One that uses autoformers. Once you try them, there's no going back. I love my ASL T1, and I’m sure the others are even better.
http://www.divertech.com/aslpassiveti.html
http://www.divertech.com/aslpassiveti2.html
http://www.townshendaudio.com/allegri/
http://www.dagogo.com/emia-remote-autoformer-review
http://www.audio-consulting.ch/?Products:Preamplifier:Silver_Rock_Meteor_AVC
http://www.divertech.com/aslpassiveti.html
http://www.divertech.com/aslpassiveti2.html
http://www.townshendaudio.com/allegri/
http://www.dagogo.com/emia-remote-autoformer-review
http://www.audio-consulting.ch/?Products:Preamplifier:Silver_Rock_Meteor_AVC