Thanks youtube algorithm, this was the perfect recommendation, was looking into changing my door, but I wouldn't have thought of communicating doors. I see much more inconsistent bass response on the right side of my theater, which is where the door is. The current door is basically cardboard, so besides not waking my kids in the night, is it a reasonable assumption that I can get smoother bass response when I replace it?

Hey Matthew great video. I got a solid core wood door and have weather strips installed in the jamb. I noticed the door rattles when i tested my speakers. The top left corner of the door when i push on it moves. Noticed the door is not latched fully. When I took out the weather strips it latches properly. I want the weatherstrips in, can you recommend a better heavy duty door handle with a longer spindle that will latch a lot better? Currently using weiser door handle system I got from Home Depot. I have the spindle at extended position and it still is not latched the best.

Really good topic and I ended up with a similar conclusion, we call it an airlock but the same thing.It will be interesting to follow your room build.

@PoesAcoustics

3 жыл бұрын

I am glad it's useful. Thank you for watching

Hey Matt. Would adding a layer of AcoustiBlok on each side of a mineral core door help? Then overlaying acoustical panels. 2: how about staggering the interior wall leave a gap and a standard 2x4 exterior wall with a dual door config? Thank you

@PoesAcoustics

Жыл бұрын

Anything to helps. It’s more about how much. Let’s say the door is 36”x84” and weighs 100lbs. It likely has an STC rating of 32. Adding two layers of MLV would only add 36 lbs of mass for the 1lb stuff. That would increase the door to 136lbs. You get 6 points for each doubling in mass. So the door is probably around STC 34. Use the 2lb stuff and the number goes up to maybe STC 36 or so. That is a noticeable improvement but it’s not a huge increase. Communicating door assemblies are always going to be hugely better. You can easily get between STC 45 and STC 55 depending on airgap, door mass, etc. Offsets between doors are better mostly at addressing some Hf noise that sometimes bypasses doors through gaps or holes. It doesn’t change the STC much if at all. It’s worth it if it can be done conveniently. Small offsets in a narrow corridor won’t help and will be a hazard. I have an STC 47 door in my current theater. It’s the best you can typically get from an all wood door assembly. My last theater had communicating doors, 1.75” thick each that weighed around 120lbs and 150lbs each (different cores). There was a 10” to 12” gap between the doors. That wall measured a good bit better than my new wall and subjectively blocked more sound. So I can say that in my own experience the dual door assembly build the way I built that one outperformed even a good STC rated single door.

"Sounds" like a lot of good information. 2 questions.... Communicating doors--how are they "joined toegther? By a shared frame? Or are the 2 doors "decoupled"? I've seen "communicating doors" used for high-end home theater installs. There is a gap between the HT wall and the wall on the other side for the other room. the 2 walls dont touch. But there is this space ... ISO-Doors...at 340/450 pounds won't that be too heavy for most people to open/close??? :) You'd need to be a Powerlifter/bodybuilder.... How could it be sueful in the home??

Very informative. I really appreciate this type of video. Finding information on doors and who to trust has been a bit difficult.

@PoesAcoustics

9 ай бұрын

Glad it was helpful!

Nice video, well explained while showing numbers of different configurations. How much difference would having a small lobby make with about 4' between 2 doors?

@PoesAcoustics

3 ай бұрын

Massive difference. A lobby or buffer space massively improves the LF isolation. There is also loss over distance now. On top of that, you could add some absorption in the lobby area and gain even more. It’s a sort of communicating assembly of such great distance they no longer communicate. You get much of the benefits of communicating assembles and more. In my house the staircase landing is at my theater and office entrance. That is all that is on our second floor. Then the bottom of the stairs goes into the kitchen. With a door. The distance is around 20 feet. When I have movies going at reference levels, you can absolutely hear them on the other side of my STC 47 door. Go down stairs and it’s faintly audible. Go to the kitchen and it’s still a little bit audible. Not a lot, but at night it can be heard. Shut the thin wood and glass door, and nothing is audible. It’s that big buffer space that gives all that benefit.

@rojolo4141

3 ай бұрын

@@PoesAcoustics Thank you, I had read that it would make some difference but wasn't aware it would be described as massive. It's now definitely in my plans.

I thought this was TMI, but he was pretty thorough and pretty interesting

These types of videos are great and exactly the information that I am looking for. I hope to build a home theater one day and I am all about gathering knowledge outside of thousands of pages in forums and reading. Keep up the great videos. You mentioned HVAC leakage in another video and comment on this video. Do you plan to cover that topic in a video? Thanks again and keep up the great content!

@PoesAcoustics

3 жыл бұрын

Hah I just commented on that for someone else a second ago. Yes I will cover it. I want to wait until I’ve had a chance to talk with the HVAC guy and have some more firm plans. One of the biggest challenges is always budget. I need to find out what kind of HVAC unit we will use upstairs and what options I have. Then I can plan for how to soundproof it. Part of how fix fan noise problems is by avoiding making fan noise. Meaning you optimize the fan in the unit. I need to find out which units we can use, how large is necessary, and then find out if certain versions have better fans with more noise optimization. My builder has an HVAC guy he likes to use and I need to know what brands he installs to figure this out.

@TheArthilles

3 жыл бұрын

@@PoesAcoustics Awesome! I'm not aware of many options. I've seen some people do baffle boxes. I don't know how much they help to not suffocate you while also soundproofing from fan noise and keeping your wife happy. I look forward to hearing your opinion after talking with your contractors.

@PoesAcoustics

3 жыл бұрын

@@TheArthilles I honestly have pretty strong opinions on this. I’ll try to be sure I cover it all when I do my video. With HVAC noise control, you have four main issues to address. You have airborne sound, breakout sound, air noise, and structural born sound. Airborne sound is all most people consider and that is sound traveling down and through the duct. It’s similar to those science museum communication pipes. If the ducts are hard steel, sound will readily radiate through the ducts from room to room. It’s a serious problem because there is often very little attenuation. Breakout noise is that same airborne sound but radiating through the duct walls. Steel duct has a strong resonance but otherwise has about an STC of 25-30. By comparison, flex duct is between 5 and 15 depending on the type. Acoustical flex duct is very good at absorbing sound that travels down its path. Part of why is most of the sound simply escapes. Air noise is the whooshing sound caused by turbulence. It’s the sound of air you hear from a vacuum or port noise on a subwoofer. It’s largely dictated by the velocity of air and the aerodynamics of the ducting. Finally you have structural born noise. That is basically fan noise or flame noise or other mechanical noises that transmit through the rigid duct. Flexible ducts don’t have this problem, nor does duct board. But steel duct does. Airborne noise is removed with sufficient silencers. Some means of absorbing sound as it travels down the path. It’s easier said than done. It takes 10 to 20 feet of silencer to be really effective. There are some very good 6’ ones but they are very expensive. Breakout noise is fixed with steel ducting that is dual layer, insulated, well damped. Lagging and insulation can be added too but it can also make things worse. It’s all long to explain and this particular problem is very expensive to fix. Mechanical noises are best fixed by decoupling the ducts. Flex duct works well for this potentially. A special flexible coupler for the main trunk of the supply and return. Decoupling the unit itself. Things like that. Stiff ducting is better for airflow and airflow noise. But it needs more damping and decoupling. Air noise is the hardest. Making the ducts larger lowers the velocity and air noise. But there is a lot of other tricks to consider that often are harder to implement. I will do my best to cover this. I wish I had all the types of ducts to really be able to show people. I know these issues and how to fix them. But I don’t keep HVAC materials sitting around. At the end of the day, making an hvac system really quiet is really expensive.

@TheArthilles

3 жыл бұрын

@@PoesAcousticsI've heard about some of the things you described but never put them together to know about the different options and how affective they are. Here is one of the examples that I've seen. kzread.info/dash/bejne/kZWDsLuqj5vcnrQ.html I'm glad I found your channel. I've enjoyed hearing your talks on Audioholics and I look forward to hearing more!

This is easily the best video on the internet! I'm just about to build my own home cinema on a new build so this video couldn't have came at a better time. Did you find any information on how many STC points can be gained when decoupling the door frams when installing communicating doors?

@PoesAcoustics

3 жыл бұрын

I did something like that when doing my last theater. The doors were not decoupled from the frame. I actually filled the gaps with a highly damped cement like product. However the two doors were attached only to their respective walls. I then built a special frame material that acted as the door jamb and decoupled both sides to some extent. A 1x10 piece of poplar was split at an angle at 5” and re-attached together with a kind of casting urethane. I later discussed this with Ron at NWAA who seemed to suggest it was a heroic effort with little benefit. That I likely didn’t need to bother. What I had already done was good enough. Including that the doors themselves weren’t all that good to begin with. You really can’t DIY a good high STC door unfortunately. You could buy a rated STC core material and build a door around it, but you may spend most of the cost of a built door. Now if you have a good door and you just want to take it the extra mile. Like if you buy a pair of these Isostore doors, I would suggest that cementing the frame in place could be beneificial. It would likely only gain a point or two but it’s cheap and easy. They don’t suggest it’s needed, but also pointed out that it is needed to get past STC 60 in the assembly. So I wouldn’t be shocked if you could actually gain a few points, assuming the door and wall are not weak links and you don’t have other severe flanking sources. I should do a video on flanking. This is really related to that.

@jamesbell3708

3 жыл бұрын

@@PoesAcoustics @Matthew Poes Thanks for the excellent reply, this has helped me make my mind up on what to do. Purpose built door is the route I'll be taking, the cost of a door doors doesn't seem high now compared to the performance. I look forward to your future videos!

do you think if you can't soundproof a door then soundproofing the walls is a waste?

@PoesAcoustics

2 жыл бұрын

Mostly yes. Without a soundproof door the door opening is a huge sound leak. Of course you can always upgrade to a better door on the future. Very hard to soundproof a wall without ripping it apart. But in general the walls should not be more than 10 points apart from the door. A typical hollow core door is only 15-20 STC point. Solid cores are maybe 20-25 at best. Many are rated higher but don’t test as well in practice. So that means a wall should never be more than STC 35 and that’s what a normal wall with insulation is.

@Azzy_Mazzy

2 жыл бұрын

@@PoesAcoustics what about changing the door location? lets say an outdoor shed turned to hometheater with the left wall close to critical areas, it seems like putting the door on the right wall is a worthwhile measure to lessen the noise or maybe just build a another shed connected the door so you go through two doors and "large" air space

@PoesAcoustics

2 жыл бұрын

@@Azzy_Mazzy that is too specific for me to respond to. I would need to see the situation and better understand the materials involved. Most sheds are made of lighter weight materials than a soundproof space so that changes everything.

@Azzy_Mazzy

2 жыл бұрын

@@PoesAcoustics the shed is not built is just what i want to do get the noise far from the house

@PoesAcoustics

2 жыл бұрын

@@Azzy_Mazzy it may not be a bad idea. I knew a guy that build a recording studio that way. The main problem you would have is that the shed is not built to typical residential building standards. As long as it’s built properly to handle the wiring and AC(if needed) and you are careful with how you do the soundproofing, it should be ok. While it’s impossible to totally soundproof a space, you can dramatically mitigate it. STC 55 or higher is very achievable at a moderate cost if handled during construction.

5 mins in and i'm thinking the only true solution is have a hidden door/hidden wall entrance into your theatre... Batman Style :P

@PoesAcoustics

3 жыл бұрын

Yup that would work. An offset entrance like that with two doors between the theater and house is always the best. In high end home theaters, it is common to have a little entrance area with concession stands and/or movie memorabilia. This is why. Even in my last theater, while I didn’t have this, the ability to close the door to the basement was enough to render any sound leaking out my doors as a moot issue. The largest source of noise from my theater to any other part of the house was either through the floor/ceiling or the HVAC.

@TysonHook-22-

3 жыл бұрын

@@PoesAcoustics ​ @Matthew Poes Yeah I was mainly just playing around but its for sure a real world solution for those able to accomplish such a expansive and expensive project, for sure excited to follow along with both you and Genes new home endeavors. I cant wait till you get into the HVAC side of things... Im guessing youll avoid having any HVAC running through your new media entertainment room? A noisy ceiling HVAC has for sure been a huge problem for me for the entire time ive live in the apt I rent. Just last week I decided to create a DIY block maze in my HVAC tubing, my tubing is square metal tubing about a foot wide. I decided to take some 2x4 scrapes that fit inside the tubing in various ways, cut and glued some useless acoustic foam to the wood pieces, since I just had some old 12"x12"x1" cheap foam boxed up in a closet so figure in this case it actually might help a bit to scatter and diffuse the air turbulence further then the blocks alone... I then tossed some magnetic strips on the bottom of the wood pieces and stuck them inside the metal HVAC tube in a maze like pattern surrounding the noisy vent exhaust in my media room. Its by no means perfect but I instantly noticed a dampen difference that was measurable using an SPL meter on my phone, not the most precise measurements but it dropped from a room ambience in my MLP from a bouncing 50-65dB down to a much more comfortable 30-40dB, my HVAC has honestly never sounded quieter to my ears in the 3 years ive lived here, my HVAC isnt nearly as deafening to my right ear anymore which is only about 5-6 ft from the vent exhaust area... I literally began to notice the sound stage of my front speakers come to life just because I was better able to hear the sound coming from my right ch, KEF LS50, the vent noise was no longer drowning out the sound waves as much. I also stuck some foam pieces on some of my vent cover louvers temporary but I'm planning to install new vent covers in the next couple weeks that will hopefully further help diffuse the sound and im gonna do a more proper fitted maze in the tubing... like I said I just used scrapes so there not all fitted fully across and not in the greatest maze pattern that I could do, so im gonna take things a little further since my test experimentation has worked out so well for me and cut some proper fitting pieces and likely go with larger 1x6 pieces instead but unfortunately that's about as far as I can take things in my rental but its sure better then nothing at all!! The HVAC noise use to be vary fatiguing to my ears and I honestly didnt even realize just how much so (you kinda just adapt and get use to the loud ambience noise) until I dampened things down and it was a instant sigh of relief from my right ear for lack of a better term.

@PoesAcoustics

3 жыл бұрын

@@TysonHook-22- I knew you were joking but it was a serious solution. You raised a good point. I will have HVAC. You need air turnover in a theater. While a potential solution is the dead vent approach, I won’t do that. Instead I will have a separate smaller unit dedicated to the office and theater. I will then use acoustic ducting and duct mufflers in the theater runs. I will decouple the hvac when it is mounts to avoid vibrations. I will also overdose the ducts to reduce air velocity and this air noise. Still need to work with my HVAC guy to get this planned.

Harsh reality