I hope it's OK to agree to disagree
What you describe is more the headache for the engineer(making the mix), not the listener
. Indeed the separate LFE is a tricky thing. The mixing engineer should (at least in theory) check the mix (after monitoring on a full range set) also on a Satellite/Sub set-up (small speakers) and also folded down to stereo (perhaps switching back and forth between 5.1 and 2.0 a few times?).
In the last two scenario the low freqs are also combined, first one in the sub, second one in the main pair. Phase problems can be detected this way and should be dealt with.
Even when using the LFE channel with a sub the low frequencies are also combined, only this time "in the air". There can be phase cancellation too and more problematic, because on one spot it's different than on another spot.
Because of all this the routing, of the .1 Low Frequency Enhancement channel to capable mains, turns out to work quite good once the right level is dialed in.
All this extra work (and choices) for the mixing/mastering engineers would be unnecessary if, for music, 5.
0 would be used. At the listeners side bass management could take care of what is optimal for that set-up. On this part (in fact on most of the rest) I certainly agree with Neil and Cai.
But for some reason the fashion is 5.1, as it is the standard for movies (where .1 is used as Low Frequency
Effect channel)
[On Topic] the problem of the original question seems to be flawed bass management. Creating a .1 channel is a workaround, doing what your bass management should have done. Only such a disc will not be ideal on other playback systems.
[/On Topic]
Disagree? You want to
disagree?
Yep - that's absolutely fine.
LFE is a contentious thing in music authoring. The recommendation from the Record Producers Guild is actually to leave it alone & mix in 5.0, and if you do decide to mix to 5.1 then to treat the 5 main channels as full-range come hell or high water - you simply cannot even begin to second-guess consumer grade sub/satellite setups that are designed for DVD-
Video playback and not music playback.
The .1 channel should be considered
not as a subwoofer or bass channel, but as the acronym says - Low Frequency Effects. It was originally intended to be there so the bass response in small speaker systems could be extended down to around 20Hz, sometimes even lower. Where all the problems begin to creep in is in the typical "Home Cinema" speaker setup that is often - at best - 2 full range main L/R speakers, often floorstanders. Then a limited response Centre channel (hell, it's only for dialogue and we
all know that proper music engineers hate using a centre channel, don't we?) and even more limited rear speakers as all they carry is ambience.
This type of thinking & setup is 150% wrong for music playback, be it DTS-CD, DVD-Video, DVD-A or SACD. Setups for Audio should all be full-range across all 5 channels - or you are simply not hearing the music as it was mixed. I have long thought that this is the main reason multichannel music gets such a pasting from so many people - they simply do not have the right speakers.
When I were a lad, the speakers were considered the single most important part of our stereo setups. If you had the wrong speakers, you could have the finest amp/turntable in the world and it would still sound like crap. These days, speakers seem to be an afterthought for most people, who often buy according to how they will look, or worse still, how little space they will take up & if they can be hidden from view.
This is bad. Very bad.
Creating an LFE is not easy. When you are mixing from multitracks, it is a lot easier to do. When you are creating an additive LFE from an old Quad mix, it is almost impossible to get it right so that it sounds equally good across the board, and this is because of Bass Management, the fact that most people do not know how to set up bass management, and tend to leave their players on the factory default settings.
If you know what you are doing, an LFE can be created from a Quad mix.
I only know a couple of people who can do this reliably (and no, I am not one of them).
When mixing from a multitrack, it's easy.
What is hard is trying to ensure that the end user hears the mix as you intended it to be heard. And on a sub/satellite system, this is never going to happen.
In short - avoid where possible. Unless you
A - know what you are doing, or
B - really, really want to.:sun