Preamp 47K load. Cartridge needs 330 ohm

your cartridge is 0.35 signal strength; it's coil impedance is 2.5 ohms

the answer:

Exactly as said above: Step Up Transformer with a (+/-) 1:10, ratio (which is it's xFactor),

Like lewm said: result of 1:10 x factor will change your cartridges 2.5 coil impedance to 470 which will be 'shown' to your PV7 MM Phono input'.

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the math:

your .35 cartridge strength will be  Stepped Up (multiplied .35 x 10 and be increased to 3.5V, a perfect strength for your PV7 MM Phono Input.

Impedance load is a 'guideline', kind of a minimum that the cartridge wants to be 'shown to PV7'.

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Choosing a SUT, the indicators on the front often do NOT tell you the xFactor, you need to find out/ask which SUT has a transformer inside which can do a (+/-) 1:10 xFactor. 

i.e. my SUT, Fidelity Research FRT-4 (I had to find the specs) has optional indications on the face, the face option of 100 ohm results in an xFactor of 10.55. which results in 423 ohms 'shown' to your PV7 for your cartridge.

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I put copies of the research I did about SUTs as one of my Virtual Systems.

Click on my name, choose 'details', it will take you to a page with a list of Virtual Systems, one is named 'SUT info'. One column shows the xFactors.

Small print of scanned pages: temporarily change your monitor' ZOOM from 100% to 150%s. Put back to where it was, i.e. 100%. 

An xFactor of 12 would be good.

.35 signal x 12 = 4.2 mv, a very good signal strength for MM Phono Inputs.

xFactor 12 results in an impedance of 326 'shown to your PV7, very close to recommended 330 ohms

lewm

I just wanted OP (or others following this) to know, 1:10 is not absolute, as a matter of fact anything up to 1:12 will be good, 1:12 might be best.

I agree 1:12 is limited; and 1:10 is more common, however, IF the OP searches, asks for help, and gets answers like above, he can end up with 1:12 or very close (my FRT-4 has 1: 10.55, who would look for that?

imhififan

Good find, seems like a very versatile unit. Independent Control of Gain and Impedance it ideal for current and future cartridges.

Allasso was on my chart, but I’ve never seen one, and never know if what I find is old or current.

I don’t see PASS for an MM, but it only has ONE input, so who needs PASS?

PASS would let you change to an MM cartridge or headshell with alternate MM pre-mounted/aligned and leave the cables Tonearm to SUT and SUT to MM Phono EQ (external or internal)  in place, that’s a big advantage IMO.

samssa

another good find!