Choosing the right SUT for my setup



I’ve decided to add a SUT to my setup. My MC carts are a Denon 103R (14 ohms/0.25mV) and an Audio Technica AT-OC9XSL (12 ohms/.4mV). I’m trying to decide between two used SUTs: the Denon AU-300LC and the Denon AU-320, both having a 1:10 ratio. Would loading ideal gain for the 103R and the OC9 be best achieved thru a using a calculator and installing a resistor that can be switched for carts or testing with a trimpot then installing resistor? I’ve also seen writeups where the OC9 is put on a 1:12 SUT and 1:20 for the 103R; from the boards experience is that pushing overload, or its in a good spot?

jctyler

My advice if you want to build a SUT box is to buy the transformers from Jensen, and they’ll help you with the rest.

I have a SUT that has been built for me using Cinemag 1254's, I also have Hashimoto SUT produced by the same person.

I most enjoy the presentation of the Cinemag, they are less rich than the Hashimoto, but it is difficult to describe the Hashimoto as rich, it the only SUT in use. For the delicacy and refined presentation, the Hashimoto nails it.

Both the above SUT's can be said to have a variance of rich hue in their presentation when compared to a Head Amp.

What about a premade SUT by Jensen? The JT-34K-DX model# MC-2RR-H ISO-MAX series. The specs look good. Has anyone given this a listen?

@jctyler

I own the Jensen mc-2rr-L model and it sounds great. The H model I believe is the 1/20 step up, whereas the L is 1/10.

Tavish Design uses the Jensen transformers in its Adagio tubed phono preamp. That is the one I'm striving for in the near future. 

I don't really see anything wrong with that Ebay kit, all you really need is a well shielded box with decent RCA connectors. The CM-1254 are shielded in MU metal cans so the metal box is mainly to shield the exposed wires inside.

You might want to contact the Ebay seller that sells the finished chassis for plug in style transformers. He uses the very nice Hammond die cast aluminum chassis. I'm thinking he can sell you a chassis with all the parts and predrilled to mount it all in. Be worth a shot.

 

BillWojo