To LFE or not to LFE?

[Dmax]

In the instruction manual of my sub they recommend using LFE only if im using my HT system for movies only (not music) as it will create more (boomy) bass that they dont consider suitable for music.I listen music half of the time using my HT system and I actually like the extra bass in my music but I dont want to go against the recommendations of the subs manufacturer.What should I do? :confused:

[noddin0ff]

The customer is always right.

[GMichael]

Listen to it anyway you like.

[Dmax]

I want to follow the recommened instructions of the subs manual but to hell with it,I really do like the extra bass in my music and the bass is not overlaping as the manual insist it would be.At least not to me.Thanx!

[GMichael]

the bass is not overlaping as the manual insist it would be.

It depends a lot on your system. If your main speakers don't go down below 60htz then you need the sub. Even if they do go lower, listen to them in a way that makes you happy. If it booms too much, turn it down.

[kexodusc]

Wow! That company is either very honest, or very stupid.

If you prefer it, that's all that matters. A good sub should be well suited to do either. If it's not good for music, it's probably not good for home theater.

What sub is it?

[Dmax]

Wow! That company is either very honest, or very stupid.

If you prefer it, that's all that matters. A good sub should be well suited to do either. If it's not good for music, it's probably not good for home theater.

What sub is it?Its a Athena Tecnologies PS-A 400 that has a( LFE Direct In )outlet but only recommend using it for movies not music.For movies and music listening they recommend using the (Sub In) outlet for both.

[kexodusc]

Sounds like maybe there's some EQ'ing going on behind the LFE input, though I don't know for sure. SVS does this with some of their subs. . Go with whatever sounds best to you.

[Woochifer]

If you have the subwoofer properly calibrated, then you should not hear extra bass per se, but fuller and more extended bass. The purpose of the sub is basically to take your system down into those lower octaves that your main speakers cannot render properly. And that will benefit music and movies equally. You should definitely check the levels with a SPL meter. In general, you want the subwoofer set about 4 db higher than the mains.

Boomy bass is generally created more from placement and room acoustics than from tonal variations with the subwoofer itself. With small to medium sized rooms, the boundaries reinforce the lower frequencies, and the shorter dimensions create standing waves whose effects will vary depending where you are within the room or where the subwoofer is positioned. It's those standing waves that alternately boost and cancel out the bass at different frequencies. I've seen room-induced peaks go as high as 30 db at certain frequencies. In those cases, the bass will sound unbearably boomy when the note hits those specific frequencies, but sound lifeless everywhere else in the bass range.

The only way around this is to find a location to place the subwoofer where the bass sounds fullest and most even. If you still have issues, then you'll have to go with room treatments and/or equalization. I use a parametric equalizer with my sub to flatten out the three biggest peaks that my room creates at the listening position. The improvement in sound quality before and after applying the equalization is huge. By flattening out the peaks, the sub integrates with the mains a lot better and allows you to hear what the bass is supposed to sound like.

[bacchanal]

A pretty knowledgable person (a recording engineer) once told me that the LFE channel is not the same thing as sub channel...LFE being soley for movie effects and stuff. I never really understood that, but this article offers a little insight, maybe. I guess it's just that there is a difference between consumer and commercial LFE. I don't know if this has anything to do with why the manual says not to use the sub for music, who knows. Plenty of people use successfully use subs for music. It can take some time and effort getting any given sub to sound its best, and woochifer is probably the man to talk to about tthat.

here is an article that explains a little about what LFE means to DD and DTS.
http://www.hometheaterhifi.com/volume_7_2/feature-article-misunderstood-lfe-channel-april-2000.html

here is a bit from the article


In a movie theater on the island of Utopia, with ideal hardware, any single screen channel should be capable of a clean 105 dB peak with it's own respectable bass. The LFE channel should be capable of a 115 dB peak. Drive all channels to the max and the system should be able to slam you with approximately 120 dB of bass information. Thank you Dolby.

Doing this right means having some powerful hardware. Deep bass at high output necessitates considerable air displacement. This in turn calls for large speaker drivers with appreciable excursion, which further calls for considerable amplifier power. For a modest cinema, two 18” drivers could be considered a practical minimum, with some road-show-sized theaters using as many as eight drivers, backed up by some 4,000 watts of amplifier power to deliver the goods.

[Dmax]

Thanx to all of you for your input and advice. I know a lot more tonight than I did this morning.

[Dmax]

It doesnt have an off and on switch but instead powers automatically and works extremely well but comes on several times a day for a minute or two then turns itself off when the rest of the system has been off for hours, should I be concerned and what would cause this? :(

[Woochifer]

A pretty knowledgable person (a recording engineer) once told me that the LFE channel is not the same thing as sub channel...LFE being soley for movie effects and stuff. I never really understood that, but this article offers a little insight, maybe. I guess it's just that there is a difference between consumer and commercial LFE. I don't know if this has anything to do with why the manual says not to use the sub for music, who knows. Plenty of people use successfully use subs for music. It can take some time and effort getting any given sub to sound its best, and woochifer is probably the man to talk to about tthat.

In the purist sense, you're right. The LFE channel rightfully refers to the ".1" track on a 5.1 or 6.1 soundtrack. And the term should not be equated with a receiver/processor's SUB OUT, simply because a SUB OUT might include other low frequency sounds that have been redirected to the subwoofer output by a receiver/processor's internal crossover.

But, with a lot of equipment out there, the LFE term is used very loosely. With subwoofers in particular, a lot of manufacturers have begun including two sets of subwoofer inputs, a conventional line level setup with separate L/R inputs and outputs, and a single RCA input labeled LFE. In the subs I've seen, the LFE jack is simply a subwoofer input that bypasses the subwoofer's crossover because it assumes that the signal coming into the subwoofer is either the LFE track or a signal that crosses over the low frequency signal content from a 5.1 soundtrack and combines it with the LFE track. Either way, the input going into the sub does not need the crossover.

As far as consumer and commercial LFE goes, I don't think that there's any difference. The biggest difference might simply be that movie theater sound systems typically have full range screen speakers that don't need the kind of bass management that you find with home theater receivers that are designed to work with a variety of speaker setups, including smaller sub/sat systems. I believe that a lot of theater systems use crossover networks in conjunction with the surround arrays, but I don't know what the typical settings are. The LFE channel on a theater sound system goes to their subwoofers. If the bass output sounds louder, that's because movie theaters typically use multiple subwoofers (and often like to set it at a higher level).

[Dmax]

I take this comment back . After lisening to music for hours through the LFE outlet I realize the bass is definitely there but can be quite overlaping as Athena Technologies stated it would ,I tried lowering bass through my receiver but it doesnt sound as good . I guess Athena Technologies know there stuff ,my Polk sub has an LFE outlet and they didnt even render this important information in there manual about LFE not being suitable for music.Shame on Matthew Polk! Go Athena!

[markw]

i.e. no internal crossover is applied Whatever is sent to the sub is what it reproduces. This is great for HT and the LFE track since the receiver (in theory) only sends out the LFE info, no other stuff.

To use this "unfiltered input" successfully for music requires a fairly sophisticated bass management system in the receiver that will take the appropiate actions for a music signal. Not all receivers are created equal in this respect.

[BRANDONH]

I take this comment back . After lisening to music for hours through the LFE outlet I realize the bass is definitely there but can be quite overlaping as Athena Technologies stated it would ,I tried lowering bass through my receiver but it doesnt sound as good . I guess Athena Technologies know there stuff ,my Polk sub has an LFE outlet and they didnt even render this important information in there manual about LFE not being suitable for music.Shame on Matthew Polk! Go Athena!

This has risen my curiosity I like the effects of my sub with movies but dislike the sound with music and often disable the sub on the speaker setting menu for music.
My sub has an LFE and line inputs.
If I do not use the LFE output on my receiver and do not have another Sub output.
What other output could I use?
all my other preouts: Font Left, Font Right, Center, Surround Left, Surround Right, Rear Left, Rear Right are being sent to the amplifiers
Would the tape out be an option for the line level to the sub?

[Dmax]

i.e. no internal crossover is applied Whatever is sent to the sub is what it reproduces. This is great for HT and the LFE track since the receiver (in theory) only sends out the LFE info, no other stuff.

To use this "unfiltered input" successfully for music requires a fairly sophisticated bass management system in the receiver that will take the appropiate actions for a music signal. Not all receivers are created equal in this respect.I've decided to go the recommended route by Athena Technologies.I realize that either way I do it they'll always be something I'll have to adjust depending on the movie or music im using at the moment anyway.Thanx! I saw your set up list, NICE! :)

[shokhead]

.1 Low Frequency Effects
Different then bass.

[shokhead]

This has risen my curiosity I like the effects of my sub with movies but dislike the sound with music and often disable the sub on the speaker setting menu for music.
My sub has an LFE and line inputs.
If I do not use the LFE output on my receiver and do not have another Sub output.
What other output could I use?
all my other preouts: Font Left, Font Right, Center, Surround Left, Surround Right, Rear Left, Rear Right are being sent to the amplifiers
Would the tape out be an option for the line level to the sub?

Has your sub and speakers been setup right?

[BRANDONH]

Has your sub and speakers been setup right?
Yes and it sounds great with movies but I do not care for it much with music.
But what I am asking is if I can use the tape out as an alternative to the LFE output?
Of course I would keep it on LFE for movies.

[markw]

But what I am asking is if I can use the tape out as an alternative to the LFE output?...it passes the signal before any volume controls have been affected. This would really only pass (at full volume, mind you) whatever bass is being passed into and through the analog inputs of your receiver.

[BRANDONH]

...it passes the signal before any volume controls have been affected. This would really only pass (at full volume, mind you) whatever bass is being passed into and through the analog inputs of your receiver.
Thanks and I should have known that, I need wood screws to keep my head on straight.

[Sir Terrence the Terrible]

As far as consumer and commercial LFE goes, I don't think that there's any difference. The biggest difference might simply be that movie theater sound systems typically have full range screen speakers that don't need the kind of bass management that you find with home theater receivers that are designed to work with a variety of speaker setups, including smaller sub/sat systems. I believe that a lot of theater systems use crossover networks in conjunction with the surround arrays, but I don't know what the typical settings are. The LFE channel on a theater sound system goes to their subwoofers. If the bass output sounds louder, that's because movie theaters typically use multiple subwoofers (and often like to set it at a higher level).

Wooch,
Actually the typical screen speaker in a cinema only goes to 40hz(unless you are talking about the screen speakers at Skywalker sound). The typical surround array goes down to 80hz and uses filters to roll off the output below that frequency. The typical surround array in a HPS-4000 system is flat to 50hz and uses no filters below that frequency. They don't need them.