+1 for Raul reminding you guys that the cartridge per se does not have the job of conforming or not conforming to RIAA; it's obviously the combined effort of the recording engineer who applies the RIAA correction to the signal on the LP and then of the phono stage, which has to produce a flat frequency response by applying "reverse" RIAA.
If you read Peter Ledermann's statement and sentiments regarding RIAA and his strain gauge design, you will see that he recognizes there will be some lack of accuracy in exact conformation to RIAA, because he tells us that he did not put any corrective filtering into his downstream electronics, as apparently was done for some of the earlier strain gauge designs. That was his philosophical choice, because he feels that the filters do more harm than good. Anyone who is interested in the SG cartridge should listen first and then decide whether he or she likes the end result. In my opinion, there is no right or wrong here.
I get that the strain gauge type makes signal voltage in response to displacement of the stylus, rather than to velocity of the stylus. The RIAA pre-emphasis involves attenuating the bass response up to about 500Hz, with a 6db/octave slope. Then the frequency response is flat from 500 to about 2kHz. Then there is attenuation of the signal voltage from 2kHz and up with the same slope. All of our LPs have this deliberate RIAA frequency imbalance built into them. Putting these two bits of information together, I guess that SG cartridges must inherently make most signal voltage at low frequencies, the opposite of what happens with MM, MI, and MC cartridges, and that voltage then goes down as frequency goes up from bass to treble, in an approximate 6db/octave slope. In other words, the SG cartridges inherently correct for RIAA but apparently with some error with respect to the formal RIAA curve. One region where there would be error is that plateau between 500Hz and 2kHz; I expect the SG cartridge does not respect that flat area of the RIAA curve. Its response would just sail through that region rising at 6db/octave. So if one heard a "problem", I would not be surprised if it is in the midrange. But also, if the slope of the response of an SG cartridge from low bass to extreme treble deviates from 6db/octave, that too could result in an apparent RIAA error. Raul and PL had a vigorous discussion of these issues, I think to be found on the famous MM cartridge thread started by Raul. I agree with whoever said that one ought to judge the results for onesself. It would be interesting to commpare the SS version of SG with one of the older designs that did incorporate RIAA correction filters in the downstream black box.
