Preamp 47K load. Cartridge needs 330 ohm

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!

I just wouldn’t perpetuate the myth that the OP needs precisely a 330 ohm load for his cartridge. If he goes away believing that then he won’t have learned anything.The Cello Miyabe is an MC cartridge with an internal resistance of 2.5 or 3 ohms, based on two different sources. (To the OP) Generally you want the input impedance of the phono stage to be about 10X the internal R of the cartridge. Therefore technically you could load your cartridge with any impedance greater than 30 ohms, on up to even 47K ohms. You could even go below 30 ohms load, but then you begin to sacrifice cartridge output. Many say they hear differences in tonal balance exquisitely related to input impedance with LOMC cartridges, but actual measurements usually don’t support this belief.

Thank you all for input.  Conrad-Johnson phono is 40 dB.  I have checked other preamps for moving coil, they would suggest 60 dB is a good target amplification.  So I need 20 to 24 dB.  The Chorale is rated at .35 MV.  I have feedback that suggests it is lower than that, maybe .25 or .15 mV.  Agree, don't need 330 ohm exactly.  Need to have a step up and be 100 ohm to 500 ohm.  My other pre-amp the Nagra PL-P is 58.7 dB gain and 330 ohm.  I feel that is a lowish and want a bit more output.

So what should I get.  I owned two Ortofon's in the past.  One called MCA-76.  The cleanest would be a transformer like Lundahl or Jensen.  Solder it inside the preamp and no need for interconnects.  I would like to stay under $ 1,000.  Happy with used step-up.