0.125mV and MC Ortofone with 3mV. I think 3mV is a bit high but I do not think that at 3-5mV a transformer in any kind of danger.  I guess if you so worry then you might consult with transformers maker but I do not think that they will have unified decision. What I do not do is driving my Fluke 87 tester into the transformer primary. BTW, one transformer maker told me that it is perfectly save but the Expressive designer explicitly informed me that I must not do it.

The Cat

Rerurn to Romy the Cat's Site