Coming soon from RFC: Quality custom built SUT!

[Reffc]

I am currently developing a new SUT (Step up Transformer) for the audio market which will come in several standard versions:

1:10, 1:15 or 16 and 1:20 step up (20, 24 and 26dB gain) with others to custom order.

The standard loading for these will be 100 Ohms but each unit can be specified for a particular cartridge loading.
Capacitance loading may also be offered as an option for those wanting a damped HF response (helps to reduce sensitivity to resistive loading too which means a better cart/SUT match).

These will be supplied in custom built casings using high quality connections and will ONLY be available from RFC and a select group of dealerships.

Expect cost to be in the region of £300 to £400 which will be market leading for such high quality SUTs.

The transformers will be all hand wound by an industry expert and will all be custom designed and built to my own specification.

The specs for the 1:10 SUT which will shortly be offered on trial to AoS members is as follows:

FR (within 0.1dB): 20Hz to 20KHz;
FR: (within 1dB): 10 Hz to 38KHz

Resistive (reflected load): 100 Ohms

This will be passed around AoS members interested in reviewing or trying the SUT. Just leave me (on THIS thread) details of your MC cartridge and I can confirm whether the prototype would be a suitable match.

There will also be Special Edition RFC SUTs made in strictly limited numbers which will have a one-off finish and will use the very highest quality connectors and wiring. Price tbc but expect them to be very competitive compared with the competition.

[Wakefield Turntables]

I will do some prototyping for you on both my systems if you like. I have the following carts

Ortofon cadenza black
Koetsu black

[Reffc]

Thanks Andrew

cant get the internal resistance specifications for the Koetsu and on line resources list it as either 0.4 or 0.6mV! It isn't too fussy on loading working well with a variety of loads so should be fine with the demo SUT.

The Ortofon is quite low at 0.33mV and has a low internal resistance of just 5Ohms with a recommended loading of 30 Ohms. It would therefore require a 32Ohm resistor in parallel with the primary windings to be correctly loaded.

The Koetsu is therefore the better cart to use with the trial version of the SUT.

When it comes to production, for folk having several carts, I can custom build a SUT with switchable loading to suit various cartridges.