Getting Good Bass for your Home Theater Setup

[Ronildoq]

@boxerfan88

If you have a full-range high-quality LCR, maximize the use of the high-quality speaker by crossing lower, or don’t cross at all. I have the full range Usher LCR that digs down to 30Hz, personally I find crossing at 40Hz works extremely well for me. The remaining speakers crosses at 80Hz.

There are 3 key reasons some do it that way. But in all my test, they do more harm than good

1. The first reason for running full range is because there is lack of understanding integrating mains with subs. Most often, we rely on the EQ programme to do the job, and we just pick a random number to XO, or 80hz . This is not called optimisation, this is picking what most people recommends . Most room eq don’t blend mains with subs

2. Headroom. When the speakers run full range , they are handling bass frequencies down 30hz that requires much more amplifier power. Again the moment you do this, one should look at distortion figures. Unless you listen at -30mv, then you don’t have to worry about distortion or headroom. If headroom is what you are after, full range will not work well. Remember we want the speakers to be cruising, not stressing and handling down Low to 30-40hz. When that happens, what follows is Cabinet resonances , down lower frequencies we no longer hear the direct sound but feel the vibrations. These cabinet vibrations are distortion that are detrimental to midrange and upper frequencies. Some speaker designs are good though

3. The room itself. More often, the room is not controlled. We can easily see that on the spectrogram, using non optimised subs, amplifies that problem. As we saw it previously in a square room. The modes just doubles, creating double the headache in amplitude and null. Hence the decision to go full range.

So yes, there is a myriad of factors behind, if one has problems with the room, headroom, or integration problems, full range can be a consideration. If you don’t face the above, using a dedicated sub will bring your entire system up to another level , always.

Happy to challenge anyone who can localise the subs below 100hz in a well integrated system… I personally can’t, I have integrated many rooms, they are all done using 100hz and they all have excellent decay times below 250ms . Again there is a very big difference between localising bass and directional bass otherwise known as physchoacoustic bass steering… most of the time people get confused with this

[Wechnivag]

Here’s a great article about the importance of multi sub and placement to achieve good bass in room.

AudioKinesis Swarm Subwoofer System - The Absolute Sound

One man’s very subjective view. But the fact that a modest swarm of 4 subs, properly setup and optimised, can best a pair of JL F113, really underscores the dominance of the room influence on the bass sound. It takes a big man to admit that his pair of top dollar high end sub lost out to modest hardware but properly optimized.

Well the good news is there’s nothing stopping him with doing the exact same swarm setup with a Quad of F113

[boxerfan88]

@Ronildoq

@boxerfan88

If you have a full-range high-quality LCR, maximize the use of the high-quality speaker by crossing lower, or don’t cross at all. I have the full range Usher LCR that digs down to 30Hz, personally I find crossing at 40Hz works extremely well for me. The remaining speakers crosses at 80Hz.

There are 3 key reasons some do it that way. But in all my test, they do more harm than good

You have one way. I have my way. Neither is better than the other.

1. The first reason for running full range is because there is lack of understanding integrating mains with subs. Most often, we rely on the EQ programme to do the job, and we just pick a random number to XO, or 80hz . This is not called optimisation, this is picking what most people recommends . Most room eq don’t blend mains with subs

40Hz and 80Hz are multiples of each other. Not that difficult to integrate mains with sub. There are many paths from AMK to Jurong, CTE also can, SLE also can, Lornie Highway also can; not just one path. Who is the one who lacks understanding then? Who is the one who is unable to see the forest for the trees?

2. Headroom. When the speakers run full range , they are handling bass frequencies down 30hz that requires much more amplifier power. Again the moment you do this, one should look at distortion figures. Unless you listen at -30mv, then you don’t have to worry about distortion or headroom. If headroom is what you are after, full range will not work well. Remember we want the speakers to be cruising, not stressing and handling down Low to 30-40hz. When that happens, what follows is Cabinet resonances , down lower frequencies we no longer hear the direct sound but feel the vibrations. These cabinet vibrations are distortion that are detrimental to midrange and upper frequencies. Some speaker designs are good though

LOL. Trying to justify the position with a silly extremes like “listening at -30mV”, then bringing in cabinet resonance/vibrations. Don’t B.S. lah. I supposed my 50kg speaker cabinet is resonating/vibrating so so “much”, and therefore distorting the mid-range to such a micro level, that I can’t hear it, and therefore my ears are…?

A very sensitive 90db/W LR weighing 50kg each, properly anchored to the floor, with 200W amp driving the speakers, can easily provide holographic imaging, beautiful mid-range, and chest thumping bass.

And wow, at LF, human cannot hear direct sound but only feel vibrations. Oh wow! I definitely learn something new today, and all the audio research done over the decades about humans being able to hear down to 20Hz has been debunked today!!!

So are all those research results from universities and research organizations about human hearing range fake?? I wonder if one is mixing up “ability to hear LF direct sound” from “localization/pinpoint LF sound source”??

3. The room itself. More often, the room is not controlled. We can easily see that on the spectrogram, using non optimised subs, amplifies that problem. As we saw it previously in a square room. The modes just doubles, creating double the headache in amplitude and null. Hence the decision to go full range.

It is a indisputable fact that square rooms have double the axial room mode, this is a physical phenomena, no debate there. Having L-R run full range can provide additional bass source to help pressurize the room and even out the bass performance. There are multiple ways to even out the bass response, not just one approach.

So yes, there is a myriad of factors behind, if one has problems with the room, headroom, or integration problems, full range can be a consideration. If you don’t face the above, using a dedicated sub will bring your entire system up to another level , always.

Happy to challenge anyone who can localise the subs below 100hz in a well integrated system… I personally can’t, I have integrated many rooms, they are all done using 100hz and they all have excellent decay times below 250ms . Again there is a very big difference between localising bass and directional bass otherwise known as physchoacoustic bass steering… most of the time people get confused with this

Challenge to localize sub below 100Hz? Hahaha. Using 1 speaker and 1 sub at opposite ends of the room, confirm I can localize the sub until about 50Hz, below 50Hz I cannot. Human hearing is quite solid and can localize bass to quite a low frequency.

In conclusion, I suppose others, me included, are confused, there is only one with clear thinking. LOL.

[Wechnivag]

Chill guys - many roads to Rome. Sometimes it’s stimulating to try and take a different route, a scenic route just to see what’s on the way. Some say it’s the journey, some say its the destination😁

For my next setup, I’m actually going against the norm and planning to run LCR full range. I tried it with my current setup, and found it pleasing.

My main reason is often the bass management is the weakest link in terms of integration, and even with the best crossover, can’t beat no crossover. Caveat being the mains are able to handle the full range signal up to target SPL.

With the best crossover being no crossover, LCR is run large, and the sub is blended in not unlike how 2 ch stereo subs are blended into the mains. There is a low pass on the subs, and a delay to achieve appropriate alignment to sum in phase with the mains…

This should be able to be implemented by most avr.

With traditional bass management I think the evidence is strong that the Diracs and the Lyngdorfs and and the ARCs of the world do a great job in achieving optimal crossover for the bass management.

Audyssey and the majority of the other AVR EQ systems, a bit more hit and miss…

[Ronildoq]

@boxerfan88

confirm I can localize the sub until about 50Hz, below 50Hz I cannot.

Wow, you really are special. I never thought anyone was able to localise bass in a room down to 50hz. Personally I can’t localise them. You have fantastic capabilities indeed

Well done! Come limpeh for u…

At the end of the day, do what matters most to you…

There is a lot of studies out there, one just needs to follow what works best in their room. Whilst I am happy for u that u like to take other paths, that advice don’t really work for the general, especially in a HT environment

There maybe another camp that does full range, that is for music. Where the subs don’t really need to work hard all the time, and down to single digits like HT. That is perfectly fine when there are not that many demanding scenes down lower frequencies

It is a lot easier to talk, show the numbers here, then walk the talk… we can easily tell from the measurements how the room and integration is working and how good the system is . Until we see that numbers, talking is really cheap. Copy and paste from internet is easy to do.

But I supposed don’t have to go there, else this becomes another endless debate.

[Ronildoq]

@Wechnivag

Chill guys - many roads to Rome. Sometimes it’s stimulating to try and take a different route, a scenic route just to see what’s on the way. Some say it’s the journey, some say its the destination😁

For my next setup, I’m actually going against the norm and planning to run LCR full range. I tried it with my current setup, and found it pleasing.

No worries I’m chill. I’ve been there, seen it and done it and I’ve been to top studios toe demo. So I know how a quality set up sounds

That’s good, looking forward to some measurements when tiu have them down the road. Pull out the harmonic distortion numbers down to -10mv. I believe with your skill sets with integration, no issues. But for common folks will be very challenging.

Don’t forget even the DIY speakers in full range, so call full range, but the woofers, mids and tweeter all have a crossover problem to deal with internally

What we do is no different in the sense that we use digital crossovers instead

[Wechnivag]

Also, if the mains are run large, they are additional sources of LF and can contribute to smoothing in room response. Aka swarm. Don’t forget about the vertical direction.

Some of the best bass I’ve heard in an untreated location with no EQ was with a large speaker using dual 15in woofer, one bottom one top head height or higher.

Bryan is enjoying this with the line array woofers

[desray]

@Wechnivag

For my next setup, I’m actually going against the norm and planning to run LCR full range. I tried it with my current setup, and found it pleasing.

My main reason is often the bass management is the weakest link in terms of integration, and even with the best crossover, can’t beat no crossover. Caveat being the mains are able to handle the full range signal up to target SPL.

With the best crossover being no crossover, LCR is run large, and the sub is blended in not unlike how 2 ch stereo subs are blended into the mains. There is a low pass on the subs, and a delay to achieve appropriate alignment to sum in phase with the mains…

This should be able to be implemented by most avr.

Wow…this is definitely going to be an eye-opener since you will be deviating from what the majority is doing now - i.e. set the speakers to small and let the AVR/Pre-Pro handle the bass management. After all, the speaker x-over is not a brick-wall and have a gradual roll-off at certain frequency range. With miniDSP, we can already achieve quite a smooth integration between the mains and the sub(s) albeit like you say not perfect but to most ears, we believe it is already very good and hard to discern.

I can imagine most of the s/w calibration features that deal with bass management will not be engaged except setting a x-over for the various speakers. The LPF for LFE will still remain at 120Hz. I will be curious how well integrated your mains will be with your subwoofers.

[Wechnivag]

@desray

I will be curious how well integrated your mains will be with your subwoofers.

Hi Desray, when you visited, the LR mains were set to large and the center set to small.

Actually after your visit, another golden ear bro pointed out my center didn’t sound right… And I checked the measurements again and realised that the center was actually out of phase with the LR mains.
Something that would have been obvious with bass management as there will be obvious cancellation in the sub crossover between LCR to sub.

No wonder I was getting really drastic differences when comparing center /phantom center, and attributing it to the vast difference in tonality between my center and mains…

Now it sounds very similar when I toggle center on/phantom.

But I digress…

[desray]

@Ronildoq

…I never thought anyone was able to localise bass in a room down to 50hz. Personally I can’t localise them…

Hmm…surprised to know that as well. While I’m no audiophile or professional sound calibrator but my understanding is that beyond 80Hz, bass from the “subwoofer” will become more directional as opposed to its omni-directional characteristics that most of us will want to achieve in our HT setup unless the mains (full range) are able to reproduce what a dedicated subwoofer can do in order to make that happen. I believe Gavin’s next tweak will be able to debunk this audio theory that we have been led to believe.

[desray]

@Wechnivag

Hi Desray, when you visited, the LR mains were set to large and the center set to small.

Oh really? I didn’t even realize that…LoL. What caught my attention is how well you have managed to integrate your speakers with the subwoofers in such a tight space. I didn’t expect you have already did something “out of the extraordinary” back then

Speaking of integration, I believe not just L R but C is also equally important since > 60% of the 5.1/7.1 channel mix comes from LCR as a whole.

[Wechnivag]

Perfect lead in for the topic of this article.

Spaciousness of Bass: Is Stereo Bass a Myth or Reality?

Also in the Audioholics trinnov interview, they talk about rerouting the bass from the surround or atmos channels to the nearest woofer, usually the LCR mains woofer, as opposed to the LFE channel, especially for small surround atmos that need to be crossed 150hz or higher.

Trinnov Altitude Processors: Breaking the 7.1.4 Surround Barrier

[desray]

@Wechnivag

Audioholics trinnov interview, they talk about rerouting the bass from the surround or atmos channels to the nearest woofer, usually the LCR mains woofer, as opposed to the LFE channel, especially for small surround atmos that need to be crossed 150hz or higher.

Trinnov is in another league altogether…Routing bass (however little) to a dedicated subwoofer is indeed impressive! If I have the $$$$$, then I will not need to study all these HT sound theories and how to use miniDSP etc. But one thing is for certain, placement of speakers and subwoofers and the room modes you are in…are something that no amount of $$$$$$ can be expended to get great sound. Not even Trinnov can pull a magic and make a bad speaker/subwoofer placement sound good.

[Ronildoq]

@desray

While I’m no audiophile or professional sound calibrator but my understanding is that beyond 80Hz, bass from the “subwoofer” will become more directional

I’m beginning to suspect that one should be able to localise down to 50hz if the room is small, like 2x3m and the subs are just placed beside you.

That way, there is only one source of energy coming from one area. That may be possible.

Of course if there is only 1 sub and u r playing this in the store room, then we should be able to tell clearly… it’s easier to imagine that way

But to be able to tell exactly if the subs energy are emanating from “x” location down to 50hz is really something special. It is eye opener indeed for me.

Maybe in my set up, my hall is 6x8m, And the subs are all far field placement. For me It is impossible to localise down to 50hz.

This is also the reason why I don’t use nearfield subs, there is a very high risk if done that way

I’m happy to host for a blind test session with x location subwoofer shutdown… to see if anyone can localise down to 50hz…

Don’t need to paiseh, if one is able to do it, I will gladly retract what I have said

In fact I’ve just finished one session today with another member, he told me he is not able to localise the subs, without me asking… lol . He understands directional bass vs localisation. I didn’t even ask him…

[synthesis]

On different perspective, your line array is already stereo and plus other subs at different locations, so it may not matter where you cross. It will be good chance to be non directional. If only one subwoofer is available like in my place, directionality will be more apparent when crossing at higher freq. The room acoustics and layout would also contributes to the directionality.

[boxerfan88]

@Ronildoq

There is a lot of studies out there, one just needs to follow what works best in their room. Whilst I am happy for u that u like to take other paths, that advice don’t really work for the general, especially in a HT environment

There maybe another camp that does full range, that is for music. Where the subs don’t really need to work hard all the time, and down to single digits like HT. That is perfectly fine when there are not that many demanding scenes down lower frequencies

It is a lot easier to talk, show the numbers here, then walk the talk… we can easily tell from the measurements how the room and integration is working and how good the system is . Until we see that numbers, talking is really cheap. Copy and paste from internet is easy to do.

But I supposed don’t have to go there, else this becomes another endless debate.

Hai yah, uncle boxer say there are many ways to do egg fry rice.

“that advice don’t really work for the general” “talking is really cheap” Why so condescending tone and better than thou attitude?? Just because u visited a studio? Doing your setup makes you an expert?

Okay, let me declare, I am not an audiophile, I am not an audio expert, I am just a hobbyist. I am free to share my perspective. I will acknowledge errors if I have stated errors. I have never gone around to brag about studios and such. But to tell a fact, uncle boxer has been to studios, newsrooms, craft editing rooms, audio voiceover rooms, broadcast monitoring and control rooms, in this region and in this country. A few years ago, uncle boxer had the opportunity to attend the presentation/demo/POC of the NHK 8K Super HiVision 22.2 setup at IBC Rai Amsterdam. I can tell you, the 22.2 speaker environment was amazing with solid articulate bass. When they demoed the 8K soccer clip recording with 22.2 audio channels in the demo room, it was like being in the stadium!

To “the general readers”, the assertion is my sharing is considered “advice don’t really work for the general”. My counter to this statement is - “keep an open mind”, “take advice with a pinch of eno salt”, “go visit other setups” and most importantly “chart your own path”.

In conclusion, uncle boxer say “there are many ways to cook delicious egg fry rice”, and “there are many ways to setup an excellent HT system”.

Peace!

[boxerfan88]

@synthesis

On different perspective, your line array is already stereo and plus other subs at different locations, so it may not matter where you cross. It will be good chance to be non directional. If only one subwoofer is available like in my place, directionality will be more apparent when crossing at higher freq. The room acoustics and layout would also contributes to the directionality.

To the general readers, HEAR HEAR!!

[boxerfan88]

@Wechnivag

Chill guys - many roads to Rome. Sometimes it’s stimulating to try and take a different route, a scenic route just to see what’s on the way. Some say it’s the journey, some say its the destination😁

For my next setup, I’m actually going against the norm and planning to run LCR full range. I tried it with my current setup, and found it pleasing.

My main reason is often the bass management is the weakest link in terms of integration, and even with the best crossover, can’t beat no crossover. Caveat being the mains are able to handle the full range signal up to target SPL.

I’d really like to follow your journey. Reason being, a few years ago, I made the shift from standard bass management for similar reasons, and I ended up where I am today.

Do continue to post your findings as you go down this path. I’d love to observe and learn how this arrangement works out for you.

Thank you.

[Ronildoq]

@boxerfan88

Doing your setup makes you an expert?

Uncle, I’m no expert by any means. But I learn things the hard way, first from Jag and then Mark Seaton. These methodology are coming from experts who has been there, seen it done it. And I have been doing this for a number of years now at various rooms for various members in Singapore whenever I can. Not just my room.

I may be a bit too direct with my comments I suppose. Apologies if u felt offended, to me they were all facts backed up by numbers and not hearsay stuff. Nonetheless, I look forward to your contributions to this section in bass management.

Definitely share your journey here, looking forward. By the way which AVR are u using and how do you manage the bass of the rest of your speakers with subs ? Are they all full range?

[Ronildoq]

@synthesis

If only one subwoofer is available like in my place, directionality will be more apparent when crossing at higher freq.

I suppose that makes sense easier to localise with single subs. Were you also able to localise the subwoofer location down to 50hz at your place ?

Higher is definitely possible