I recently purchased a Kondo KSL SF-z Step up transformer optimistically hoping this would work well with my Etsuro Bordeaux SE but maybe I didn’t do the maths
This has the 1,3 and 40ohm options with 1m of LPz silver captive cable. (The newer version has a12 ohm option which would have been ideal I suspect)
It sounds great but I can only use the 40ohm setting with the Bordeaux SE and I have to wind the volume up more than I would like on my preamp. Annoyingly it probably would have been fine with the the standard .25mv version.
I’d have expected the standard Bordeaux to want to be used into the 3 Ohm position on the SFz (actually the cartridge sees 30 Ohms in the 3 Ohm position) I guess the ideal for it would be a little higher but not as high as the 40 position (actually 400 Ohms)
A 30 Ohm load gives a ratio of about 1:40. That ought to be plenty to get the level you need. Is the sound quality of your SE diminished greatly by being used into the 3 position?
My Cobalt SE likes 1:15 on my HM7s although I have loads of gain from my phono stage. 1:30 is a bit too bright for my taste.
I believe some of the yanks on WBF with the Gold SE have had 1:10 slagle units wound as the optimal solution…
The 40 Ohm setting in the SF-Z is about a 1:10 ratio which is what you’d normally use for a cartridge with 0.4mV output.
Any other standard MC step-up will probably also be a 1:10.
As Edd says, I don’t see that turning the volume up is a bad thing unless you’re completely running out of travel. Remember, it’s an attenuator so lowering the range you’re using it in comes with a noise penalty.
I was getting some slight distortion when using the 3 ohm setting however following on from everyones comments I have been experimenting a bit more specifically with my phonostage gain settings and I can now get a good balance of output and clarity on both the 3 and 40 ohm setting. Both sounding really good now so its just a matter of which I prefer which I haven’t identified yet. I have the gain set at its lowest on the 3 ohm setting so the 40ohm gives me a bit more flexibility.
I’m going to withdraw this from sale while I experiment further. Thanks for the input all.
This might be a useful thread for others. Could the mods possibly move it to the HiFi section.
If this uses fixed load resistors, it shouldn’t be difficult to change those - plenty of us could do that for you if you’re not confident with a soldering iron.
No soldering needed. On the (Aesthetix) Rhea all the gain and load settings for each of the 3 inputs are configurable from the comfort of the listening position using the remote which is nice I just can’t understand why I didn’t mess around with the gain settings earlier. I was merely swapping my EAR MC4 sut out with the SFz and comparing with the gain settings I have always used up to this point.
As I expected the MC4 is slightly softer and warmer than the SFz which adds greater focus and energy. Both are enjoyable which adds to the quandary as the SFz cost over 3x more than the MC4 (which I rate very highly)
thanks. this increases shipping problems unfortunately… 
I just can’t understand why I didn’t mess around with the gain settings earlier. I was merely swapping my EAR MC4 sut out with the SFz and comparing with the gain settings I have always used up to this point.
