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How to deal with a 1.0mV LOMC or is it HOMC

I have a vintage cartridge on its way to me and despite being very excited, I am also very curious as to how I should load it into a standard MM stage. It is spec'd at 1.0mV and 60ohms.

For my current LOMC's I use a step up transformer that has a 15x, 20x and 50x step up ratios. I calculated if I use the lowest setting of 15x and based on the load impedance of 60ohms, the MM stage of my amplifier would see an output of 11mV which would seem very high.

Alternatively if I took the step up transformer out of the chain the MM stage would only see 1.0mV which is way too low.

Can anyone advise how they have dealt with carts which have such an unusual output.
ateal

Showing 2 responses by johnnyb53

johnnyb53
3,510 posts
 
As a frame of reference, there is no way I can run my Benz M.9 into a MM section. It does not have enough gain and it sounds like crap because it needs to be loaded at 100 ohms.

That's a really good point. The real issue--if the output is 1.0mV or more--is whether the HOMC is set up for a 47K load or a 100-ohm one. 47K is the standard for MMs and MIs and most HOMCs. 100 ohms is typical for an LOMC. I think *that*'s the critical difference with a 1.0 to 1.7mV output HOMC.
johnnyb53
3,510 posts
 
I have an Audio Technica mono MC cartridge, the AT-MONO3/LP. It has 1.2mV output that's drama-free compatible with my MM-only phono stage, so I'd say 1 mV should work too. In my limited experience 0.5mV seems to be the de facto upper limit for LOMCs.
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