Also just to let you know that Nelson Pass originally designed the B1 buffer back in May 2008
http://www.diyaudio.com/forums/analog-line-level/80194-lightspeed-attenuator-new-passive-preamp-137.html#post1521766
to be on the output of the Lightspeed Attenuator so it could then drive low input impedance amps of 20kohms or less that some of his amps have that people want to use the Lightspeed with.
You can read all about it on the Lightspeed thread on diyaudio.
After that he released it in diy form with a passive pot for diyer's who wanted to use just a potentiometer as the volume control.
Cheers George
http://www.diyaudio.com/forums/analog-line-level/80194-lightspeed-attenuator-new-passive-preamp-137.html#post1521766
to be on the output of the Lightspeed Attenuator so it could then drive low input impedance amps of 20kohms or less that some of his amps have that people want to use the Lightspeed with.
You can read all about it on the Lightspeed thread on diyaudio.
After that he released it in diy form with a passive pot for diyer's who wanted to use just a potentiometer as the volume control.
Cheers George