Based upon my own experience with the ART-9 playing classical music I agree with lewm that the distinctions made by AT between the two cartridges and the music they can play well are a lot of PR BS. Which is not to deny that they may be different.
When comparing the two cartridges a potential user should consider that the fair comparison is between the ART-9 and the ART-7 + an extra stage of amplification whether it might come from a SS stage or an SUT, each of which will intrude with its own colorations.
When comparing the two cartridges a potential user should consider that the fair comparison is between the ART-9 and the ART-7 + an extra stage of amplification whether it might come from a SS stage or an SUT, each of which will intrude with its own colorations.