from time to time I've been looking in this forum and now. .. here comes my first post.
Since a couple of weeks I have a pair of this little full range desktop speakers: http://www.markaudio.com/plan/alpair-5-desktop-tl
They show a good soundstage and astonishing detail level. Much better than the bulky BR I used before. But the drawback is that they rather sound thin to me which may be fatiguing after a while. This is mostly due to room acoustics and listening position, high speaker fs and the (to me formerly unknown) "full range sound". I decided to keep them because... they look so cool
So I want to give them help by some simple electronics. I am going to test attached preamp. It is to cover three issues: Baffle step correction, notch filter on speaker (and badly coincidenting room) resonance, and a little bass boost.
Essentially it is a fet diffamp with BSC (R10, C4) and bass boost (R6, R7, C1, C2) in the feedback network. The output stage is an EF fed by a bootstrapped double T filter for achieving a fairly narrow notch at the speaker resonance at about 130 Hz.
Do you see any flaws in this? I'll apreciate any comments, especially on the miller compensation cap. May it be omitted since the OLG is rather low?