1. Two 8-ohm speakers in series (to
make a 16 ohm speaker), bi-amped, for left and for right sides. No speaker cross-overs. Each speaker having One 8-ohm tweeter and two 16-ohm 8" woofers in parallel. Speaker wires are our
DIY #2, without
Zobel.
2. Passive line level cross-overs at outputs of universal player, using y-adapters for left and
right.
The passive line-level two-way x-overs (simple RC dividers)
are designed as following:
1) Selecting R(ohm): R = SQRT(Zs * Zi) where Zs is output impedance of source (or pre-amp) and Zi is input impedance of pre-amp (or amp).
For example, R = 3000(ohm).
2) Let hi-pass capacitor Ch(uF) be constant at -6dB, Fh = 0.0007(MHz).
That is let the tweeter goes full range, then tweak the matching low-pass capacitor Cl(uF) for the woofer.
Ch = 1/(10.88 * Fh * R). Say Ch = 0.043 uF
Ch to (+), R to (Gnd) and output at C/R
3) Tweak the value of Cl (low pass capacitor) for best music:
Cl = 1/(3.63 * Fl * R), at -6dB, Fl = 0.002 to .005 in .0005 steps. Most likely, Fl is about 0.0025 to 0.004,
for example Cl = 0.036/0.030/0.027/0.022 uF.
R to (+), Cl to (Gnd) and output at R/C.
Build four indentically looking low-pass assemblies then compare blind to select
the best Cl value. There is no need to know the frequency ranges of the existing drivers under modification, just remove the bulky speaker x-overs then tweak Cl.
Note that it is futile to design double-stage passive x-overs for -12dB because they will behave exactly as x-overs at -6dB shown above, but with
the drawback of lower voltage output and difficulty to match input-output impedance.
3. Player is Pioneer DV-563A with HR263 plugged into 5.1 outputs and
MR273s at stereo outputs going into y-adapters for passive cross-overs. Our
DIY #4 with 47uH inductors was implemented for power cord of player.
4. Two stereo amps for bi-amping. Amps are Home Theater Direct HTD-2100, having full volume controls. Our
DIY #3, using 18uH inductors and
A263 was implemented. Also,
MA263s are installed at speaker posts. Regular power cords (cut short) for the amps.
5. Our DIY #5 was implemented through out, plus some sort of speaker stands.
