External step-up transformer with Io or MP-1

Not sure why you would want to do that as I think each of these has sufficient gain w/o an SUT.

I have tried an external stepup into the Io at its highest and second-highest attenuation. The results were not good - no synergy whatsoever. The Io is meant to be used as a fully active phonostage. If you want to use stepups, I'd look elsewhere.

I'm not sure I want to do this either. I had no intention of trying it until I read some very positive reviews of a few SUTs and talked to a few people who use them even though they too have sufficient gain in their phonostages.

It is an interesting idea and one I have recently done with an Io Signature and an ARC MCP-33. I just completed an update to the ARC. The Io, set to low gain, was used to verify the ARC component functioned correctly after the rework.

I can not report how a SU transformer might work here as the ARC is a tubed device. The ARC has an adjustable gain of 16, 20 and 24 db. Compared to the standalone Io set at 68db gain, the Io/MCP-33 combination gave up a little bit of bass; there was some added noise and hum most likely due to the mess of cabling ..... but ..... there was a little more treble energy and perceived extension which is no surprise as this is often typical of ARC products, new and old. And the Io is a little soft on top. Portrayal of space, decays and placement of musicians was first rate with either configuration.

Overall, the Io/MCP-33 combination is very musical but not a typical use of either product. And again, this was only done for the sake of validating the functionality of the MCP-33. The added cost with a Jade Hybrid IC and a Stealth Dream or Dream State PC for the MCP-33 makes this an expensive setup .... a very pleasing result ..... but ultimately bettered by the Io on its own.

John

I asked Ralph Karsten (of Atma-Sphere) the same question at CES, in reference to a Shelter 901. He said it is not necessary, as the MP-1 has enough gain. I listened to the 901 into the MP-1 all year, and it sounded fine, NO noise at all.

That said, two friends recently acquired Bent Silver Step-Ups, so I will borrow one to use between the 901 and the MP-1, and compare the results.