Since you wrote about power (voltage/current) requirements of electrostatic amplifiers when playing back the usual audio content (generally up to 10khz?) with no virtualization, I would like to ask, with due respect to your knowledge, one question that I cannot find the answer myself.
Do you believe that such filter (a personal room impulse response, i.e., RIR + personalized HRTF) could somehow change the reasoning you made in that occasion to encounter the power (voltage/current) requirements of electrostatic amplifiers?
*I still guess/believe with no technical proof that directivity must have a relevant influence in a room response and decay, at least in mid an high frequencies. I would like to hear your opinion about that also.
Any kind of EQ can significantly modify the power requirements, but it also depends on how the EQ is distributed. If you look at the power distribution of music, the most "wattage" tends to be in the 60 to 500 Hz region, whereas the high frequencies take relatively little power. Also note that the power distribution of music also depends to some degree on what type of music you are listening to, although in general the power demands above 2-4 kHz are 5-20 dB lower, as pretty much all fundamental music frequencies are at or below 4 kHz, which is the highest that a piccolo or piano goes to. This is why tweeters in a speaker rated for 200 watts may only be rated a 1-2 watts and yet won't burn up. Now, bumping up the level by 3 dB, which is a relatively modest increase in volume, requires 2x the power. If you do this in the power region of music, say from 50 to 500 Hz, the overall power demand may double whereas if you do it at 10 kHz, where there is very little power used to begin with, the overall power demand may change very little. And of course, if the EQ drops a band by 3 dB over the entire 60-500 Hz region, you may need only half the power.
An example of this is the SR007 vs SR009. If you look at the specs, they are only about 1 dB apart in output at 1 kHz, however the 007 produces a few dB less sound in the 2-5 kHz region, which is the frequency range the ear tends to use to judge the overall loudness of the sound. So if you adjust them to sound subjectively the same loudness you have to crank up the volume a couple notches, which could represent 2-4x the power demand. This is likely why the SR-007 is considered much more power hungry than the 009 even though the specifications are very similar.
Without knowing what the exact EQ is, it's hard to know whether overall power demands would increase or decrease, or by how much, which could be why Dr. Smyth didn't comment on this. If you listen at levels that don't approach the limits, then an amplifier should be able to accommodate modest amounts of EQ, however if you listen at levels close to clipping, which apparently some do, then yeah, you'll probably get into trouble. Kevin Gilmore reports that one Head-Fier at a meet managed to clip a DIY T2 with its +/- 500volt power supply, which pleased the Head-Fier and scared everyone around him as it was clearly audible across the room - we are talking levels over 110 dB, about the same as a live rock concert, and close to the average human pain threshold. I'm not even going to go into how stupid this, just look at the number of older rockers who have significant hearing damage.
In terms of directivity, a more directive speaker with an anechoic flat frequency response on axis will have a rolled off power response in the room. For speakers in a box, low frequencies will be omnidirectional, while higher frequencies will be more directed forward, with the beam narrowing as the size of the driver approaches the wavelength of sound it is reproducing. A dipole will have a more uniform figure 8 directivity and therefore a more uniform power response in the bass to midrange, although again at higher frequencies it will become more directive - this is all basic stuff that you can read in any acoustics text. Not sure if you are asking something more specific than that.
