Bass Management 101

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[@williamkramer9069]

Matt, I think these types of videos are best. You are the most knowledgeable person making content, and while you aim your services to the higher end, it's us poors that are enthusiasts enough to watch videos on KZbin.

[@davidrivera2165]

Scruffy beard look suits you Matthew. For most HT systems,with multiple subs and in large rooms, setting the crossover of mains and center at 110hz delivers great results (going full range on mains and center with supposedly full range speakers is extremely difficult, Gene being an exception). What is key in this crossover setup is calibrating the gain on all channels to seamlessly integrate with subs. For music 60hz with much lower gain for the subs will likely deliver great results.

[@PIPERBOYWILLIAMS]

best video ive seen on this topic

[@jasonmacarthurdrums]

Always enjoy your content and appreciate the advice.

[@stevenlawrence2232]

Thanks for this Matt. I guess i had always taken the manufacturer -3db point of my 5 1/2 bookshelf surrounds of 63hz as gospel, so therefore used 80hz. Maybe im better off at 100hz? Typically listen at -15 to -18 though so maybe it would be hard to notice.

[@pulDag]

Yeah don't be shy to go higher with XO. Many 80Hz rated home cinema speakers can't hit that with authority.

[@michael-4k4000]

Yea, I tend to agree. But unless you want enormous speakers in your living room. Full range speakers are not really designed for the home. Have Kef Q750, and they claim they get down to 48hz. I use the crossover at 80hz and let the sub do the rest.

[@pulDag]

@@michael-4k4000 it's not about huge speakers but proper design with appropriate drivers. But of course with bigger speakers it is easier.

[@stevenlawrence2232]

All this talk of 1 octave above -3db or tunable speaker frequencies ( after a REW measurement ) for crossover is very interesting for me everyone. My thanks to those that suggested it! I guess I've always been so obsessed with 80hz re localisation I've never considered it really. Just two subs in my case, so not a done deal - but definitely worth trying!

[@mivanp2185]

All set to small I have my front towers to 60hz ,atmos to 110 and surrounds 80. Try and set them about 20 above the lowest response they get. Sounding great.

[@pulDag]

Matt saw Dune recently and definitely fell in love with spice 👀

[@PoesAcoustics]

The Dune movies have absurd levels of bass.

[@fonkenful]

@@PoesAcousticsSo by absurd, you mean almost enough for Gene?

[@RobZelinka]

This is really informative. Thank you for sharing your knowledge and experience

[@KASmonkeys]

Could you kindly talk more about building DIY in-wall baffles and if there is differences between LCR and the rest please. I've seen your other videos but would love to hear more about them. Thanks 😊

[@MegaVH5150]

Always appreciate your content dude. Thanks!

[@PoesAcoustics]

Thank you!

[@poleepwka]

Thanks! I would appreciate your thoughts on the type of EQ and LPFs needed for DIY subwoofers, as this ties in with Bass Management 101. Background: I have four sealed subwoofers using Faital 18XL1800 drivers in 150-liter enclosures. You mentioned that these drivers are among your favorites for meeting various criteria. I’ve been running these without EQ or LPF, relying on Dirac (DLBC or ART) to handle that. However, the low-end output is lacking, rolling off quickly after 30 Hz even with room gain. The infrasonic performance is not as expected, given the size and number of subs. Power is not an issue. The subs, without LPF or PEQ, have output from 16.5 Hz to 2 kHz as measured by Dirac. My Questions: I noticed that most sealed commercial subwoofers limit the output above 200 Hz. For example, Perlisten specs show 15-200 Hz, JTR shows 16-157 Hz, etc. Do you recommend shaping the frequency response before handing the subs over to Dirac? Here’s what I’m considering: Lowering the DSP gain by -8 and boosting 20 Hz by +8, with an LPF at 200 Hz (3rd order Butterworth filter) to control excursion. Applying a 4th order Linkwitz-Riley lowpass at 200 Hz and using PEQ to bring the upper bass down to the same level as 20 Hz. Simulations show that 3 PEQs would flatten the response nicely. How would you suggest I proceed? What form of EQ and lowpass filters would you use? Thank you for your help.

[@PoesAcoustics]

Thank you.I'll answer your question in my upcoming videos

[@michael-4k4000]

Awesome video! Thank you for posting! Please post more!

[@PoesAcoustics]

Thank you! I usually post videos every other day

[@vibeinstalls9890]

Awesome!

[@Tearial311]

I used REW and was shocked that my Arendal 1723THX LCRs needed 100hz crossovers

[@andyv9365]

Thanks Matt!

[@aaronrandolph261]

the problem with trying to explain bass management is no rooms are the same. your equipment may not reflect what is recommended for bass management. if you have large front speakers with large subs or active subs things will likely be different. if your amplifier/receiver does not do bass management in a standard way it can get confusing. some pre amp/receivers dont have a large/small speaker setting or they may have some proprietary setting that does the same thing but is called something else. best thing to do is know your equipment and set your crossovers to what sounds good in your room with your equipment.

[@Saturn2888]

I have all mine at 118Hz crossover. I couldn't go any lower with my Polk R900 heights at volume without them sounding like a car backfiring (popping sounds). Hard to explain. And I put my Ascendos 12 to match. I found that sounded better than 80Hz once I got 4 subs in all corners and couldn't localize the bass as easily. Once I get my Ascendo 10s mounted to the ceiling, I'm hoping I can keep them at 118Hz crossover.

[@user-hn3ic3vz4p]

Ypao always sets all of my speakers to large and bypass the crossover settings so can you show us who to choose the right crossovers using graphs on rew that would be a big help

[@stevenlawrence2232]

@@user-hn3ic3vz4p couldn't agree more but sounds like it's easier said than done...

[@MrBonger88]

Always good to get a refresher on the basics. I prefer to run my dedicated 2ch crossed over at one octave above my -3dB point, which is 32hz , so xover at 64hz. For HT I generally keep everything crossed at 80hz

[@alfonzooliviera1121]

You my dude still dont get it

[@MrBonger88]

@@alfonzooliviera1121I don’t get what I prefer?

[@alfonzooliviera1121]

@@MrBonger88 if you used a mic and REW you'd maybe see that if there are nulls or peaks and you could adjust the XOs to a smoother response and probably your ears would agree but it would highly unlikely you could find it without that.

[@MrBonger88]

@@alfonzooliviera1121when did I say I didn’t use REW? Why do you make assumptions? My preference is based on my REW measurements but somehow “I still don’t get it”

[@alfonzooliviera1121]

@@MrBonger88 why so aggressive? We both know you don't need my approval or permission. And no, you still don't in my opinion

[@tommyaustin4094]

The more subs you are running, the less localizable the lower frequencies, yes?

[@ProfoundAV-123]

I have never liked crossing over my speakers at 80hz. I prefer 40 hz to my dual stacked svs sb 16s three subs per stack. I also have 8 individual subs augmenting each speaker and those subs are also crossed over at 40hz except the wides I cross those at 80hz as I do not have subs augmenting those due to limitation on location. I occasionally switch to all at 80hz but quickly return to my preferred crossover. To me the sound is more dynamic and more enveloping

[@bearclaw5115]

So how many subs are you using in total?

[@ProfoundAV-123]

@@bearclaw5115 I’m using a total of 14 subs which its a combo of 6 svs sb16s stacked, 4 Martin Logan subs two of which are dynamo 1100x and two dynamo. 4 mirage subs one of which is a bps400. I’m using all Martin Logan electrostatic speakers so decided to go with those subs to augment the main towers. However I’m using the bps400 on my center channel whch is a dual 12 and susing a couple of FRX8s to augment the on wall electrostatic speakers. All speakers and subs are crossed over at 40hz to the dual stack. For the wides I’m using Martin Logan motion15 speakers which are not electrostatic speakers but uses the folded motion tweeters, those are crossed over at 80hz as I do not have subs augmented those at the moment

[@jawnauz]

Thanks!

[@PoesAcoustics]

Thank you.I'll answer your question in my upcoming videos

[@pulDag]

@@PoesAcoustics would be interesting topic 😅

[@Gershy13]

As it might be related to this topic, I wonder if there are any real benefits to going with tower speakers for Front LR compared to bookshelf speakers? Other than aesthetics? If we are crossing everything over at 80hz, would it make a difference getting large multi driver towers Vs bookshelf style speakers with similar capabilities?

[@sammy10001]

If you have psedo full range front L , C, R speakers, and a very good gigh power class D amp like purifi model, why not run the front sound stage full range. You can run full range + lfe, or sometjmes called double bass. Then you still have the sub working to cover what the fronts cant do.

[@battousai412]

Emailed you on a Trinnov and last vid.

[@PoesAcoustics]

Hey any chance you could email me again. I apologize. I may have missed it. I tried to search and couldn’t find anything about Trinnov. Sometimes it’s hard to connect a handle with a real person in emails.

[@adresc5391]

Please watch a video on KZbin from a guy called rrel acoustics it's from 2 years ago he talks about the benefits of sending ur receiver to large. So that both your front speakers and your subwoofers get the full range signal I would like your opinion on this

[@mfkhometheater7742]

The AV10 is confusing, in the LFE crossover menu the lowest setting is 80 Hz. In everything else, the lowest is 40 Hz. The AV10 has four independent subwoofer outputs but no manual DSP control over them. I'm currently using one of it's LFE outputs connected to a miniDSP Flex Balanced to control the front and rear subwoofers but I think I'm going to go back to leaving the LFE completely off and just use the external DSP to handle everything. That way I don't have to worry about the AV10 doing anything unexpected. Any reason not to just use the left/right main and extract LFE with the external crossovers? The AV10 has a lot of bass routing options so I can route low end from all channels to the mains.

[@adresc5391]

You mentioned quite a bit about THX what is ur recommendation to set your subwoofer Crossover at?

[@mohammadvasif9335]

Is it advisable to eq speakers an octave below the XO freq before applying the XO and vice versa for the subwoofers .Thanks

[@gabemartinez1012]

Hi, any recommendation on Definitive Technology model BP9040's with the center channel 9040 to use the LFE input or run them large? thanks

[@PoesAcoustics]

LFE in is likely the only way to feed in the LFE signal unless you have no other subs in the system.

[@JohnSmith-qi6co]

I keep seeing Small vs Large completely confusing beginners. Good to see that Denon got rid of the Small/Large terminology int their menus.

[@mivanp2185]

What did they change it to ?

[@JohnSmith-qi6co]

@@mivanp2185 "Full Range" has been added to options in the Crossover menu. You think about what freqs you want to go to which speakers rather than what some noobs perception of a big speaker is.

[@JohnSmith-qi6co]

@@mivanp2185 They added "full" range to the crossover menu. Got rid of the size idea because it confused beginners. No more large vs small.

[@muchirikamau9998]

Is there any advantage to having two or more independent subwoofer outputs from AVRs?

[@PoesAcoustics]

Yes of course. It allows you to ensure each sub is properly time aligned. Which is very important. And if each can be eqed, there are some methods like Soundfield Management that allow special tuning to minimize spatial variation and modal issues.

[@cigarobsession]

In before the correction lol *bass

[@PoesAcoustics]

Oh no! My wife does these. Often she asks me if she spelled it all correctly. This one got missed apparently.

[@nevohraalnavnoj]

$Thanks! Thanks for the great video Matthew. I have a question on speaker choice for a residential home theater. I know you have Perlisten in your home theater, which have a narrow vertical dispersion. It's so narrow on some of the models that I'm concerned all seats won't be covered even with proper aiming. For example, a surround height bookshelf angled down towards MLP may be off 20 degrees vertically for the seat to the left or right. How do you feel about that dispersion pattern versus, say, a coaxial design like Ascendo P5/P6 with a wider dispersion in the vertical direction, and a more similar horizontal versus vertical dispersion overall compared to the Perlistens? Thanks, Jon V.

[@PoesAcoustics]

So I’ve heard this many times and it’s simply not true. I have covered this in past videos. But I think it deserves a new video to explain this better. The vertical dispersion coverage issue is misunderstood. I think some on forums may even knowingly misrepresent this to disparage the speaker. The dispersion angle used for speakers doesn’t mean sound stops outside that angle. It’s a Half angle point. It means the sound is down -6dB in level at that angle. The speaker is around 30 degrees in either direction. Up or down. On the S7T that is true down to 100hz. What happens outside of that range is that the response shelves down and so by 50 degrees it’s around -6 to -9dB. Let’s now assume a two row theater. Let’s assume the theater has a 14” riser and the seats are 6 feet apart. The front row having a 10 foot listening distance to the speaker. If the ear leave is assumed to be 32” off the floor. Then the rear ear level is 46” and let’s assume the speaker is 46”. That’s about 6 degrees down to the first row. That has the same response shape but is down around 1-2dB. Propagation loss is 4dB to the back room. But by favoring the height of the back row we reduced it to just 2dB. And with typical room effects, it would actually be about 0dB at that point. So that narrow vertical directivity actually helps ensure better coverage. Not worse. Now if you aim the LcR at the RSP then sure you would make things worse. But that isn’t a good design practice. This benefit is a common means pros use to get good coverage. And in larger rooms that effect becomes dramatic. For what it’s worth. To be in a situation where it’s vertical directivity Is causing an issue. You would need to be 5’ above the listener. If the seated listener is 3’ and we go to 8’ that’s near or at the ceiling. And that assumes the same distance. In the example I gave, the rear row would need to be 9 feet up to have the same issue. And even then, if it’s above the tweeter access, a small bump appears at 1khz and the hfs smoothly shelve off 6 at 10khz but only 4dB at 1khz. Controlling vertical directivity is actually a valuable way to improve coverage. I think the video that maybe best comes from this question is how a speakers directivity can be used to your advantage.

[@nevohraalnavnoj]

@@PoesAcoustics thanks for all that information! That definitely makes sense. If you wanted to do a video I think that could be great. In particular, if there is a desired response pattern for 2 channel versus home theater. Ie is a wider pattern better for 2 channel but as channel count increases, a tighter pattern is better?

[@PoesAcoustics]

Thank you. I'll answer your question in my upcoming videos

[@kewlbug]

Would you consider a topic on how/what to do if running NO subs? I've recently sold my subs. Towers are Bi amped w plenty of bass (Polk Rti12). I'm having trouble finding the right balance of bass in the system overall especially depending on content. Some is normal, some I have to turn "bass" way down. Ive also gone through the whole different crossover thing in my head trying to sort that out, so this video helps. Considering buying a sub again to set up more typical. Or I may just have to do a consult!

[@fonkenful]

Except for the potential issue that “best” location for transducers producing the lowset couple of octaves found on movie soundtracks - i.e. to well below 20Hz in some cases - don’t necessarily colocate with the higher passbands, particularly in respect to dealing with room modes / standing waves, etc. Ask Matthew and Andrew Grimani what they’d like Gene to give them license to do with the monster towers in his reference system. 😂

[@chebrubin]

Who is using a receiver. A processor and multiple multichannel amplifiers and electrical box switch outlet segregation (dedicated 15 AMP for my Left - Center - Right) is the minimum for quality channel separation. It's not just amplifier power. Channel separation and the ability to drive a speaker at high volumes without signal bleed is so critical to good non fatiguing sound in a 9.x.4 system. I am using smaller speakers from my left, center and right and in-walls and ceilings are best set at the same crossover. XLR cabling is a god send too.

[@fonkenful]

A lot of us are hamstrung to using AVRs as budget processors, with the added benefit of freeing up a few channels of internal amplification for the lower demand height effects when using external amps for the main bed layer.

[@kewlbug]

Is there a DIY test we can do to see if our transition point its higher/lower than 80hz?

[@PoesAcoustics]

It’s really tricky to do this. We are currently debating the topic in CEDIA. Should we tell integrators and DIYers how to measure this themselves or will that encourage people to blow up their speakers? In any case, you could download the M noise test software from Eclipse and measure your speakers. It would make clear where it’s a problem. Another option is the step distortion test in REW. Done at 1 meter in room you may be able to get a valid result that shows the rise in distortion to see at what level this is an issue.

[@kewlbug]

@@PoesAcoustics I suppose the answer's right in front of me. Maybe I expected some technical way. But I'll prob get in REW and run different band limited noises or even just sines.. I'm guessing I will learn a lot about my room. I'll have to look more into M noise.

[@andyv9365]

Is that why pioneer only uses a mono xover?

[@PoesAcoustics]

What do you mean by mono crossover?

[@andyv9365]

@@PoesAcoustics sorry , I mean there is only one crossover setting for all channels .

[@bearclaw5115]

@@andyv9365 I think that's just laziness on Pioneer's part. My Marantz 8015 drives me nuts because it only offers 20hz steps in the crossover (60,80,100hz). Like, is it that hard to offer 10 or 5hz jumps?

[@muffinviking]

it's spelled bas.

[@kewlbug]

got Base?

[@Zachary_Setzer]

All about that base.

[@PoesAcoustics]

😓

[@fonkenful]

No treble