Thanks for the explanation of adjusting the demodulator pots; I see there is another thread in this forum on how to do this with any CD-4 disc.
The instruction sheet for the EPC-451 says "...the frequency response characteristics of this cartridge is equalized for RIAA recording curve in itself. Therefore it does not require the equalizer..." which suggests that no equalization of any kind is needed. Also, I see no evidence of any equalization for semiconductor cartridges in Lou Dorren's demodulator schematic. Also, a quote from Soundsmith, who offer a very expensive preamp for strain gauge cartridges:
"No "RIAA" filter circuitry is required or used in our preamp - just one ULTRA clean gain stage ... The Strain Gauge is a "displacement" device......which automatically compansates for the RIAA EQ"
However, I believe that the Panasonic and similar semiconductor cartridges' response to a record is not truly flat and does need some kind of equalization, witness this review of Soundsmith's preamp from dagogo.com:
"The strain gauge... doesn’t require the RIAA playback equalization. However, when a record is cut, it is recorded with the RIAA preemphasis curve and there are two “knees” (turnover and rolloff frequency points) that cause a dip and a peak to occur when not using the RIAA playback curve. Peter [of Soundsmith] has finally, FINALLY, fixed the issue. It’s one of the reasons the strain gauge hasn’t been my main cartridge—the funny frequency response."
I have also seen a published frequency response curve (in International Audio Review) for one of Sao Win's strain gauge cartridges (based on the same technology as the Panasonic) which shows a horrible looking midrange dip and high frequency peak (almost looks like an inverse RIAA response
).
The reason I'm pointing all this out is that I hope to correct for any frequency response issues in these Panasonic cartridges, I'm just not sure how, without spending about $10,000 on a Soundsmith preamp.
@: I'm wondering if the Panasonic SE-405 does this kind of correction.