ESL57, banishing the sweet spot
Something I have thought about for a long time, adding a wide dispersion tweeter to the ESL57.
The sweet spot really is narrow for the top registers, so if you are not sat in the sweet spot the treble can seem a fair bit down in level.
So I've finally got around to it and sourced some HiVi RT1C-A Planar Isodynamic tweeters. They are 5 ohms so I have padded them out to 8 ohms, the drop in efficiency is welcome as the tweeters are well in excess of the '57s sensitivity. They are installed on top of the '57s as shown:
[IMG]http://i63.tinypic.com/spej9k.jpg[/IMG]
I've ordered some variable L pads to control the level which haven't arrived yet, so the sound is a tad bright (understatement) :eek:
I crossed them in at about 5KHz, they augment the '57s treble rather than replacing it.
[IMG]http://i64.tinypic.com/24vso7c.jpg[/IMG]
Has it banished the sweet spot? Totally annihilated it :thumbsup: