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Do I need a sut?

I purchased an Ortofon MC2000 cart from a fellow A'Goner, it is very low output .05mV, my phono pre is a Herron VTPH-2 which has 69db of gain and my pre is a Herron VTSP-3a(r02) 14db gain.
The cart sounds wonderful, but with such a low gain I have to turn up the volume by quite a lot. If I had, another source at that volume, I wouldn't be able to stand it. With the volume turned up so high I get a fair amount of noise between tracks. 
Should I be looking at an sut or just live with it the way it is? I found an Ortofon at a decent price, it has 24db of gain. Would that be ok to go into the mc input on the VTPH-2? The mm gain is 48db, if I plugged it in there I would only gain 3db(if I'm doing my math correctly) I will also be contacting Keith, but I thought I would ask here too.
Thanks
Jeff
jdodmead
folkfreak's avatar
folkfreak
1,349 posts
 
Regarding hum this is an issue endemic to SUTs and the T2000 is limited in the facilities it provides to manage this problem. My preferred SUTs from Music First Audio provide a ground lift option (in the case of some of the models including a partial lift via a load) that completely addresses all of the hum issues I have in my current multi-cartridge set up

MFA offer a version of their basic 632 model specifically for the 2000 series with a 1:100 ratio -- cost is $759. Anyway if you do go this way work with Jonathan at MFA and he will build you what you need. I'm sure Bob's can do the same
jdodmead OP
257 posts
 
Anyone know about this one? Fidelity Research  XG-5 moving coil step up transformer with selectable input impedance.
Low - 3 ohm or lower 34dB Mid - 3-18 ohm 26dB High - 18-40 ohm 22dB
I know nothing about Fidelity Research and can't find out any good or bad info on this unit, it's as old as my cart.
Probably a "swing and a miss" but thought I'd ask.
folkfreak's avatar
folkfreak
1,349 posts
 
The XG-5 is a pretty re-saleable SUT so if the price is right why not give it a try, you can always resell? The 34dB/3 ohm setting would work

Remember to budget for a quality pair of interconnects (of low capacitance as Al notes)

There's more helpful guidance including specifics on this model here
https://www.vinylengine.com/step-ups-and-mc-cartridges.shtml
jdodmead OP
257 posts
 
I found one that's not pretty, but  a super price. It's worth a try, let you all know what I find out, it will be a few weeks(coming from off shore)

Thanks for all your input

Jeff
itsjustme
686 posts
 
I think Al has it pretty much summarized.  Most transformers are intended to be used in front of a standard MM gain stage, for two reasons:  1) matching of gain, and 2) transforming of load. A MC stage typically has an input impedance of around 100 ohms. A MM stage typically has an impedance of 47k ohms. Remember, the transformer doesn't just STEP UP, it transforms from a low-impedance, low voltage to a high impedance high(er) voltage.  You need to match impedances as well as levels, and the 100 ohm MC stage would just bog down the transformer - it would effectively be driving a short circuit.  I bet your MC stage can be configured as MM.  All mine are - same basic circuit, different loads and gains.
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