[Peter Wieck]

Jerry:

I keep a 10-band equalizer, but at the same time I question the value
of installing such a unit in other than extreme cases, especially to
replace a function that is both effective and already in place, the OEM
crossover. Also, keep in mind that that OEM crossover was developed
over some 20 years of production of this particular speaker and its
children. (3, 3a, LST, 11, 10pi) and does a pretty good job. Note also
that none of the aftermarket 'acquired wisdom' on these speakers
suggests that the pots should be removed from the circuit, a couple of
contributors even caution against it. Apart from all that, I used the
term "more-or-less" when I mentioned crossover function. There is some
marked effect on its response, making your balance yet more
"tetchy"(but not impossible).

Once again, I urge you to borrow, beg, steal a brute-force amp and try
it with the pots bypassed but the fixed elements LEFT IN PLACE. This
adds back the element of protection that the pots provided, brings back
the full response of the crossover to its original intention, and still
allows you to play with the overall response with your pre-amp tone
controls and/or an equalizer.

On a purely techical level, I also question your contention that by
simply turning down the Volume Control (and therefore reducing the
potential for clipping), you are increasing headroom to the mid/tweet.
You are increasing both the simple resistance across the voice-coil and
the overall impedance (of course). This means that you will require
_more_ energy out of the amplifier to make the same voltage at the
speakers (watts drop as nominal load increases for most solid-state
devices). So what you gain at one end, you lose at the other. However
in this case, the speaker VCs are now acting as the system fuse... Pre
Ferro-Fluid AR domes are not so good at that... allow me to rephrase:
they are very good at being fuses, and blowing.

Energy Dissipation: You may think that the most energy going into a
speaker goes into the woofer. Not really. Take a simple operatic piece,
one of my favorites: Handel's "Let the Bright Seraphim" and the
test-piece I used for my biamping experiments. Although there is _some_
bass on that piece (kettledrums, and so forth), even those elements are
mostly above the crossover point to the woofer. The P/A on that piece
is well over 10dB, approaching 20dB. So at some of the loudest
passages, at least 70% (probably more) of the total energy delivered to
the speakers is above the crossover point to the woofers. I am not
saying that you are going to clip, but I am saying that you are sending
a bunch of energy (heat) into those speakers with all the designed-in
protections removed, such as they were. Bi-amped or otherwise. Not that
I am arguing with your scope and other instruments, but just do a
simple band-pass reading of the amp(s) output and see where the
frequencies (and associated energy levels) are.

Just some thoughts. What you have done seems to work for you, but as
much as you have urged me to try things, I also urge you to do the
same. I also really hope you have fused your speakers, the AR factory
had quite a bit of literature on fusing, and specified quite-expensive
low-loss fuses, not the little glass-bits that most use.

Peter Wieck
Wyncote, PA