Are passive preamps better?

Just to represent the other 50%

I like my Sonic Euphoria passive a lot. The last active I had created a lot of glare which is now gone. The active before that did not provide enough gain. The one before that sounded flat. (Supratek, Joule, BAT - not top of the line but not exactly chopped liver)

No doubt that the rig sounds different with the passive then straight from source to amp. A bit darker and smoother. Maybe more emphasis on certain details. But NO glare.

For now I am happy - lots of detail. sounds great at low levels, no tube rolling ang$t. I am sure I will go active again but for now this is working for me.

Good question.

You bet impedance is an issue, actually the issue when pairing a pre and an amp. Impedance matching - or mismatching - between the pre output and amp input is the key to a successful pairing or two boxes that just aren't happy together... Call it synergy =)

A great deal can be found on the subject by those both more technical and erudite then I am - all I can contribute is that its great when it happens and noticeably not great when it doesn't. T'aint no subtle or illusory thing.