Talk at me about SUTs

My personal phono stage is a Lehmann Silver Cube which I absolutely love - it does the business in a completely noise-free and transparent manner when used with LOMC carts - no SUT required. Since I’ve had it, I’ve not felt the need to do more than try a couple of extra slot-in resistive loading options.

However the Devil provides displacement for bone-idle hands-that-should-be-doing-something-more-productive, so last night I popped my Puresound T10 in-circuit, adjusted the Silver Cube’s gain and loading and experimented with the T10s two settings.

The preferred option gave interesting results - with slightly curtailed frequency extremes (probably no more than is commensurate with putting extra wire and connections in-circuit), but an improved sense of dimensionality and drive (PRAT of old), which I liked.

The clearest downside was noticeably reduced harmonic decay in sustained notes.

The T10 is a lot SUT for the money, but I’d like at some point to explore something that will - ideally - gimme them gainz, but NOT at the cost of any aspect of resolution…

To that end I’d welcome suggestions of new and used, manufactured and DIY options in the £hundreds to explore, as I’ve given this topic remarkably little consideration.

Main carts are Ortofon Cadenza Black and Hana SL.

Ta.

Get thee to Sowter as a start.

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You need a full time job and these fanciful exercises will subside :nerd_face:

Slagle http://www.intactaudio.com/tran.html

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I just googled ‘Tribute Transformers’ as I used to own a lovely 10:1 SUT by them.
Pete stuck the transformers in a box for me and I used it very successfully with a Shelter 901

It looks like Pieter Treurniet has slowed down his output and semi retired but there will be stuff on the second hand market. It might be worth contacting him and seeing if he has any stock left.
The ones I owned did the rounds a bit and used to turn up in the classifieds of the Wam but I am not sure who has them now.
Papa also owned a pair which are also doing the rounds.

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Wouldn’t you need to have different loadings when you swap these?

Hana Suggested Load: 400 Omms
Ortofon Recommended load impedance - > 10 Ohm

Just one of many wormcans Paul - the Caddy actually thrives best on a 47K load; the Hana I have yet to nail down as I’ve not put enough time in with it.

Of course introducing a SUT + extra cable changes the nature of the composite load seen by the carts, so loading at the phonostage needs experimenting with too.

SFAIK the T10 isn’t resistor loaded, but it doesn’t say and I’ve never had the lid off. Dave Slagle seems to prefer SUTs unloaded…

…aaaand down the rabbithole we go…

Intact audio or hashimoto would be where my money would go.

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Yep, mine is a Hashimoto.

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Nice.

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The T10 shows 38 or 150 Ohms (1:36 or 1:18) depending on which way the switches are placed. (it has 2 75 ohm coils that are connected either in series or parallel). While it works well enough with the Hana on its 150 ohm setting it’s probably fair to say that the Hana would likely be best paired to a 1:10 or 1:12 ratio SUT.

The 1:18 setting of the T10 should go pretty well with the Cadenza Black giving a healthy 5-6 mV for an MM stage.

Hashimoto’s HM-3 seems to offer 1:20 or 1:40 so still a little low impedance wise for a Hana. It might be worth looking at Lundahl’s offerings for a 1:10.

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Hi Paul,
I’ve got a Bob’s Devices step-up with Sowter transformers, switchable between 1:10 and 1:20. It’s sitting in a drawer waiting for me to set up a stereo in the attic (3 years and counting :roll_eyes: ) - let me know if you want to have a play with it & I’ll post it over to you.

FWIW I found this on his website:

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I have an unbranded sut here if you fancy a play with it.

Used it with a Hana and Koetsu,no idea what the ratio is though.

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I have a Bob’s Devices SUT, which I believe has the Cinemags. You are welcome to try it.

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Maybe a used Silvercore might suffice?

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Happy to loan (post) you my HM3s if you want to try them for a couple of weeks, though as Guy says, may not be a good match anyway. But the offer is there.

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If you really want to piddle around i have a pair of bare Cinemags, will happily post 'em off to you and you can wire them up as you want, see what you think of them.

Have a pair of Hashi 3sin a box you know of ::), wired switchable between 1:20 and 1:40 with an earth lift. You are welcome to a loan for a month or so if you would like to try them.

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For my money a pair of Slagle in whatever ratio is appropriate and in copper are good value (silver is 'spensive, however).

@Mrs_Maureen_OPinion - fwiw, Dave’s don’t need secondary loading, but loading across the primary to fine tune the impedance the cartridge sees is appropriate. That’s normally how I wire his stuff up when I use it.

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A quick and heartfelt “Thank-you!” to everyone who’s offered various loaners. Very kind :+1:

Thanks Pete. I spent some time reading relevant posts on his forum… After I’d taken my brain out and given it a good scratch, it seems that he prefers to avoid loading 1ry and/or 2ry if possible - with the silver cube you have the usual cartridge loading values at the inputs, plus 1 bay into which you can slot anything you like. Given the Cadenza sounds best with ~47K (and fairly crap with anything significantly less) without the SUT, but adding the SUT into the mix curtailed some of the performance at that loading - I’ve popped the next lowest value resistor I have into that bay - 30K, which seems to provide a clear improvement in all areas - frequency extremes are back, resonant decay is back, voice articulation is clearer, but I still have the gains - better PRAT and dimensionality.

FWIW overall gain is very close to the Silver Cube in full LOMC mode.

Now it’s more of a case of seeing if a higher quality set of windings has anything to offer…

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