Subwoofers in the midrange...

I for one dont intend to go around measuring the distortion of my kit, it is enough to subjectively evaluate and keep what I like...

Maybe the distortion of my RELs match the distortion of my speakers, room and remaining kit, I can live with that very easily...

 

It's very dependent, Mike, on its order (as you've said, even harmonic distortion is generally less obtrusive), its frequency (we are more sensitive to hearing distortion in the mid-band) and its volume (as the volume increases, the distortion becomes less noticeable).

Also, of course, there are different types of distortion - harmonic, intermodulation, etc.

It's also true that different people have different sensitivities to distortion.

Incidentally, re. amp distortion (not my particular area of expertise, but)...

With some types of amp - particularly class 'A' valve amps and, even more particularly, single-ended type amps - the distortion increases with amplitude. So the louder the signal the more the distortion. Now, as human hearing is such that if the music is loud we don't notice the distortion, so with some amps partnered with suitably efficient speakers, amplifier distortion will be effectively zilch.

As they say, the first watt is the most important watt.

 

It could also be that a dipole sub would be much easier to integrate with your ESLs. Check out the Linkwitz site (and don't be put off by the initial look - this guy's a serious speaker designer).

 

7_V thanks for the link, I shall do some more reading. the ESL's are great all I need now is a little weight to the sound that I'm lacking. A dipole sub could be the answer.