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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

Showing 9 responses by folkfreak

folkfreak's avatar
folkfreak
1,349 posts
 
This is the SUT you should look for - as you can see it offers a high 35dB of additional gain which would give you what you need. 
https://www.ortofon.com/media/15289/mc-2000-t-2000-transformer-p2.jpeg

Unfortunately these are rather pricey but a SUT builder such as Bobs or MFA can build you a suitable SUT

https://www.hifishark.com/search?q=Ortofon+t+2000

As @jmcgrogan2 notes any SUT must be used into a 47k ohm MM input

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
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
folkfreak's avatar
folkfreak
1,349 posts
 
Everyone needs to keep a gain cascade calculator handy 😉

28dB plus 48dB plus 14dB gives 1.58v out for .05mV in which is probably half what most power amps like to see (if we know your amps input sensitivity that would help)

another 6dB is ideal to get you up to 3V hence the T2000 or XG-5 at the 32dB up level

Anyway if the OP can give some insight into his power amp that would be helpful
folkfreak's avatar
folkfreak
1,349 posts
 
@jdodmead regarding grounding I'd start by connecting the phono ground to the SUT and see how that sounds -- really it's a matter of checking what sounds best (most open and "solid") with least hum -- it may be the SUT, or leaving it unconnected. I'd be surprised if grounding to the phono stage rather than the SUT is best -- in fact it may induce a hum

If after all this you still get hum (and after trying moving the SUT around and away from transformers and power cords) you may need a more sophisticated SUT with a ground lift option. I'd be surprised however if you have these issues with an Ortofon -- I only have hum issues with my mono cartridge (which is another set of problems)
folkfreak's avatar
folkfreak
1,349 posts
 
If you like where the MC2000 is taking you an SUT that will work and suit your price ($759) is the MFA 632 at a 1:100 ratio

Scroll down this page for instance of its use with the MC2000ii
http://gpoint-audio.com/our-collection/music-first-audio/
folkfreak's avatar
folkfreak
1,349 posts
 
@rauliruegas as you very well know (if you are as well informed as you claim) MFA is the hi-fi arm of Stevens & Billington, a long established transformer maker. MFA/S&B wind their own transformers to order. The base model, which the 632 series are based around (I believe) is the TX-103, specs on that are available here
http://www.stevens-billington.co.uk/page103.htm

As all MFA products are built to order you can be sure they will match the needs of your cartridge (ratio, impedance, inductance etc).

Anyway I'm not trying to shill for MFA, I'm sure Bob's are just as good, but could not let Raul's slur go by
folkfreak's avatar
folkfreak
1,349 posts
 
@rauliruegas as in all things audio one has to make trade-offs. There was a long design conversation with Jonathan behind the particular decisions on what switching and functionality to include given my need for two cartridge inputs. In  a purist world I'd have a dedicated SUT for each and no switching but as the phono stage I'm moving too (VOSS) only has one input I needed switching at the SUT. I did decide against switched gain which was another option. Needless to say all wiring and switch choices are as good as they can be. As to issues with length of interconnect I'm having no issues driving 2M of WEL Signature
folkfreak's avatar
folkfreak
1,349 posts
 
@rauliruegas do you have some sort of problem with me? Have I ever commented on your system or tastes? I’m happy to invite you round to hear my system if you’re ever in the Pacific NW but in the mean time could you do me the courtesy of refraining from insulting my audio preferences or experience.
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