Isn't there a point that the high frequency roll off can be shelved? ...
Yes, a number of people argue that the treble should be shelved around 50kHz because the cutting head was probably shelved there even though that's not in the standard. I've always figured that the mastering engineer should have adjusted equalization so the record sounds right when played back with standard gear.
The cutting head is hardly the only component in the mastering/reproduction chain that might have an imperfect response in the octaves above 20kHz. :^) Cartridges and tweeters for example will have much larger deviations. I figure, if one feels the need to compensate for these effects, you really need an equalizer of some sort.
If anyone really feels the need to add a shelf at 50kHz, it's a simple matter of adding a small resistor (267 ohms in Seduction, 316 ohms in Eros) in series with the smaller capacitor in the RIAA network.
