Poes Acoustics is a custom home acoustics design consultant with over 20 years of experience in the industry. Matthew Poes is a well-respected acoustical engineer with a very science-based approach. Poes Acoustics has led the design of home theaters, listening rooms, and even mastering rooms that have ranged in price from $5000 to over $1 million. Few companies have the necessary design expertise to be able to design and manage the installation of such high caliber home theaters. We specialize in sound mitigation, acoustics, and home theater design. In addition to decades of experience with acoustics, sound mitigation, and system calibration and design, Poes also works as a senior technical editor for Audioholics. Through his work in the industry, work in the press, and strong reputation, Poes has deep connections to designers, manufactures, and integrators throughout the country.
This is a big deal. Amazing that what now, after you mention it, seems obvious, isn't talked about everywhere. Thanks for presenting this. Nearly everyone here in Florida has a concrete slab under them. What you are talking about needs to be on everyones checklist to address at least to some degree. Why bother with big subs at all if the inertia of the seats and house isn't considered? Thanks again. I'm going to talk about this to some folks--they'll think I'm a genius!
I'm running a 2.2 home theater in a small space using a MiniDSP HD 2x4. Being able to tweak speaker in-room response while also optimizing my subs with MSO has resulted in a theater experience that is really solid in spite of not being a surround system.
Hi Matt, I need your advice on what subwoofer to get for my room size. I’ve been using an entry level sub of a reputable brand but nevertheless an entry sub. Last year I upgraded my speakers, they are referenced capable, and very soon it became obvious that my sub just couldn’t keep up with these speakers. I’m looking for an “endgame” sub(s). I live in Costa Rica and the shipping from the States is pretty expensive, so I’m marrying with whatever sub(s) I finally choose. My room is a dedicated sealed HT room of 8.6 ft x 10.56 ft x 17.81 ft (including the space behind the AT screen). I have two rows of seatings but don’t have enough space to place subs at the back, just fyi. I was considering sealed subs from PSA, 18 inch (S1813M) or 21 inch (S2112M). I want reference capable subs, but considering my room’s size are 21s overkill? Is 18 enough? How many do I need? Hope you can help me out here.
Thanks for for your informative videos Matthew, I'm doing my best to get edumacated, at complicating the uncomplicated. I recently purchased a "Dayton Audio Imm-6 mic" and the "Audiotool App", & the "Dayton Audio DSP-LF Low Frequency DSP Controller" it uses the free"iWoofer App" on Android & iphone, or the $5. "iWoofer Pro App" that uses a wizard to measure and set up the subs with automatic room correction. Unfortunately, the Pro version only works on iphones & I don't have freakin iphone. So I'm using the imm6/Audiotool on one Android device while using the free iwoofer app, on another device, it's a bit tricky, but it's definitely made some improvements, less boomy and I've tightened up the bass, however I'm still trying to get my head around it, unfortunately the crossover doesn't extend below 20Hz. I did come across some interesting articles on an appropriately named site, that I can relate to, called "The Cult of the Infinitely Baffled"
I went PC > DL+BC > DAC for my 2.2 setup. Made a huge difference for listening anywhere on my big couch, plus Dirac is waaay easier and FAR less time consuming than manually dialing it in. Get the multichannel version to add more speakers/subs if/when you get bored. it goes on sale 30% off a couple times a year too.
Thanks Matt, very interesting comments. In my case I have both a 2 Ch and surround in the same room - separate mains but common subs (4). I do want to optimize subs for 2 listening positions for 2 ch, so this works out.
Literally just did this due to our receiver being in for repair. Running stereo speakers and dual subs out of a MiniDSP 2x4HD, to try and ensure the best bass and tonality for our entire couch while we can't take advantage of Dirac. Running optical out of the TV to the MiniDSP, so it's a neat stereo option for people who don't want to run a full surround setup
MiniDSP Flex in terms of DSP/DAC is all one needs if he is serious about 2ch audio. Is it necessary NO does it give BEST result in an not so ideal room YES. And for majority 2ch setups go into not so ideal or not so well treated rooms. So going for MiniDSP makes absolute sense. It really helps optimize the listening experience for that one main area. Even if no SUB on the system and only a simple 2ch setup with capable floor standing speakers. MiniDSP or any other processor can help optimize those speakers to get you best in-room setup without needing to have to spend a fortune to get room treated and optimized. Edit: I made this statement in general to backup on why one would need MiniDSP and is getting MiniDSP or any DSP worth it for a 2ch setups instead of simply getting an audiophile DAC and be done with. There are lot many benefits.
In South Africa a Poes is the most commonly used swear word - and means c_nt!!! So I keep on recommending your channel to local South Africans, with funny results 🤣
Is the air gap layer better when its closest to the audio source side of the wall or furthest layer out? Or in the middle. Not sure if theres been good tests to prove one way vs another
Doors from another "Professional's" perspective - Start at 2:56 and then laughable at 3:14 (end at 3:20) - search on "Sound Isolating A Home Theater Room: AH Smarthome" to find the video post Oct 29 2020. How is the average consumer supposed to be able to deal with such misinformation 😢. A "Professional" many may be, however reputable is another question altogether!
Useful info 😎, I find this interesting as I’m still planning a new build. I always mean to ask.. when you say your daughter’s bedroom and wife’s office are the other side of your theatre and you can listen at reference without really disturbing them. How is it stopping the long low frequencies? Don’t they say a 20Hz wave can pass through 1 metre of solid concrete like a knife through butter?
On top of that, the rigidity of the wall assembly due to the extra layers has it's own trade offs of raising and lowering resonant points. The trade offs never end!
Thanks for the awesome videos. Just a follow up question. In your calibration what do opt for when not using trinnovs or AVR’s with multi sub out? Do you suggest time aligning😂 the subs using a MiniDSP measuring from the MLP. Then feeding this to the avr for multi measurements, EQ and calibration. Or do you instead think it’s better to time align and EQ on the MiniDSP and then feed a flat sub signal to the room correction software?
Just fyi, 2500mm is ~8ft. That's gotta be a contender for biggest home theatre speaker ever! j/k, mental math is tricky on camera. 4inches to 10cm or 1' to 30cm might be an easier way to convert for you than 2.54cm / 25.4mm to an inch. If you ever need imperial to metric conversion, just ask a Canadian.
Any chance you can make a walk through video for us less educated people. Why your speakers are placed where they are, your setup for the room, maybe showing where your processors/amps are located and setup. Just a overview of how your room is setup, why you made the decisions you did and would you do them again if building everything again. Im very much an amateur trying to learn more and more as i can but very much not technical in the audio space at least. Maybe a short demo of a movie actually playing in your room
So i have a 5.1.2 atmos system. Am using Kef Q750 towers and have ELAC Debut 2.0 A4.2 atmos speakers on top of the towers. Have 8' ceilings, and i dont hear anything coming down, but they do seem to open up the sound stage. I never thought it was a good idea to place the atmos speaker anywhere, but the ceiling, but i cant do ceiling speakers at this time. So this is what i got. Do you think adding the back Atmos speakers would make much of a difference? Then i could go from a 5.1.2 to a 5.1.4 fairly easily.....
What do u think about the Monoprice M-215? it’s on sale right now and I’m really tempted to get it. I didn’t know if you had a better suggestion for about the same price. Love your content keep it up.
Thank you Matt for another great educational video and for trying to educate us, the home theater enthusiasts on sub + speaker time alignment. I always try to optimize for the MLP and I try to get it so there little seat to seat variation in the right and left seats. It's always a challenge especially in an open living room concept. I use REW to Time Align and EQ my 4 subs and do 3 measurements at different positions for each sub and average the measurements of each sub. This method doesn't yield better results in seat to seat variation as compared to a single mic position measurement for each sub. My next step is to learn MSO and try that in my room.
I spent quite a bit of time manually optimizing my subs using EQ and delays. While the overall response improved, I was never completely happy with it as there were some nulls that I couldn't completely eliminate. I eventually decided to try MSO and I'm amazed with what it did. The troublesome nulls were eliminated and my seat to seat variation was significantly improved. Although MSO requires a non-trivial amount of effort to learn and understand, for me it was totally worth it.
Wouldn't the standing waves be the biggest issue as you move from seat to seat more so than the small time alignment shift? I'd think having the delays set incorrectly in your receiver and the delay caused by the sub amp/dsp would make a way bigger difference than the time shift caused by seat location.
Something something room modes, xover, and time alignment. Rew, mic and mini dsp should be transformative. New subs will help for sure, if you calibrate them.
When I had my couch against the wall of my 14'x14'x8' room I had darn little quality bass. When leaned 2 feet ahead - boom - lots of bass, sit back little bass. Room modes and a standing waves are hard demons to beat. The person posing the question may also try adjusting the phase and/or polarity on the sub to match to speakers. Placement is also pain. There's just so effort needed to integrate a sub into a room/system. But, done right - Five Stars! After that it's up to the artist/engineer to provide the quality bass in the recording.
Woohoo! Specs 250 watts RMS on the amp, I think the big problem is a hard cross over at 25hz and lower. It should be fine in most cases, cross over could also be an issue set wrong as it is adjustable. The Sub is likely over 20 years old...but that's not always a sign there is a problem.
Hey Matt, picked up a SVS ported 12" sealed Pro 2000 subwoofer. It's excellent, all my speakers are Kef besides the subwoofer, do you recommend staying in the same family for Subwoofers? Also, the speakers I have are the Kef Q750 and they can go as low as 48hz. They always recommend that you crossover at 80hz, even my receiver recommends 80hz as the CO point. My question, is it better to switch the crossover at 50hz, as to get more out of the Q750 speakers? It's funny, when I just ran my system with the 2 towers only for movies, they sounded amazing. Have a 5.1.2 system now.
I have a SVS PB1000 Pro. I you haven't yet try changing the polarity setting within the cell phone app while connected to the sub. That was only one thing I had to do to blend my sub into my system. Distance setting in the AVR is another challenge. Keep in mind the latency in the SVS amp is about 5ms(5 feet). So, you may need to add 5 feet+ to your distance. Have fun, it's worth the effort to get right.
You would need REW measurements to find the best crossover and the best distance. Choosing the best XO without any room measurements is basically impossible. Phase and wavelets come into the equation and you can't achieve a good xo or sub distance without REW. I had to switch to LFE+Main and inverse sub polarity to get the best results...but almost everyone will tell you LFE+Main or double bass is wrong. Even me, until I tried this setting 😅
@@welderfixer to be honest, I don’t know what all the settings in the app do. Is there a place that explains what the polarity settings and others do? Thanks for the help, really appreciate it.
@@michael-4k4000 The app does have some instructions in the app but are hard to read and are limited. I can tell you that on my Android phone switching the polarity the Orange high lighted side is the one in use. Also, be sure that your BlueTooth is turned in your phone first. The green symbol at the top of the app tells you are connected to the sub. I had a heck of a time with that early on. There may be a video or two on RU-vid by now that explains how to use the app. I wish I could produce a video about but I'm not good at it. Post again here and I will try to help further. Other great folks here will also offer help. Take care.
I actually experienced this. I first had the top rear too low (but still within the specified angles). What happened was that I heard the top rears as just rears. Once I placed them higher up I got better separation and all of the sudden the atmos effect was there! I was pretty amazed since I only moved them a foot or so higher up on the back wall. I think whats happening is that the brain cant hear the sounds as from two separate places. (Im sitting closer to the back wall so the top rears actually end up on the back wall.)
