Today as I was finishing up my jazz guitar lesson with superb jazz guitarist David Gitlen, while we were listening to a little Joe Pass on CD and LP on the big Altec loudspeakers, there was a knock at the door.
![](https://jeffsplace.positive-feedback.com/wp-content/uploads/2020/10/PA220012-1024x768.jpeg)
Audio Note (UK) AN-S4 step-up transformer.
It was a delivery person dropping off an Audio Note (UK) AN-S4 step-up transformer. What an unexpected and really nice surprise!
Peter had mentioned to me that one would be coming my way for a listen, but I wasn't expecting it today, so it made my day! Woo hoo!
There are several versions of the the AN-SL depending on the impedance of the cartridge you want to use in your system, and this particular SUT is the AN-S4/L - with 3 Ohm input impedance - which is designed to use with the Audio Note (UK) IO phono cartridge, which is on its way to me from Peter, as well as a few other goodies I'll tell you about after they arrive.
![](https://jeffsplace.positive-feedback.com/wp-content/uploads/2020/10/PA220014-1024x768.jpeg)
Audio Note (UK) AN-S4 step-up transformer.
Here's what the Audio Note (UK) website says about the AN-S4:
"The AN-S4 is a passive device, designed to convert the mainly current output of your Moving Coil cartridge (MC) to a higher voltage, low current signal of sufficient strength to allow a Moving Magnet (MM) phono stage to amplify it to a suitable level.
"Custom Silver Transformers
"The internal transformers used in the AN-S4 are manufactured by Audio Note (UK) exclusively. Each transformer is made from 0.1mm laminated super mumetal 250 and wound with 99.99% pure Silver wire. Each Transformer is then housed in a mumetal screening canister to minimize noise and interference.
"Low, Medium and High versions
"The AN-S4 can be supplied in the following standard versions to suit the internal impedance of your cartridge:
AN-S4/L - 3 Ohm input impedance - Primarily designed for use with the Audio Note (UK) IO range
AN-S4/LM - 4 Ohm input impedance - For cartridges with an impedance of 1 to 2 Ohms
AN-S4/M - 16 Ohm input impedance - For cartridges with an impedance of 4 to 6 Ohms
AN-S4/H - 64 Ohm input impedance - For cartridges with an impedance of 16 to 21 Ohms
![](https://jeffsplace.positive-feedback.com/wp-content/uploads/2020/10/PA220016-1024x768.jpeg)
Audio Note (UK) AN-S4 step-up transformer.
"Internal Impedance
"It is possible to use our transformers with cartridges that have greater internal impedance, or values that are outside the preferred ranges of the standard inputs, however, it is important to realize that an input impedance in the region of three to four times the internal impedance of your cartridge will usually provide the best results."
In the meantime, I thought I'd give it a try on my Ortofon SPU Classic. My Ortofon SPU Classic has an internal impedance of 2 Ohms, so that means that an appropriate SUT should have an input impedance of 6 Ohms to 8 Ohms, and the AN-S4/L is 3 Ohms, but just for fun I'll give it a try anyways just to hear what happens.
![](https://jeffsplace.positive-feedback.com/wp-content/uploads/2015/07/Ortofon-Classic-with-SPU-Woody-1024x768.jpg)
Ortofon Classic with Woody SPU tonearm.
However, the AN-S4/L SUT's 3 Ohm impedance ought to be just about right for the internal impedance of the Murasakino Musique Analogue Sumile moving-coil phonograph cartridge (1.2 Ohms), so that might make for a nice match.
![](https://jeffsplace.positive-feedback.com/wp-content/uploads/2017/07/14-Sumile-1024x683.jpg)
Murasakino Musique Analogue Sumile
I haven't had a chance to listen to the Sumile much since its review for lack of an appropriate SUT, but the AN-S4/L should be a nice match to try to the Sumile until the Audio Note (UK) phono cartridge arrives.
![](https://jeffsplace.positive-feedback.com/wp-content/uploads/2020/10/PA220012-1024x768.jpeg)
Audio Note (UK) AN-S4 step-up transformer.
Much more to come on the AN-S4 as I get it installed and give it a listen!
![](https://jeffsplace.positive-feedback.com/wp-content/uploads/2020/10/PA220001-1024x769.jpeg)
Audio Note (UK) AN-S4 step-up transformer.
Postscript: Ok, I couldn't stand waiting, so right after I finished this post I decided I needed to install the AN-S4/L and give it a try with my Ortofon SPU Classic.
![](https://jeffsplace.positive-feedback.com/wp-content/uploads/2020/10/PA220005-1024x768.jpeg)
Audio Note (UK) AN-S4/L step-up transformer.
I've got it installed, up and running, and am listening to Joe Pass' Intercontinental LP at the moment.
The Audio Note (UK) AN-S4/L step-up transformer at 3 Ohms might not be the best match to the SPU impedance-wide, but you'd never know it from listening to the combination, it sounds glorious!
I'll follow up with more detailed listening impressions in the future, but the Audio Note (UK) AN-S4/L step-up transformer sure has made a good impression. The sound is natural, detailed, rich, and superbly musical. This is what music playback should sound like!
Postscript II: I just heard from Peter Qvortrup, and the price for the Audio Note (UK) AN-S4/L 3 Ohm step-up transformer is $6198 USD.
As always, thanks for stopping by, and may the tone be with you!