According to Ralph a line stage has 4 functions:
1) control volume
2) select input
3) add any needed gain
4) control the interconnect cable at its output
The last of these is the critical, as well as, the least understood one in his opinion. Ralph feels a *quality* active linestage will control cable artifacts better than any passive (and IIRC he has indicated in this thread the LSA is the best passive he has heard). From Ralph's design philosophy (true balanced differential, 600 ohm standard) I can see his point and even accept it. He's done the research, it's been substantiated, and it's evident when you hear his components working together. Pretty much why I'm willing to get a buffered version of the MP-3 to match up with my S-30.
However, high-end audio is more about single-ended than balanced (as well as more about mixing components from different manufacturers than matching them) and in a single-ended environment given some of the parameters discussed here and elsewhere regarding impedance matching and cable characteristics, I believe a *quality* passive linestage can competitively match up with a *quality* active linestage. Additionally, in my case the cost differential being such that money saved using a passive has allowed me to improve other areas of my system substantially.
Now as for designers who have spoken on the topic of passives, here is another opinion from Jeffrey Jackson of Experience Music:
http://www.jeffreywjackson.com/preamplifiers.htm
1) control volume
2) select input
3) add any needed gain
4) control the interconnect cable at its output
The last of these is the critical, as well as, the least understood one in his opinion. Ralph feels a *quality* active linestage will control cable artifacts better than any passive (and IIRC he has indicated in this thread the LSA is the best passive he has heard). From Ralph's design philosophy (true balanced differential, 600 ohm standard) I can see his point and even accept it. He's done the research, it's been substantiated, and it's evident when you hear his components working together. Pretty much why I'm willing to get a buffered version of the MP-3 to match up with my S-30.
However, high-end audio is more about single-ended than balanced (as well as more about mixing components from different manufacturers than matching them) and in a single-ended environment given some of the parameters discussed here and elsewhere regarding impedance matching and cable characteristics, I believe a *quality* passive linestage can competitively match up with a *quality* active linestage. Additionally, in my case the cost differential being such that money saved using a passive has allowed me to improve other areas of my system substantially.
Now as for designers who have spoken on the topic of passives, here is another opinion from Jeffrey Jackson of Experience Music:
http://www.jeffreywjackson.com/preamplifiers.htm