After Bob Olhsson pointed out that bass management is not such a good idea, teacue replied:
Quote:
Originally Posted by teacue  Thanks a lot for your help.
As you seem to approve it, I came back then to the first method I described.
Thanks for your suggestions.
I have only one sub in my studio and there is only one sub in the theater too.
I always thought mixing with bass management would be a good simulation of the theater PA.
At least since I do this, I get much better results as before.
Indeed, mixing or halb mixing in the theater would be an ideal solution.
Though a little bit difficult for me to realise with the half-full theater.
I will think about this idea.
In fact the situation is a bit more difficult as the music I produce is for playback for live singing during Musicals performance.
But I am already glad when at least the playback does translate well.
Best regards |
In a discussion group such as this, discussing this entire issue thoroughly without taking things out of context and getting them wrong is very hard.
I'm certain that with the proper context, Bob Olhsson's comment would be more clear.
Let me summarize, with the caveat that a thorough study of the subject goes far beyond this summary:
The title of this thread is LFE, and yet it has drifted into bass management pe se. Managing LFE as a channel and managing subwoofer(s) to extend the frequency response of the mains are part of a larger subject but must be distinguished carefully.
The two subjects to keep separate are:
1) extension of the mains to yield flat frequency response by adding one or more subwoofers
2) proper setup of the LFE channel
Both of these subjects are the provenance of a bass manager, but they have entirely different alignments and purposes!
I am guessing that Bob Olhsson was cautioning against using bass management in a professional monitoring system to a single subwoofer to extend the response of the mains. Bob will correct me if I'm wrong about what he meant. I agree that caution is required as to my experience and seeing one other surround house that implemented bass extension to a single subwoofer resulted in very bad translation. But once the crossover points were more carefully adjusted (crossing over to the mono sub at the lowest possible frequency that still gives flat total response) that other production house yielded good translation to other venues.
It's easier to NOT screw up a two subwoofer-based extension of the mains than a single subwoofer. Plus, my cautions in a related thread about using a 2.1 system for mastering, at least you know my position on the subject.
a) Let's briefly talk about the bass extension aspects:
All full range speaker systems are also "bass managed" in the primitive sense that bass management is just a crossover. Where this diverges depends on how accurately you set up your bass manager to emulate a discrete full-range system. For example, if you are competent and knowledgeable, you can add two subwoofers to a stereo system to create a full-range stereo system that sounds totally integrated and as holitistic as a full-range system. This requires great skill and practice to achieve. I've heard more "disconnected-sounding" subwoofers than well-integrated ones, so caution is advised on that point. Then when you decide to compromise further by extending the stereo system to a single subwoofer, the choice of crossover points becomes even more critical, the placement of the single sub even more critical, and your chances of getting it to professional level even more dim, especially without the aid of a high-end acoustical consultant. And if what you seek is translation without compromise, a casually-set up, single-sub-bass-managed system is not a wise decision.
As a secondary system set up in a different room to see how it might translate, I highly recommend it, however.
b) The LFE. The LFE channel in all surround systems but SACD is designed to produce 10 dB more level with the calibration signal than the main channel (within the LFE bandwidth---where people go wrong is to use full range pink noise and then try to adjust their LFE to produce +10 dB... this is entirely wrong. The one place not to skimp is in adjusting LFE. Use a spectrum analyzer. Also confirm when doing surround productions that the signal you feed to the LFE is band limited below, say, 80Hz). If you keep your LFE separate and use it strictly as an effects channel with its own source and NOT CORRELATED WITH THE BASS INFORMATION OF THE MAIN CHANNELS, and NOT TO SUPPLEMENT THE BASS OF THE MAINS, then the LFE setup and adjustment is far less critical. Where you start to get into trouble is if you reproduce or produce a surround recording where you decide to, for example, supplement the extension of the bass drum by "putting a little energy in the LFE". Then the alignment, bandwidth and accuracy of your LFE channel and sub become far more critical. This practice can only be justified in cases where extreme required bass energy would cause the regular channel to clip. LFE was designed to permit increased headroom, but the number of times in regular music mixing where that increased headroom is really needed are quite slim. In film production, though, I must tell you that my two subs, which reproduce the LFE together (for even more headroom!) rocks on those explosions!
Bob Ludwig uses an entirely separate subwoofer dedicated to LFE so he can see exactly how it is affecting his results. But even he could conceivably run into trouble in those dangerous cases where people have used the LFE channel to extend the power of the mains. He probably had to place his dedicated LFE woofer and phase it with the others so that he could judge the extension when it was being used for that. In music, a more proper (if "proper" is even applicable here) way to "extend" the headroom would be to route an entirely supplementary signal to the LFE channel that is one that is not fed to the mains at all, so you don't get into any phasing or alignment issues.... like a synth bass, for example, to supplement an upright or electric bass, and recognize that only people who have LFE connected will hear that synth bass. That could be "really cool"... and takes advantage of the LFE channel's increased headroom.
Bottom line: Your mileage may vary, your knowlege is required.
I still have a lot to learn on this subject and I'm not pretending I know it all. The more I learn, the bigger the mistakes that I end up making! Because I seem to already have made and learned from most of the smaller ones :-).
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