My experience is a bit different than most of what has been reported here.
I am definitely not an insect: my hearing dies well short of 15kHz, however the addition of the Townsend supertweeters to my Quads was a revelation: the entire sound stage became better developed (source is vinyl). I did not hear increased upper frequency 'hash': in fact the upper midrange is where I heard the most dramatic improvements (perceived improved clarity, lucidity). The overall effect: 'it sounds more real'.
I don't really 'hear' the supertweeters when listening, but it is quite noticable if you take them away. My non-audiophile wife was listening with me and clearly heard the difference when the tweets where taken out and put back into my system. I have also heard from other quad owners that the Townsend's enhanced their systems in a similar manner. The Quads do not have 'dc to light' frequency response so YMMV.
The addition of the supertweets is somewhat akin to the addition of a good, well integrated subwoofer; with a 'woof it's not merely the lower frequencies that are audibly improved, the upper frequency ranges also benefit.
I think this is one of those 'listen for yourself in your own system' situations. Supertweets cannot be dismissed as 'crackpot audiophile psuedoscience'. They can make an audible improvment in a high resolution audio system.
I am definitely not an insect: my hearing dies well short of 15kHz, however the addition of the Townsend supertweeters to my Quads was a revelation: the entire sound stage became better developed (source is vinyl). I did not hear increased upper frequency 'hash': in fact the upper midrange is where I heard the most dramatic improvements (perceived improved clarity, lucidity). The overall effect: 'it sounds more real'.
I don't really 'hear' the supertweeters when listening, but it is quite noticable if you take them away. My non-audiophile wife was listening with me and clearly heard the difference when the tweets where taken out and put back into my system. I have also heard from other quad owners that the Townsend's enhanced their systems in a similar manner. The Quads do not have 'dc to light' frequency response so YMMV.
The addition of the supertweets is somewhat akin to the addition of a good, well integrated subwoofer; with a 'woof it's not merely the lower frequencies that are audibly improved, the upper frequency ranges also benefit.
I think this is one of those 'listen for yourself in your own system' situations. Supertweets cannot be dismissed as 'crackpot audiophile psuedoscience'. They can make an audible improvment in a high resolution audio system.