Does anyone have experience matching an Icon PS1 MKII with a Soundsmith Zephyr MIMC Star?

I have to suspect Icon installs a resistor across the secondary of the SUT, thereby reducing the load seen by the cartridge to 100 ohms, instead of the expected 470 ohms. Either that or the base load resistor at the MC inputs is 10K ohms instead of the standard 47K ohms. Either way, the problem is easily remedied. But I agree that the seller gave bad advice to ignore the issue entirely.

I have a low output Soundsmith cartridge (Sussurro MkII ES) and it sounds perfect through a 1:10 SUT that shows it a 470KΩ load.

I think you mean 470 ohms, not 470,000 ohms.  But you would not want to load your Sussuro at only 100 ohms.

Thank you Antin for the Soundsmith link. I could not find it. That is reasurring.

I have been in contact with Icon. They made the comment that transformers are largely self adjusting.  I also asked them for a schematic of the MC input. They are telling me that there is no schematic since it is merely a 1:10 ratio passive transformer with a required output load of 47KΩ. And that I should follow Soundsmith's advice.

I have contacted Soundsmith, and supplied them with the PS1 MKII Specs. I  am waiting for a reply.

I am also confused about the 100 Ωs. If Icon is using a 100 Ω resistor across the secondary. Then they should have notified me of that, or sent, what amounts to a schematic showing the 100 Ω resistor across the secondary. Which could easily be removed from the circuit.

My calculations were exactly the same as the Soundsmith link.. The source should see a 470 Ω load. Which is perfect. If the Sussuro is seeing 470 Ω. Then that is what I should expect with the Zephyr Star.

I am anxiously waiting for Soundsmith to weigh in on this. I will let you know what they say. But from what is stated in the link. It seems to imply that a 1:10 SUT should do the job of delivering a 470Ω load.

I am also going to supply Icon with that link. And inquire how the 100 Ω load is being calculated.

Since I am unfamiliar with SUTs. This has proven to be an education for me.

Thanks to all for your responses.

You would not achieve a 100R load by putting a 100R resistor across the secondary. God forbid! That would result in the cartridge seeing a 1 ohm load across a 1:10 SUT. But if they inserted a 10K ohm resistor, THAT would result in a net 100 ohm load seen by the cartridge. But it seems they have denied doing that and claim they use a standard 47K ohm resistor at the phono inputs. Which would indeed result in the desired 470 ohm load. (Cartridge load is equal to the value of the resistor on the secondaries divided by the square of the turns ratio; 10-squared = 100. 47,000 divided by 100 = 470.) They cannot have it both ways. So some info is missing OR in fact you have no problem.