Who doesn't use Bass Management?

[o0O Bill O0o]

Since 5.1 or Multi-channel audio has full-range channels and a LFE channel, Who chooses to run full range speakers for each channel and a subwoofer(s) for LFE?

OR subwoofers for each channel, i.e. 5.1 would have 6 or more subs, one sub for each channel ( line level or pre out ) plus however many for the LFE channel-- treating each channel as a 3 or 4 way speaker.

Cost-effectively 5 small speakers with bass management to a subwoofer that has to play bass and the LFE channel works.. but wouldn't electing NOT to use bass management capture a greater effect of sound reproduction?

[jomari]

i tried to re-read this posting over and over again, so hopefully i get to answer it properly,

Since 5.1 or Multi-channel audio has full-range channels and a LFE channel, Who chooses to run full range speakers for each channel and a subwoofer(s) for LFE?

i dont think a number of people here choose to do so, considering sending a full-range signal to some of the speaker, at certain listening levels would damage them due to its capabilities.

OR subwoofers for each channel, i.e. 5.1 would have 6 or more subs, one sub for each channel ( line level or pre out ) plus however many for the LFE channel-- treating each channel as a 3 or 4 way speaker.

i got lost here. so, what you're saying is someone experimenting with a subwoofer for each speaker, ie, front left (with sub1), front center (sub 2), front right (sub 3) and so on, correct? i will expound later in my posting...

Cost-effectively 5 small speakers with bass management to a subwoofer that has to play bass and the LFE channel works.. but wouldn't electing NOT to use bass management capture a greater effect of sound reproduction?

the reason why we implement bass management would be
- the speakers at certain levels would not be capable of reproducing the sound needed at lower frequencies,
- the subwoofers sole responsibility is to reproduce the lower extension of the material, relieving the avr of its duties, and giving headroom for it (the avr) to perform much better, focused on the 5 other speakers
- the main reason why bass management is so important is to have one source to reproduce the lower frequencies. unlike the higher frequencies, the lower extension has longer soundwaves, which can interact incessantly with the enclosed environment, building up in certain areas, and at times, have certain 'blind' spots, where bass is less prominent or uneven. if we have multiple sources for it, we'd end up with cancellations, or in some cases uneven responses, all in all, a poor result.

think of it this way, think of a HT room, with the floor flooded with water, about three inches deep.

The separate speakers, will be reproducing smaller waves, which dissipates to the room with little or minor challenges that can be addressed with panels to minimize its reflectiveness.

The LFE signals would tho be producing larger, more separated waves, and at times, will cumulate at the corners of the rooms (thus bass traps to address them).

Now imagine having multiple big waves being reproduced by ALL the speakers and/or from the subwoofers connected to them. To address both these situations, would be a headache to deal with, and well, im not even certain we can address.

Just remember that the speakers are only a component in the home theater room we have, and that a rooms influence on the sound is also a big factor to consider, thus my emphasis on room treatments as a huge investment to consider.

[crazyBLUE]

Nice post jamari ! You make sense out of ~

[ryandubbz]

Originally Posted by crazyBLUE

Nice post jamari ! You make sense out of ~

LOL I was thinking the same thing

[jomari]

i had to come back with a bang folks...

this is one reason why im still 'the other guy'.

[o0O Bill O0o]

Originally Posted by jomari

the reason why we implement bass management would be
- the speakers at certain levels would not be capable of reproducing the sound needed at lower frequencies,
- the subwoofers sole responsibility is to reproduce the lower extension of the material, relieving the avr of its duties, and giving headroom for it (the avr) to perform much better, focused on the 5 other speakers
- the main reason why bass management is so important is to have one source to reproduce the lower frequencies. unlike the higher frequencies, the lower extension has longer soundwaves, which can interact incessantly with the enclosed environment, building up in certain areas, and at times, have certain 'blind' spots, where bass is less prominent or uneven. if we have multiple sources for it, we'd end up with cancellations, or in some cases uneven responses, all in all, a poor result.

Ok, what if you had speakers that can play low bass? Most recording engineers are directed to send low bass to ALL channels and keep LFE specifically for Low Frequency Effects. (reference the forum sticky) Recording Engineers/ Dub-stage mixers have full-range control/ dub-stage monitors and a set of subwoofers for LFE.

BUT By using subwoofers connected to the pre outs/speaker level of each channel, you preserve the low frequencies for each channel that the speaker cannot produce, and you can better integrate the subwoofer with the speakers via the subs low/high pass filter. This is not the preferred method, I could go on about how each crossover is designed specifically for each speaker in the system and trusting Bassmanagement filters or even a subs high pass/low pass filters to integrate seamlessly seems like crap shoot.


In my findings the Studio doesn't use Bass management in establishing a disc soundtrack. However since most of us listen to playback on consumer gear, the soundtrack is validated on a bass-managed audio system to ensure that the bass translates properly to consumer gear.

I am looking for users who adopt the standards of playback that the recording studios use.

Standards are set forth in AES, SMTPE, and ITU papers referenced in the .pdf file on this thread

Hope this helps explain my question.

[jomari]

Originally Posted by o0O Bill O0o

Ok, what if you had speakers that can play low bass? Most recording engineers are directed to send low bass to ALL channels and keep LFE specifically for Low Frequency Effects. (reference the forum sticky) Recording Engineers/ Dub-stage mixers have full-range control/ dub-stage monitors and a set of subwoofers for LFE.

BUT By using subwoofers connected to the pre outs/speaker level of each channel, you preserve the low frequencies for each channel that the speaker cannot produce, and you can better integrate the subwoofer with the speakers via the subs low/high pass filter. This is not the preferred method, I could go on about how each crossover is designed specifically for each speaker in the system and trusting Bassmanagement filters or even a subs high pass/low pass filters to integrate seamlessly seems like crap shoot.

Good question nonetheless, ive also liked reading that pdf file from time to time, as a refresher as to reinforce my stance. ive declined from replying at the thread because of a number of opinions towards it. I do appreciate a great conversation tho from time to time. We do also have to consider that this article was originally written in 2004, albeit dated, it STILL works, aside from certain nuances.

I will address this in two folds,

First situation is using speakers that can handle lower frequencies, better yet significantly reproduce them at higher volumes, by all means, its acceptable, as long as we've properly calibrated our systems, and acoustically treat said listening area. by all means, im not asking you to re-create an anachoeic chamber, but i am hoping for at least some assertive measures to minimize room interaction.

In regards to the setup of the room, they've specifically informed us of critical points needed to acheive bliss via notes posted in the beginning of the document. (bulletpoints start at page 7).

One very important aspect discussed here, was the fact that this article was written with Engineers in mind, and difficult for more more commonfolk would comprehend, or even use in their environment.

In my findings the Studio doesn't use Bass management in establishing a disc soundtrack. However since most of us listen to playback on consumer gear, the soundtrack is validated on a bass-managed audio system to ensure that the bass translates properly to consumer gear.

I am looking for users who adopt the standards of playback that the recording studios use.

Standards are set forth in AES, SMTPE, and ITU papers referenced in the .pdf file on this thread

Hope this helps explain my question.

As ideal as it would be, i wish my setup would be as clear cut as these setups would, but unfortunately, the challenge is that i also use this as a living space as well. thus the compromise.

Sorry, been busy at work right now... will contemplate further on this if you dont mind.

Great topic by the way....

*edit*

Theyve mentioned a brief description of what full speakers are, defining them as speakers that can handle 18hz or lower, thus a tad on the contradiction. To MIX materials (as im not an engineer, i cannot comment completely on it), they consider this as an absolute must. but as a source or to listen to material, then id have to disagree. There are a limited number of speakers that can fit that bill, and id rather have the subwoofer pull the hard work, and as ive mentioned previously, let the LFE or lower frequencies emenate from one source/access point instead of multiple areas. (we can get into the two, four, six sub setups later )

[DIGITALBATH]

I have a confession to make. I made an error that is very pertinent to this post. I've been suffering from poor crossover settings in which I chose full on my front towers Paradigm Monitor 7 ver4.

I always tweak my settings, but I remembered the guy from Definitive Audio where I bought them said play them on full. They only go to 54hz. So I had my sub 80hz, the fronts on full and center and satelites at either 120-150.

I can now concur that the fronts were battling with my sub for the good meaty bass, and the was a loss of accurate bass production. I since I have set the fronts to 80hz. The system is much better now. I also usually listen to audio on surround, so this suits my needs better. Never stop tweaking, adjusting, checking specs. The day we do is the day we die.

[o0O Bill O0o]

Jomari, I think the makers of Audio Doctrine haven't made or made public updated whitepapers that elaborate that Bass Management is actually better.

I was looking for end-users who swear that NOT to bass-manage was the best route to go... Since I have not found any documents saying that bass management was the way to go.

Still, Thiel Audio uses there own crossover in the SCS4 Hometheater system, claiming that crossovers are designed specifically for they loudspeakers and their enclosures and casts "Why would you trust a generic (not specific to the loudspeaker/enclosure design) crossover used in your Bass Managed A/V Receiver?"

So they still bass manage, just use there own crossover. You set your Mains to Large and subwoofer to "off" or "none". Also, if there is a LARGE+LFE Setting, ensure that is "on" for the mains. The crossover sends high pass signals to the SCS4 mains and Low pass to the Thiel Smart Sub. The center and surround use the crossover setting in your receivers bass management, which is often 80Hz.

[Big Daddy]

If you have a capable subwoofer or multiple subwoofers in the room, all your speakers become SMALL by default. This has absolutely nothing to do with the physical size of your speakers or the low frequency extension of your front or surround speakers. It has everything to do with the source of bass waves in the room and their interaction with the room boundaries. In most cases, you do not have that much flexibility with the placement of the front or surround speakers. However, a subwoofer can be placed almost anywhere out of the way for the most optimum bass sound. The low frequency extension of my front speakers is 14Hz and I still set them to small and use bass management. The strategically placed subwoofers in my room can do a much better job of creating bass sound.

Originally Posted by o0O Bill O0o

Since I have not found any documents saying that bass management was the way to go.

I am surprised that you made that statement. The most important research about speakers and subwoofers have been performed by Dr. Floyd Toole and his associates (Sean Olive, Allan Devantier, Todd Welti, etc.) at the National Research Council of Canada (NRC) and at Harman International. They did multiple studies in anechoic chambers and real rooms to study the behavior of low frequency waves. They also ran many simulation models. One of the most important things that they found (that is quite contrary to the people who propose and promote full-range speakers all around the room) was that when all your speakers are running full-range in the room, you will experience a huge difference in the level of bass that is generated by each speaker. It is best to quote Dr. Toole from one of his scientific articles.

http://www.harman.com/EN-US/OurCompa...ndRoomsPt3.pdf

When a full-range signal is panned to each of the loudspeakers in turn, and measurements are made at the listening position, we find hugely different bass responses for each of the loudspeakers. The differences are a large as 40dB in this room, and the biggest ones are all at low frequencies. The reason, the woofers each have very different acoustical “coupling” to the room resonances because they are in different locations. This will be different for every different room. Again, referring back to the “circle of confusion” the bass that was heard in the control room will not be the same as that heard at home. It cannot be.

BassManagement.jpg
We have five very different bass sounds, one for each channel!

Attempting to improve the situation by panning the bass to pairs of loudspeakers changes things, but does not remove the problem. Anybody think that an “ideal” room can help this? An anechoic room would, but none of us would wish to live in one.

And this is why bass management and subwoofers make sense. Now we can place the woofers where they perform optimally for a specific room with a specific listening position. We can place the satellites (a term that seems inappropriate for some of the large capable loudspeakers that we use in the high-passed channels) where they need to be for directional and imaging effects. In other words, we design the low-frequency portion of the system separately because rooms force us to do so. This is the only way that we can get good bass in any room, and have any hope of having similarly good bass in different rooms. Remember about preserving the art?

[o0O Bill O0o]

Big Daddy, Wow, great response! This is what I was looking for.

I was un-able to find the documents and the research that has done, so I resorted to the "easy button" and asked the question on the forums.

[Fors*]

Originally Posted by o0O Bill O0o

Big Daddy, Wow, great response! This is what I was looking for.

I was un-able to find the documents and the research that has done, so I resorted to the "easy button" and asked the question on the forums.

Get used to Big Daddy providing tons of helpful info.....he is referred to "The Oracle" or other comparable names when it comes to audio.

[crazyBLUE]

Originally Posted by Fors*

Get used to Big Daddy providing tons of helpful info.....he is referred to "The Oracle" or other comparable names when it comes to audio.

Big
Daddy

=

[Fors*]

Originally Posted by crazyBLUE

Big
Daddy

=

That is a great one crazy...love those smileys!

[crazyBLUE]

Originally Posted by Fors*

That is a great one crazy...love those smileys!

Thanks Fors

Big Daddy is the King of Bass & & & & & & & & & & should I go on

[dobyblue]

The only time I skip bass management is when I'm listening to SACD's...because to apply bass management would force me to implement a DSD>PCM conversion. My speakers are all full range and I find keeping the DSD chain through to the analog stage has given me what I feel is the best sonic signature. I simply use the crossover on my sub with DSD signals to limit the sub to around 50~60Hz as I don’t want to hear sonic info higher up coming from the sub.

I use the individual level settings to even out the sound, although I’m fairly equidistant from all five speakers in my 5.1 array.

At all other times I’m using bass management with my fronts and rears set to 60Hz and centre set to 80Hz. This seems to provide a more powerful and articulate bass response in my room for all other multi-channel sources.

[jomari]

ive actually indicated most of the details found in the harmon report indicated by big daddy previously, stating...

Originally Posted by jomari

- the main reason why bass management is so important is to have one source to reproduce the lower frequencies. unlike the higher frequencies, the lower extension has longer soundwaves, which can interact incessantly with the enclosed environment, building up in certain areas, and at times, have certain 'blind' spots, where bass is less prominent or uneven. if we have multiple sources for it, we'd end up with cancellations, or in some cases uneven responses, all in all, a poor result.

think of it this way, think of a HT room, with the floor flooded with water, about three inches deep.

The separate speakers, will be reproducing smaller waves, which dissipates to the room with little or minor challenges that can be addressed with panels to minimize its reflectiveness.

The LFE signals would tho be producing larger, more separated waves, and at times, will cumulate at the corners of the rooms (thus bass traps to address them).

Now imagine having multiple big waves being reproduced by ALL the speakers and/or from the subwoofers connected to them. To address both these situations, would be a headache to deal with, and well, im not even certain we can address.

Just remember that the speakers are only a component in the home theater room we have, and that a rooms influence on the sound is also a big factor to consider, thus my emphasis on room treatments as a huge investment to consider.

Prior to responding, ive seen big daddy has posted his findings (which was always in his initial posting at the bass management sticky thread, and indicated it further with a valid source (as posted earlier, the harmon report), which has been used countless times, as reference as to why we need bass management.

I was looking for end-users who swear that NOT to bass-manage was the best route to go... Since I have not found any documents saying that bass management was the way to go.

im not quite certain if you'd find many, aside from those who use SACD or dvd-audio as doby has mentioned.

The only time I skip bass management is when I'm listening to SACD's...because to apply bass management would force me to implement a DSD>PCM conversion. My speakers are all full range and I find keeping the DSD chain through to the analog stage has given me what I feel is the best sonic signature. I simply use the crossover on my sub with DSD signals to limit the sub to around 50~60Hz as I don’t want to hear sonic info higher up coming from the sub.

I use the individual level settings to even out the sound, although I’m fairly equidistant from all five speakers in my 5.1 array.

At all other times I’m using bass management with my fronts and rears set to 60Hz and centre set to 80Hz. This seems to provide a more powerful and articulate bass response in my room for all other multi-channel sources.

The only reason why is because at one point or another, the sound reproduced by the higher def audio format can (albeit very limited), reach a lot lower than normal 'movie' or 'artificial listening - (using dsp's for example or matrixing them), thus the preference for a lower crossover setting.

Still, Thiel Audio uses there own crossover in the SCS4 Hometheater system, claiming that crossovers are designed specifically for they loudspeakers and their enclosures and casts "Why would you trust a generic (not specific to the loudspeaker/enclosure design) crossover used in your Bass Managed A/V Receiver?"

So they still bass manage, just use there own crossover. You set your Mains to Large and subwoofer to "off" or "none". Also, if there is a LARGE+LFE Setting, ensure that is "on" for the mains. The crossover sends high pass signals to the SCS4 mains and Low pass to the Thiel Smart Sub. The center and surround use the crossover setting in your receivers bass management, which is often 80Hz.

valid remark my friend, and a very good one. but i believe that with thiels document, it still encourages the use of independent crossovers were to be used, as well as an external one if im not mistaken. The article simply indicates what can be done by two components, which is, quite honestly the same thing with using bass management in the first place. to put it bluntly, they took the long route to get to the same destination.

i guess it takes big daddy to validate your point.

Now, aside from the article, your quest to find those who prefer using large or even LFE+main, will be quite limited friend. Im not certain if we can find someone who might be willing to go down this path for a number of reasons, mostly two:

1. cost
2. technical background.

to reproduce the sound in a way where the full range would be used in all speakers (better yet, lets go back to your previous example, using front left with sub, front right with sub, etc), will be a good starting point.

Compare it to a cars, and its ultimate goal, reaching a certain speed, lets say mach 1.

You'd have to have a very good car to handle such (the speaker)
The signal should be strong enough to reach that speed (the signal),
To get there, there are a expletive amount of details:
- can the engine handle it?
- the perfect road where the car shall drive on
- wind, environment conditions?
and so on...

it IS doable, just very expensive, and of course, you need three guys in a lab coat to verify everything. Plus the emt squad. and chuck norris.

going back to speakers, its almost the same thing,

spend a good amount of money to reproduce these sounds with
- qualifying speakers,
- qualifying amps
- the signal.

now, we double this expensive route treating the room to reproduce it,
- acoustic treatments,
- countless calibrations
- testing room variations

all to accomplish not only a flat response, but to also address having 'the perfect signal'.

sure, you can cheap out and just do so, but you wont get the ideal nirvana you're looking for, if you dont do it properly.

or we simplify things by,
limiting the signal to one source,
acoustically treat the room,
fine tuning the details using an spl meter, and a trusty software to help (like TruRTA)

two paths, one goal.

just an insight.

[o0O Bill O0o]

If I had to sum this thread up:

If you have a <30,000 cu ft room, run bass management.

Multiple subwoofers is best.

and don't dare that your missing out on that last 50-60 cycles below 80hz, when using BM,from ANY of your speakers in your room. They, the speakers, don't need it anyway.

[dobyblue]

Originally Posted by o0O Bill O0o

If I had to sum this thread up:

If you have a <30,000 cu ft room, run bass management.

Multiple subwoofers is best.

and don't dare that your missing out on that last 50-60 cycles below 80hz, when using BM,from ANY of your speakers in your room. They, the speakers, don't need it anyway.

That totally ignores the DSD issue though.

[o0O Bill O0o]

Originally Posted by dobyblue

That totally ignores the DSD issue though.

You mean running 6 channel straight from your SACD Player?

Right now, I believe the DSD format is marginalized. Most consumers are directed to convert to LPCM and then run Bass Management.

Otherwise, use active or passive crossovers between the SACD player and the 6 channel input of what ever you connect it too.

I just connect my SACD capable player (PS3&OPPO BD-83) via HDMI, convert to LPCM, to the back of the Receiver(Yamaha RX-V1900) and use the music setting (+10db on Sub pre out) that I was able to configure. the SACD sounds like it was supposed to. No quiet bass.

Maybe some processors decode DSD and properly bass manage? but what a pain.

What about LFE? -10dB?