kanchi
lewm (and others here) know this far better than me, I’ll do my best.
you asked "what is the difference between Impedance selector and load selector?"
https://www.ebay.com/itm/KONDO-AUDIO-NOTE-AN-S7P-MC-STEP-UP-TRANSFORMER-JAPAN/123923446228?hash=item... look at all the KONDO photos, the lower controls inside, they have pre-wired 5 different resistors each side. you simply spin the front selectors (two selectors: l/r are separate), the individually selected resistor’s loads are indicated on the face.
open/40k/30k/20k/10k/normal. Perhaps lewm can translate those front load #s to a level of understanding.
note: less costly units involving various resistors might have internal parts/dip switches/resistors ... some that need to be soldered in individually after chosen, cost saving methods whereby you do the work, avoid shipping back to OEM for a change.
the KONDO’s upper front settings relate to typical cartridges listed, 6 selectable x factors, again, perhaps lewm could clarify the numbers on the face.
I do NOT understand SUT front indicators given in ohms, my FRT-4 face shows 3/10/30/100 ohm positions. WTF? I want/need to know the x factors which are only found on the spec sheet: 35.84x/20.68x/18.27x/10.55x It is inverse, lowest ohm setting = highest x factor; highest ohm setting = lowest x factor.
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You are seeking the best COMBINATION of both signal strength and impedance out of a SUT presented to your MM phono input (typically 47,000 ohm).
Signal Strength
Your .95mv signal strength is uncommon as you know, so low x factor setting is needed, most SUTs are far higher x factors.
i.e. .95mv. x factor 5.0. Signal strength 4.75 (allow for some loss) lets say 4.5mv. I agree with you, 5x is good, 10x = 9.50mv is too strong.
i.e. allaso 6x would give you 5.7mv, some loss, lets say 5.5mv for round #s. I like that too.
i.e. my cartridge .3mv using my much larger x factor 20.68 = 6.3mv, say 6.0mv
5x or 6x? Having two arms, change headshell, another cartridge, to avoid adjusting preamp/amp volume when switching, I would choose the x factor 5x or 6x to get the closest matching signal strength of the other cartridge.
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Impedance. Even trickier.
You do need to find out your cartridge’s coil’s ohms _____?
SUT Output Goal/Rule of thumb: cartridge’s coil’s ohms 10x or a bit more.
i.e. my coil: 10 ohms 10x, goal 100 ohm or more.
SUT Actual: 47,000 divided by SUT’s x factor squared.
working backwards: allaso x factor 6 squared = 36. 47,000 divided by 36 = 1305. 1305 divided by 10 x = ideal coil impedance of 130 ohms or a bit more. what is your coil’s impedance___?
i.e. my SUT’s optional setting 10 ohm equals x factor 20.68. squared = 428. 47,000 divided by 428 = SUT actual 110 ohm (a bit more than the rule of thumb for my coil’s10 ohm 10x =100 ohm).
perfectly clear?
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all well as SUT math, but lewm’s comments and suggestions regarding equipment change/avoiding using SUT need to be seriously considered, as I say, I just got into MC/SUT a few months ago.
