Some cartridge recommendations

@backwash 

Then as Raul explained,.  you will either have to get a step up transformer or go to a high output cartridge. Soundsmith makes a high output version of The Zephyr called the Voice. I owned one and it is an excellent cartridge, but on the more expensive side. It will run perfectly with 50 dB of gain. You can get excellent transformers for less, but then you have the possibility of having a cartridge past it's due date. IMHO, unless you want to go all in on a phono stage with over 60 dB of gain you will be better off with a high output cartridge. There are several decent ones in the 550 to 1000 dollar price range. the Goldring 1042 and the Nagaoka MP500 come to mind as well as the Ortofon 2M Black LVB. Grado also makes a fine cartridge.  

@pindac 

I read that the MC10 had an output of 0.07 mv. @rauliruegas is sure to know the answer. I was referring to the Zephyr MIMC, I should have specified. The OP does not have enough gain anyway.

I already have a Step-Up Transformer, I should have mentioned that sooner sorry. It is from Ortofon, says STM 83 on it. Small round unit about the size of an inline fuel filter. I was thinking it would be good to get this out of the system just due to its age, along with the MC10. Maybe I should use what I have. Sounds like it's all reasonably good stuff. Again, I felt like the sound stage width and height was lacking with this compared to streaming Qbuz through my Lumin T2. Tonally it seems mostly ok.  Slightly less upper midrange low treble. I know I will not listen to it very much unless I can get more out of it. I am 65 years old and grew up on vinyl but never had a very good TT just cheap DD Kenwood with an Empire MM cart and later an Onkio with a very inexpensive Ortofon. The SAE tone arm on this unit cost more than anything I had back then. Since then I have upgraded everything several times to what I think is a very good sounding system. I Would like to play some vinyl for old time's sake but it just seems a little dead to my ears.

To recap system Modwright KWH 225i, Lumin T2, Oppo 105D, Tyler Acoustics Woodmere II speakers, stereo Rythmik F12 subs. The mentioned Panasonic Sp10/Ortofon analogue rig, All with Synergistic Reasearch Tesla cabling, DHL sub cables.

Dear @backwash  : Your SUT it's just not up to the task for quality. You need at least the Ortofon T-20 por the Denon AU-340, any of these will makes a quality way differences for the better.

Other thing that could improve your analog quality level is to make a check up to the cartridge/tonearm set up in parameters as: offset angle, overhang, etc that need to stay spot-on according the protractor you use. You can too fine tunning the sound " playing " alittle with the cartridge VTA

mijostyn, nominal output of the MC-10 is 0.1mv.

R.

Dear @backwash  : "  compared to streaming Qbuz  ". Today not only digital beats ecven top analog alternative that you should not make comparisons in between due that the signal sound that you listen is proccessed in two way different ways that are not comparable in between: apples vs bananas..

Now you can improve your analog quality level response if you change the cartridge ( MC10 ) for a MM/MI new cartridge that does not needs SUT and today MM are really good. This one can do for you:

Backwash, just to revisit the question of phono gain, you say your Modwright has MM and MC inputs. Then you go on to say gain is fixed at 50 db. That is not enough gain far an average LOMC cartridge, and it is way short of adequate for the MC10, which is among the lowest of LOMCs. If you move forward with this cartridge you are correct in thinking you need a SUT or some other way of supplementing total gain (e.g., a head amp or a current driven gain stage). If a SUT, you need at least a 1:20 turns ratio. Make sure you have enough gain before proceeding to conclude that vinyl is not worth the effort.