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I have heard that on the occasional rock tune, through electrostatics, the dynamics suffer somewhat as the amount of information/music and speed it is being played at overwhelms the hybrid design.
This criticism is from a couple of forum discussions elsewhere. How accurate would this assessment be? :music:
First :welcome: aboard!
I would say: It depends.
Placement can have a lot to do with how severe the rear wave cancelation in the mid-bass is for a particular speaker in a given room. Get that wrong, and you get a big dip between 100 and 400Hz, smack in the mid-bass, where drums and bass guitars have much of their energy in rock music.
If you put a good absorber /diffuser behind the ESL, say something like the
Real Traps Diffuser is ideal, as it absorbs energy below 600Hz and diffuses frequencies above it (ensuring they don’t bounce of the wall behind the speaker and back trough it, smearing the image). Now the speaker can really perform its magic.
I’ve spent considerable time measuring, testing and building various solutions to the conundrum of how to make a ML speaker ‘rock’, and the ultimate answer is to augment the mid-bass in some form, either through room treatments, some EQ or wholesale replacement with a mid-bass line-Array.
The best results of course to do all of the above at once
People who hear my rig can’t believe the bass/mid-bass energy it puts out (and that’s before I’ve really finished room treatments).
The other challenge with ESL’s and Rock, is that ESL high-frequency power curves are much flatter and more importantly, waaay cleaner than most dynamic speakers. So at high volumes, the speaker still ‘sounds’ the same. This is due to very low distortion from an ESL vs a dome tweeter. A tweeter will progressively distort as you push the SPL’s up.
This leads some listeners to be quite surprised by how loud the ESL’s can play without actually sounding ‘loud’; and that’s because everyone raised on dynamic speakers expects loud = distorted.
Bottom line, the differences in topology between dynamic and ESL lead to ESL’s having a flatter, cleaner high frequency power curve, while having a progressively compressed low-frequency power curve.
Dynamic speakers typically have progressively compressed and distorted high-frequency power curves, and often a raising (and depending on config) low-frequency power curve (and much of the raise in SPL is attributed to added distortion products).
Therefore, the ideal speaker is an ESL from mid-bass on up and a line-array for mid-bass to bass, and the biggest, baddest sub you can fit
Oh wait, that sounds like a
MartinLogan Statement e2 
