It would be really nice if you could show us some real world examples of how you design a room, especially if you could go in to detail of how and why you designed your own home theater

Hello Matthew, I find these types of videos the most interesting. Being an engineer though I like the numbers! The 10-15% absorption and 15-20% diffusion makes my ears prick up because I can work out the specifics for my space, even if as you said it’s just a starting point. So please, the rules of thumb are great to give an idea, but for those that like the maths, can you flash up the formulas where they exist? Please keep videos on room acoustics coming! Thank you.

@PoesAcoustics

4 ай бұрын

We could do a deeper dive. The 15% rule is really not a technical rule. It's more like a generlization that makes for an easy starting place. For what it's worth, Anthony and I both had this idea that we felt it didn't make sense to always do carpet on the floor. That a ring or U shaped solid floor perimiter would help keep some floor absorption while also reducing the amount of absorption on the floor (which isn't really desirable). We implemented, as standard, the U ring of solid floor in all our designs recently. The net effect is we are often now adding 18% or so of absorption to most of those rooms. And I tell that just to point out that these rules can't be tied back to formulas. it's more about how much absorption area most rooms tend to have and how much needs to be added to hit common targets as a ratio of total room area. But if you reduce fixed absorption area, like we did, then the ratio needs to change again.

Amazing video Matt ! You really explain things well ! You are an incredible asset to the hobby and to the community 🙏

@PoesAcoustics

4 ай бұрын

I really appreciate that and the donation. Thank you!

Great lesson/summary about absorbtion and diffusion, thanks for it Matt.

excellent info Matt! always enjoy your viewpoint

@PoesAcoustics

4 ай бұрын

Thank you, I appreciate the feedback.

Great discussion, Matt. I could see ALL of this at play in the design ideas we’ve reviewed recently.

@PoesAcoustics

4 ай бұрын

Thanks Omar. Absolutely. The way I work professionally stems from my core philosophies on sound reproduction. I don't mind sharing those here.

Thanks!

@PoesAcoustics

4 ай бұрын

Thank you! Glad you appreciated the video.

This is really helpful, thanks and timely as I am currently in the design stage for my home cinema update.

@PoesAcoustics

4 ай бұрын

Glad it was helpful!

Matt, please make a video on your services. Your site has descriptions, but a short video presentation with examples could be a great advertisement for your business.

@PoesAcoustics

4 ай бұрын

Good suggestion. I've raised it with Anthony and will work on putting something together that highlights my services and what they look like. I think that is actually a great idea.

Tested diffusing on side walls with concrete forming tubes cut in half mixed with diffusion. Big improvement in room size. Thanks for video.

@PoesAcoustics

4 ай бұрын

Yes a half cylinder diffuser actually works surprisingly well. While its not as technical of a product as a QRD type diffuser, the actual effect on scattering is massive and there is clear evidence of phase mixing, even if its not as good as a QRD. For such a simple device, they work so well.

@56ctconger

3 ай бұрын

I use 12” whole cylinders stuffed with fiberglass and covered with a stretch sock of fabric. They are elevated several inches off the ground to allow LF to enter the fiberglass inside. With (2) 5’ cylinders on each side iI get both some bass absorption as well as HF diffusion.

There is a bit of an art to this. In the end, there is a lot of science, but there is a lot of art. It comes down to making a room sound right. Great job on the video matt, as always!

@PoesAcoustics

4 ай бұрын

thanks! And for sure there is art. We don't really know what sounds "best" and likely even if we did, there would be margin around that. So treating it as an art makes sense. Plus...It's your system. You have to enjoy it.

Good informative video

Really like the new video setup you have. Much easier to watch, more balanced. As to the content, a very nice overview. I would love to pick nits about side wall absorption a little. So many folks are placing their left and right speaker within inched of the side wall, and frankly, that places the first reflection point for almost all listeners right there on the wall next to the speaker.......and killing that immediate reflection really seems to clear up the sound stage, especially for speakers that don't have good directivity (ie, most of them on the market!).

@PoesAcoustics

4 ай бұрын

Yeah that is a pretty specialized scenario. Really speakers shouldn't be that close to a wall.

@nattydj8646

4 ай бұрын

@@PoesAcoustics agreed but I see it all the time :)

Really love your videos! I am doing some of the same work in Norway, but not on your level. Your videos make me think about new alternatives to some problems, and you also have a great way of explaining why. This might be to into your "paid knowledge" but an interesting video would be to discuss what type of diffusion in what location. And also the preferred bandwidth for those. I think this is a field where the knowledge is poor, even for myself. Hope your business is going strong!

I like movies with very good soundtracks as well as listening to music (The Rolling Stones, Pavorotti, etc. & Bohemian Rhapsody, Highlander, etc.)

How do you approach a HT area that has no backwall (open to another use)? I can only book absorption on side walls and absorbtion/difuser on front wall.

I have fabric blinds & curtians on both windows (small/large) on side walls from LCR in the middle. 65" TV on a glass stand. Two sofas in room (2-3 seater) fully carpeted with thick under lay on ceiling large LED light with crystals . There is coffe table and a small lamp/table on side. Where are my "first reflection absorbers and first reflections" ? and other decrotive peieces...

Great video as always! Since watching your videos I'm removed a lot of treatment from my over treated space. I've now got almost no absorption on the walls and just diffusion panels. In a room 5.5x4.5x2.2m I'm still struggling to get the RT60 about 200ms. It sounds great but I'm sure it could be better. The space behind my AT screen is heavily dampened with rockwool so I either need to turn this into a baffle wall or cover some parts with a harder surface perhaps.

@PoesAcoustics

4 ай бұрын

That is a really common problem. It's one reason why I've become more careful with how I treat the front screen walls. In some rooms, treating the area behind the screen like you indicate can lead to a room whose RT time can't be sufficiently high.

First of all, your production quality is a million times better! Great job! :) For music listening, aren't most control rooms pretty dead? For me, the best listening experience is sitting in front of some really nice near-field studio monitors in a dead room. I want to hear the mix, not my room. Maybe as an audio engineer, I hear music differently than most people. However, for movies at home, I agree 100% that the room needs to breath. But, the few times I've been a post production stage, those rooms are pretty dead too. Maybe it works on post stages and movie theaters because there are so many surround speakers. Or are those rooms not really dead, but they just feel that way because I'm expecting such large rooms to sound like a cathedral? You stuff is golden! I am in the process of building a new theater space with a ton of compromises, and you are helping me navigate my way through it.

Matt, thanks for all the videos and for putting extra effort into production. Would love to see a video on the “shoebox side surround” scenario as I have a 13’ wide room with a pretty wide couch as the seating. Side surrounds at 90 degrees were too close even for a listener in the center of the couch, and due to a door I had to jump all the way back to 30 degrees behind MLP for my side surrounds.

@PoesAcoustics

4 ай бұрын

Hmm yeah, those are always tough. Personally, I probably would have raised the side surrounds up higher. But often you do what you have to do with the room you have.

@dmessent

4 ай бұрын

@@PoesAcoustics thanks, maybe I will play with that some more. Thankfully I’m using on-walls (revel s16) so experimentation is cheap. Related, does speaker design play at all into localizability at these distances or will all good designs perform about the same?

@dmessent

4 ай бұрын

I ask because the genelec 8010s on my desk have a super strong center even though they are just a couple feet away.

@PoesAcoustics

4 ай бұрын

@@dmessent I wouldn’t expect a strong rear wall first reflection to impact center image. It would be other aspects of spaciousness and envelopment.

Light is much better! Great backdrop being all centered, my OCD is happy

@PoesAcoustics

4 ай бұрын

Thanks Nikita. Yeah I did better on this one for sure.

Mr. Poes, You mentioned the lack of quality mixed Atmos movies. I am always looking for reference material to play in order to find out how far away from good my budget HT system is. Do you have any suggestions for a "reference" quality movie/demo and a source for it? Thanks a million and I wish you and yours all the very best, Kevin

What are your thoughts on the effectiveness of adding strips of FSK foil tape to existing panels as a budget-conscious way to prevent or reverse overabsorption of higher frequencies?

@PoesAcoustics

4 ай бұрын

Sure that can work.

Hi Matt - great video. Do you have any thoughts on rooms designed around the concept of non-environment and FTB rooms (i.e. hard front wall and floor for comfort, deep absorption everywhere else?) Or do you take the stance that such rooms are simply not practical, or perhaps you would still hang your hat on envelpment /spaciousness?

Ugh. I have some plans on my ceiling and was looking for guidance on that aspect. Then you finished with a cliffhanger. Lol 😅

With the approach of getting the absorption in to get the right balance of reverb in the rooms, is there a minimum thickness of panel you will use?

Gr8 video Matt. Is it possible that treating 1st reflections may sometimes make certain type of dispersion speakers little lifeless?

@PoesAcoustics

4 ай бұрын

I suppose. I think the term lifeless is so general that it would be hard to know. It wont impact the dynamics, but it would impact the image width.

Great video 😎 If you had a room with the MLP only 12 - 18” from a solid back wall would you always absorb behind there? (As it would be quite close to any diffusion) (5.2.4 setup)

@PoesAcoustics

4 ай бұрын

Generally yes, but I might put a GUD diffuser toward the outside of the seating area. I haven't played with the GUD's that close much, but plan to try them. The developer has indicated that their nearfield to farfield transition is less than 12 inches, likely closer to 6". It's a really efficient diffuser and so it's only 2" deep (less really) but works well down to around 1khz. In theory such a product could be used behind your head. I would be interested to try it. I don't love absorbing behind my head, but you often have to in scenarios like you mention.

@pauledwards8721

4 ай бұрын

@@PoesAcoustics Thank you, searching that product now.

Matt, what is your opinion on black birds recording studio where they have a room that is pure diffuser, 2d, skyline type. Its a music and atmos music recording studio.

@PoesAcoustics

4 ай бұрын

I'm quite familar. I don't know that I have a strong opinion. It's a really unique idea. Create a room that is acoustically a purely gauzian room is really interesting. It sounds like a great idea. Anecdotely I've heard the room isn't very popular amongst artists/mixers and that its move to a multichannel mixing room stemmed from looking to revitalize the room and get it back in use. I don't know if there is any truth to that, or if they would ever admit it if it were true. What I can say is, nobody else has ever done that since. Which may be for good reason. The technical reasons for why that may be good or not is beyond what I can comment on here but maybe could be a good topic for a diffusion video.

So if you have a decently long room 23' but the width is extremely narrow 11' to 12'. Would it be best to have the seating and surrounds in the widest part or would it's still very narrow width make any real difference? I know this would mean a smaller screen but would it sound better with that little extra space the side surrounds would be? The room was 2 roughly square rooms before taking the middle wall out. Ceiling is also only 8'. Thought 2 rows of 2 would be about the most possible there? Just worried about how narrow the room is and the placement of surrounds. Would the wider part of the room be best used for screen size or make a difference with the surrounds from the listeners?

Would shooting 1w and measuring at the listening position with the right calculations be able to determine if there is too much or too little reflection given the resulting volume knowing the distance, 1w and speaker sensitivity?

@PoesAcoustics

4 ай бұрын

I appologize, I am not totally sure what you are asking. To understand the room reflections, the volume of the speaker, it's sensitivity, and the power its given is irrelevant. We can look at the reflections by looking at the ETC, Wavelets, etc. The volume simply needs to be loud enough that the impulse response measurement can resolve signal and not just noise.

@njrumenos

4 ай бұрын

@@PoesAcoustics ok I thought that maybe a bright room would increase the overall volume measured, I am still learning about room acoustics, it truly is an interesting topic

I prefer a more anechoic movie room and a more spacious room for 2 channel. I figured this out by trying to combine in one room and just couldn't combine the 2.

great video again clarifying things. could you do a video on near field effects? as i understand it a lot of studio monitors are placed such that they would be effected, does that effect the mixes?

@PoesAcoustics

4 ай бұрын

Nearfield monitoring is a particular approach in which the monitor is placed so close to the mixer that you largely only hear nearfield content, no room. The direct to reflected ratio is extremly high. It's not an approach you should use in a home and it's not intended to sound better or real. It's a means of putting a microscope on the mix.

@niklasxl

4 ай бұрын

@@PoesAcousticsoh interesting, so most stereo desk setups will sound slightly unnatural or does it not really matter that much in that context that the speakers are too close?

@PoesAcoustics

4 ай бұрын

@@niklasxl the speakers aren’t problematic so close. Nearfield monitors are designed to transition to their acoustic farfield within 6-12 inches. The nearfield playback just causes very high direct sound to reflected sound ratios. So there are virtually no acoustic room cues. A lack of spaciousness and envelopment. Poor depth. Narrow apparent source width. Things like that. Which for what they are doing are all unimportant. They are listening for errors in the recording. The balance of instruments. Weird noises. Things that might be masked in a proper listening environment.

@niklasxl

4 ай бұрын

@@PoesAcoustics i see, i was more thinking with the second comment about consuming (not creating) media in front of the computer, should the goal there be to get the speakers a bit further away then directly next to you display? another question: are closed vs open back headphones and nearfield vs not at all related (headphone speakers ofc are always very close) or do they just have some similar effects?

13:32 60-deges is on the wider end of dispersion for most speakers (imo that's a mistake, I like wide dispersions)

@PoesAcoustics

4 ай бұрын

60 degrees is quite narrow. Keep in mind a 60 degree dispersion refers to a speaker being -10dB at 30 degrees to either side. A wide dispersion speaker would be a 120 degree speaker which is -10dB at 60 degrees to either side. Anyhting narrower than 60 degrees would be extreme.

Thank you for your time 🎉

How does professional RT60 measurements with a dodecahedron loudspeaker compare to measurements with a regular speaker with a waveguide and narrow vertical dispersion? I would assume that with a regular speaker you’ll get much smaller RT60 values - is that correct? What’s your experience on this?

@PoesAcoustics

4 ай бұрын

There were studies done in large rooms that found sizable differences. However studies were also done in small home theater sized rooms and found the oppossite, no meaningful differences. So it seems reasonable to use standard speakers. My recommendation is still to take multiple measurements with different speaker positions to create a composite.

If I ever have the money to build myself a good Living/Media Room (Not a Home Theatre) would you be open for consulting? My ideal room would have a Star ceiling showing all the stars seen from the Northern Hemisphere (Polaris, Beetlegeus, etc.). I think any Media/Living Room would benefit from Acoustic treatments.

@PoesAcoustics

3 ай бұрын

It’s what I do for a living. I consult, engineer, design, commission, and calibrate media rooms, 2-channel, home theaters, studios, etc. I even calibrate multizone audio and outdoor sound systems. If it has the ability to be measured and tweaked, I can work on it.

Matthew, how are you testing for reverb time? Does REW work?

@PoesAcoustics

4 ай бұрын

Yes of course REW works. That is a perfectly acceptable way of measuring it. It's not so much about the tool, nothing inaccurate about REW, its about how you do it. The correct way to measure the rooms RT time will be to place the microphone in a few locations around the listening area and take sweeps from both the left and right speaker (not together at the same time but seperately). This gives you the RT trend int he room over the listening area.

@noahpielert8480

3 ай бұрын

This was the question I was coming into the comments to ask, how to measure RT60 in a multi-channel system. e.g. running a sweep on all channels or one channel (or L+R). Thanks! ​@@PoesAcoustics

What is your opinion about speaker placement especially hight chanel is it necessary to keep all speakers on axis to MLP

@PoesAcoustics

4 ай бұрын

Do you mean is it important that every speaker is aimed at the MLP? Not necessarily. Very wide dispersion speakers often change so little over the listening window that aiming them doesn't gain a lot. I think a lot of people misunderstand why we aim the speakers. It's purely frequency response. If you aim the speakers correctly, you can minimize the HF errors between channels. If the speakers dispersion is wide, there are no meaningful errors. On the other hand, some speakers it matters. My speakers are not aimed, there is some variation channel to channel because of it, but its quite small, a dB or two at the highest frequencies. Aiming doesn't have any impact on things like immersiveness. It's going to be about how consisten the pans sound because of the change in timbre.

@sandeepjohny6480

4 ай бұрын

Thanks for the detailed explanation I have seen you and mr.james doing alot of speaker Measurements Could you please advise which all speakers(make/model) you have observed wide dispersion from your personal experience I am asking only because there are so many brands and different series of speakers available on the market it's very difficult to experience and make decisions but people like you very professional have more experience with various brands it will be very helpful for common people to made decisions

The very small room scenario were surrounds are on 3 feet away from listeners, is it best to elevate 2 feet to decrease the direct sound? How do you treat these very small rooms to compensate acoustically?

@PoesAcoustics

3 ай бұрын

Yes I would elevate the surrounds. I know some engineers that would always elevate like that. Acoustically I would treat the room like any other. Not a lot of absorption would be needed, though certainly some is needed. I would add diffusion too, but of the right type. A lot of diffusers can't be used in small rooms.

Your theater looks great!!!

@PoesAcoustics

4 ай бұрын

Thank you, glad you like it!

After watching way too much content. I just did combo panels all around. My speakers have good directivity so It worked out well.

@PoesAcoustics

4 ай бұрын

If by Combo panels, you mean something like a BAD panel (or the many copies out there), sure. I know some professionals who use those and love them. It's not my preference all around, but it's hard to go wrong with such an approach.

Great video but isn't the whole purpose of atmos is to pin point the actual objects moving. Keep the vids coming. When are u doing a movie demo of ur theater.

@PoesAcoustics

4 ай бұрын

What do you mean by a movie demo? The object shouldn't be tightly pinned to the speaker itself. If you can tell that a panning object is coming from a specific speaker, I would call that a fail. It should be more subtle than that. Think about it, when an object is moving around you, like maybe a chirping bird, without seeing the bird, you can't tell exactly where it is coming from. The pinpoint location is related to visual cues. Hence why you have to look around a bit to find the bird. Movies should be no different. The issue is that in a room the direct to reflected sound tends to be a lot higher and reflections tend to be a lot more coherent than they would be in real life. So adding some diffused reflections helps a small theater approximate a larger real space a bit better. There are other issues too. A really dead rooms increases crosstalk problems, increases comb filtering audibility, etc. Basically, some reflections in a room are a good thing, they help reduce the audbility of natural flaws inherent in a multichannel system.

Thanks for the video. Keep up the good work! I'll keep posting inane comments to feed the algorithm!

@PoesAcoustics

4 ай бұрын

Hey Man, I much appreciate that and appreciate that you understand that. Interaction with videos is so critical.

@Zachary_Setzer

4 ай бұрын

@PoesAcoustics You're on a great run here lately. I've been thinking about adopting Paul McGowan's approach and start doing Q&A style videos where I just answer one question per video in 5-10 minutes and just record a week's worth in one sitting and then post one a day.

Lighting and exposure look great. One thing you might try is the distance your light is from you. Closer will make it larger and softer and make the background darken, allowing for more separation. Farther will light the entire area more evenly but be more flat.

Room treatment is different for home theater and 2 ch. That kills a buttt ton of lame arguments! Thanks

@PoesAcoustics

4 ай бұрын

hah there are a lot of lame arguments.

Great video dude, I’d be interested in a video discussing best practices for BEDROOM acoustics for home cinema, I know a lot of us ( especially in the Uk) are forced to use spaces no bigger than 10’x12’ . Thanks.

@PoesAcoustics

4 ай бұрын

We have a demo room that size coming together so i plan to use it as an exemplar of such spaces.

South African here. Popped up on my home feed. Seems like the KZread algorithm has a sense of humour. IYKYK.

@PoesAcoustics

4 ай бұрын

It's my last name and it's origins have nothing to do with the bad word in South African. It's from a Hebrew word in the bible that was translated in Russia to a different spelling (Poz) and then to Poes in America to make it sound more anglican. The fact that its also a bad word in South African is a bad coincidence.

@dryashnaidoo

4 ай бұрын

Yes and the way you pronounce it is also nothing like the South African word. However, what I found interesting is that KZread put your video up on my home page feed but your type of video is something I never really watch.

@schaunkleynhaus5041

3 ай бұрын

It might be because you have been googling the word allot. Or your phone has been listening to you words and suggesting some content.😂

How about the REALITY of building a FAR HIGHER QUALITY ROOM instead of simply making excuses for suboptimal performance that most make. I have ultra high end rooms constructed for both ultra high end 2ch and ultra high end theater both audio and video. Guesswork is amateur at best so getting it right requires those that understand and know far more than most of the players that claim to be experienced in the business. Another industry that should be regulated.

@PoesAcoustics

4 ай бұрын

Not really sure what you are getting at here?

@davidcross890

4 ай бұрын

@@PoesAcoustics build the room purpose built not starting with what many do which is flimsy uncontrollable basic 2x4 or 2x6 construction

Some of the 2 channel guys have bottomless pockets and no clue about acoustics. You are missing out on a lucrative market if your focus is only on hometheater.

@PoesAcoustics

4 ай бұрын

I can work with 2 channel to. I just don't find they are as open to spending those bottomless pockets on acoustics. They will spend it on cables, tweaks, etc. Not rooms and cables. Which is too bad. I can make a 2 channel room much better. I can actually lower the noise floor many dB. I can improve spaciousness. All sorts of things that get attributed to tweaks, I can do in ways that are many magnitude of degrees greater than those tweaks.

@wa2368

3 ай бұрын

@@PoesAcoustics Maybe, get on audiogon, start responding on some clueless threads and explain what you can do.