I agree with your comments about SACD...I'm a big fan of the format.

I began my multichannel listening experience fully believing that the ITU standard (5 identical full range satellites, set equidistant from the LP and 1 sub for LFE) was the setup that would produce the best results at playback.

I soon realized that it doesn't work for the simple reason that low frequency reproducing speakers are very placement critical. But, so are the 5 satellites. The placement of the low frequency speaker must be experimented with in a given room, where the satellites have a very fixed spot and can't be moved.

The idea of stealing the bass from the satellites and redirecting it to a subwoofer then seemed a good idea because the satellites can be placed exactly where they are required to be and the subwoofer can be moved about until the best spot for it is found. Omni-direction of low freqs allows this to work.

Ahhhh, but then there was still the LFE signal. Once you adjust your subwoofer to optimally reintegrate the stolen bass into the soundfield from which it is stolen, you then have to suffer the summing of LFE into the same subwoofer.

To make matters worse, most pre/pro/receivers won't let you seperately adjust the slope/LP/phase/volume of the LFE. Only the summed signal can be manipulated.

If you buy a sub that's capable of withstanding the 121 Db onslaught of the Dolby reference level spec, it surely is worthless for music reproduction. Some software has a mild doubling of bass, some a brutal dose. Some have music soundtrack that will be summed with 'dinosaur footfalls'. Some even have full range info in the .1 track.

The answer really is simple. 1 sub for redirected bass and another sub for LFE. The LFE sub will have it's own preamp/processor with a crossover (not just a low pass filter), selectable crossover points, slopes, variable phase adjustment and a preamp that's optimized for LFE reproduction and provides unity gain from a player or preamp to a hi-fi amp or a pro sound amp. The high pass out of the LFE crossover can feed a 6th satellite.

You then set up your redirected bass sub to make your satellites happy while blending in the LFE sub as best suits the program.

Much less is demanded of each subwoofer. Intermod distortion takes a nosedive. The music lover is as happy as the HTphile. Heck, you can even mute the LFE if the double bass offends you. And, no more lost LFE because you choose a 40 Hz. crossover for redirected bass (though some preamp makers claim to send the full LFE along with any chosen RB low pass, it's really ridiculous to expect 1 subwoofer, or many, for that matter, to handle both signals correctly).

There are many more advantages to this setup, but the biggest one is in listening. Low frequencies are a beautiful thing when done right.

As an artist, please don't take away the LFE before we've even had more than a heartbeat's time to experiment. Anyone who tells me I can't write a dinosaur footfall into a piece of music or that there are no instruments but a pipe organ that have low frequencies (sheesh, I hate that one) is an arrogant fool with the imagination of an engineer.

I designed such a low frequency processor, had it built by Dr. Phil (Marchand), custom built each subwoofer for it's specific chore using proprietary parts from around the globe, tweaked placement, room treatments and circuitry, all the while charting and graphing the in-room results against the summed-signal subwoofer system.

But, as I said earlier...it's really in the listening in the end. A discrete redirected bass sub system (or 2, if you prefer stereo low freqs) along with a discrete LFE sub system is the simple answer in production of and playback of multichannel audio.

Don't slam the door shut before it's even been opened. BTW, my newly designed 1 string bass requires 2 people to play it. Wait til you hear THIS baby.