We actually do have some of the smartest viewers in the industry btw. Our message inboxes are full of amazing insights and thoughts people have after watching our videos, and it gives us many ideas for future content. Just the way youtube works though, we've found that unfortunately the slightly clickbait titles perform a bit better. You should write a complaint to youtube about it.
I’m from an era when it wasn’t as easy as watching a video or perusing the internet for info, what you showed was knowledge that I learned from quite a few years of reading and research. Quite informative and loved every minute of it.
i used the local library in 1989, Sony SQ Quad, all i needed was a sub and centre speaker then. Oscilloscope did the rest. Kept the speakers, only updated the DAC. Math then is the same, you only got better codecs now.
imagine that, im not even a sound engineer and i have all this random knowledge about sound engineering because i watch random youtube videos in my free time
I purchased my first speaker building book from radio shack in 1983. Later the loudspeaker cookbook. Then speaker builder magazine. Learning how the various woofer loading in cabinets mimic electronic filters were invaluable lessons in understanding the marriage of electronics, acoustics and physics of loudspeaker building.
Was gonna say the same thing. Even at local libraries, finding pro audio & studio engineering books wasn’t easy unless I found a way into Portland (25 miles to Portland is a long way for a kid). When I did finally go, that was where I discovered the old (RIP) Powell’s Technical Bookstore which was separate from their main store and only had tech books. But even then, we didn’t have these great videos.
All clearly explained for us who aren't sound engineers, just an average hi-fi enthusiast here learning something new. It's impressive just how directional that big bass cabinet is, and the science around making it work is fascinating, same for the 2 cans being moved closer and further apart. Thumbs up!
I have been into home theater for 20 years and have built various vented subs, but I never knew about the pressure waves from the port changing direction with relation to the driver. Thank you for sharing this knowledge and taking the time to present it in such a straightforward, yet entertaining way.
everything has its profession to get the best out of it. i like to describe speaker as a racing car. no matter what speaker brand you have, you never get it to perfect for the most part. just like how you put your bass in certain of the room, you get the harmonic effect and one side of the room sound louder than the other side. could be the desk, the chair or computer that distort the sound of the bass. you centered the home theater speaker perfectly where you sit, but the person who sit 4 seat down from you wont theat the perfect 5.1 or 7.1 surround sound experience. just like racing car, each car is tune for specific track once you take it to another track, its not optimized unless you tune for it again
@@BlueRice It just can't be only me who demands more than one Subwoofer? I like four of them and under the bed should it be enough room for a couple who work together as you watch movies laying down... Just be careful they do not redusece eithother...
At around the 6:06 mark that "jet engine" shape is called a "venturi". Like a naturally aspirated carburator. Helps low pressure rush to high pressure uniformly.
I've designed a lot of speakers, including some with pretty esoteric radiation patterns. This is an incredible demo of large room /outdoor bass management, and the explanation of the vent resonance was incredible. Really impressive.
Now I understand what John Atkinson (Stereophile) means when he speaks of the driver at minimum motion at the tuning frequency of the enclosure. I could never envision this in my brain, but your demonstration makes it very apparent.
In my opinion you are the only guy who has uploaded a video for these rare speakers. You and I are the unique people who purchased them. Anyway I am an engineer from India, bought this fantastic set of 2.1 with a passive diaphragm sub woofer. Nearly 20 years ago. I have a similar problem. That thick cable with multiple wires originating from the small satellite speaker and going towards to the sub also develops a loose connection in the connector and starts making weird sounds intermittently, this section too needs to be looked into. Your video is lucid and helpful thanks for your effort, greetings and best wishes from India
Thank you thank you thank you for playing the sound from the speakers. So many people drone on and talk about speakers, without demonstrating!! You rock!! 😆
this is important work. thank you for demonstrating. Its not about how much you understand the graphs and or how to specifically tune them perfectly. But at least opening the public up to how muchhhhhhh the acoustics, phase and placement matter for sound.
I feel like this dude walked to the street and found the first guy and offered him $20 to stand there for 10 minutes. Then I started to watch another video and same with that one. 😂
You did an amazing job teaching a topic so many take for granted! As a rookie going into bass systems and building this really opened my eyes to how bass works, I've watched so much videos about bass but this video? It really takes the cake! Almost feels so illegal to watch a video this good! This is very helpful in understanding how bass works! A very sacred sound! Great video!
I love the raw technical nature of this video. Spent Two years on the road where I was experimenting with subwoofer spacing at half wave to generate / reduce system resonant frequencies to adapt to different locations accoustics. Got a nice spreadsheet out of it that has been very useful over the years
The engineering behind cabinets is just mind blowing. How much would you say that tuning your system every show isn't as much about acoustics vs compensating for the air? Now that I'm watching this multiple times, it makes me think next time I touch a FoH board. I understand acoustics play a major role, but you can tune it ear perfect, but still sound dookie. Bass vibration is weird. High vibrations are weird. Y'all onto something! I need more!
this man so far has been the most knowledgeable and intellectual professor of sound design and engineering ive ever seen over RUclips. i will learn from you everything there is from you.
I really liked how straight cut and well articulated Devin delivered this video. I usually dont click on or expect to learn anything from "things you dont know about X" videos but this one was very good
Directional sub is so much fun! I done this with a subs suspended up in a dome (together with soundscape speakers all around it at ear level). They were placed at just the right distance and with the right delay to send the frequencies used in the soundscape directly downwards in a cardioid pattern. Those kind of projects are the ones you remember the most (in stead of the normal FOH-installs).
Great video and informative!, the helmholz resonator, or bass reflex uses the concept that the air in the enclosure is physically time delayed in order to exit the port at the same time as the woofer cone is moving forward and as a result, the bass output is doubled, however, the box and port need to be tuned to the resonate frequency of the woofer/subwoofer
After years of building boxes from sealed, to vented, to bass-horn loaded, and simulating those boxes in HornResp, WinISD SpeakerSim, etc, there was nothing in this video that I "didn't realize" but I do really appreciate the cool slow motion and physical representations (the spring/stick/box) done in this video. It's a fantastic way to demonstrate what is happening to the layperson or beginner in DIY audio.
This was definitely an interesting video. The spring stick box thing was physical representation of something that I saw in a paper from Mazda. Using resonant frequencies in an automotive intake to get more air into the cylinders. Changing the length of an intake to have power over a wider rpm range instead of a single peak rpm. It works. I think the Porsche 959 was the first to use something like that. In the diagram it showed using the air as a spring. A mass with a spring on both sides, the mass also being air, the spring is air inside a runner. The mind blowing part is when an engine valve snaps shut, the air stops and builds up on the back of the valve, then springs back into the intake which can help another cylinder with an open valve take advantage of a micro charge. Every little bit counts.
@@pgtmr2713 correction: First patent for variable geometry intake manifold was by Daimler-Benz I believe, in the late 50s. Toyota had their T-VIS which came in 82. My old 88 Mazda RX7 also had 3 butterflies, two smaller and one larger. Not all of these use pressurisation from resonance, like my turbocharged RX7, which wouldn't care, pressure increase due to resonance would probably be negligible as the turbo gave 0.8 bar.
@@JakkeJakobsen Yeah but the T-VIS was dual runner. More about keeping up the velocity. Same as the Taurus SHO. Not sure about the old Benz, but I was thinking more along the lines of something mass produced. Good on Mercedes if they got there first. Never really got into the RX-7 beyond "rotary," but good to see they were using all they could. I had an 88 MR2 4AGE with T-VIS, and have a Mazda KLZE V6 with VRIS. Collected all the intakes for the KL out of curiousity. Similar layout to each, but the only thing they share are the vacuum actuators. At low RPM all runners pull air from the throttle, mid rpm a valve opens and a cross tube opens up so the 2 banks can share some air, High rpm a second tube opens, so all runners can pull from the throttle and 2 other shared crosstubes located close to all runners effectively shortening the path. T-VIS had a 8 runners to 4 cylinders one runner shut down at low rpm increasing the velocity in the one runner for each. Badass 1.6 liter engine. :-D
same for me. This kind of knowledge sharing has and deserve its place on yt.. //My sub specialization in EE studies was electroacoustics at university and been building boxes since my childhood.
Good thing its not about trying to hear the bass through a youtube video, its about how it works and its relationship with air and friction. The point is about 3 feet over your head
Excellent tutorial! All the information is explained and demonstrated in logical order, using clear language. Any needed jargon is explained clearly at first use. This is how all training and educational materials should be structured.
This was actually a very cool and informative video. I started working with PA systems in the early 80s and was positive I knew all I needed to know about subs. I learned something here today about subs I didn't know prior. Thank you.
Wow, that was super interesting. One comment I have is that it wasn't always clear what the graphs were showing, and I had to pick it up from context. Once I figured out what the graphs were showing for each section it was great, but between sections the graph was changed (as is appropriate) without the presenter always explaining what they were. For example, sometimes they were relative response, sometimes they were relative phase, sometimes one of each. It would help a lot if there was some label or maybe an intro screen for each part of the video detailing the test setup. For additional context, I am the sound guy for my local church and I picked it up as a hobby from the old dude who _did_ go to school for sound engineering. I am a software developer by trade, and I know about fourier transforms, harmonics, etc. So I am not totally in the dark about the science, but this was a really interesting lesson. Thanks!
Great video. I love the explanation of null points in sound. One thing that doesn't get mentioned is that a driver is cone-shaped. So the portion of the driver at its rim, will have a very limited range of motion in contrast to the portion of the speaker closer to the voice coil, which will have the MOST movement. So when looking at air pressure and how that air will move, it's good to understand that air at the sides of the driver will move slower than the air towards the center. So creating a vent that tapers from the source, is essentially mimicking the way the air will flow from the driver.
This is REALLY interesting! Can I make a request? Ditch the background music. I found it got in the way of the content. And I really enjoyed the content! Thank you.
A complicated subject, well-explained without using math and without leaving out important parts. I'll be referring people to this video. One request: Please don't add background music. It's distracting.
Great presentation! At 9:03, you are outlining a hyper-cardioid pattern. This is exactly the way a dual diaphragm mic, like a U87, achieves variable patterns. Amazing to cover that much info about reflex speakers without mentioning Theile-Small parameters. Each box is designed to work with those specific driver physics. Please don’t expect that performance when you replace a driver with whatever is on the shelf locally.
6:20 the constriction increases velocity as well (yes like a jet would) It could also promote the flow of sound in one direction and not the other. Jaguar's old V12 engines had a trumpet design for the air intake which would allow excellent airflow (for the small diameter at the point on constriction) compared to a normal restriction. The shape accelerated incoming air which reduced the backflow of engine noise via the intake (induction/intake noise).. Thus you had a quiet luxury behavior uncommon for a big performance engine. What design is behind that constriction in the subwoofer would be very important as well.
We will have to ask the Nexo team if it’s the Venturi effect which results in the difference in SPL. Even if the Venturi effect is taking place, our intuition suggests that the main reason the SPL increases is because the shape forces the air along the outsides to flow as quickly as the air in the middle through the port length. This reduces the possibility of multiple “layers” of air moving at different speeds which can cause turbulence. Perhaps the Venturi effect, if it is happening here, also somehow contributes to this laminar airflow effect. Maybe this is a good excuse to make another investigative video!
Up until this moment, I used to be very proud of the Bose system in my car, the Onkyo home theatre I have at home, the mighty Sony Shake 6 system I take to parties, hell even that wooden box I call " subwoofer" at the back of my other car... .... I was happy & blessed with ignorance.... and… and you just blow it all off, piece by piece, information by information, test by bloody test……...Never felt so naked, so vulnerable and so homeless after a YT video like I feel now………I think I need a hug😞
The explanation is that simple..... Just because the person REALLY understands the subject. This is what I like the most - complex things become clear.
The one about the airflow that flows more smoothly through the narrow passage reminds me quite heavily of the venturi effect that's present on the floor/underbody of the 2022 Formula 1 cars, I assume this follows the same principle?
That’s a very interesting observation, would have to ask the engineers at NEXO. It seems that there would be less pressure during the construction, and whether this is what results in less air turbulence is something they would have to speak for. Our understanding so far has been that the constriction results in a more laminar airflow, where the air along the edges is forced to continue to travel through the port as quickly as the air in the middle, reducing the possibility of incongruent speeds between layers of flowing air, which causes turbulence especially near the edges in a straight port at high air velocity.
I've always wondered how the bass coming out of the vent or port worked. I'm not into pro audio as I am home audio enthusiast. This video actually shows how the air changes direction as the frequency changes and also shows what happens at the subwoofer's resonant frequency. It's really cool to finally know after all these years how it all works!
I love music, I love bass, and I would love to design and make sound systems. I just don’t know how. However this video showed me that it’s a beautiful industry with brilliant engineering knowledge. Now I’m starting to feel like this is what I want to do in my whole life, I want to learn to design these beautiful masterpieces. Thank you for this amazing video❤️
Learn cabinet making. My dad was a carpenter. So I started building boxes when I was 14. Built my first pair of A 7's when I was 16. I was always fascinated with horn loaded enclosures. Get yourself a table saw and all the necessary wood working tools.
I like how the videos you make put the transmission line freakhead stuff I do in my head, into a relatively easy to explain and build upon base demonstration of how sound works. It makes it easier to explain why my designs are better than bass reflex, because now they bass reflex a bit better :)
I built 11th order transmission line boxes (2) way back in 1990 for 2 Earthquake 12's. In home use with coils. Amazing bass back then even on low power indoors running on 50 watts rms per channel from a home receiver. Love transmission line boxes.
Aye that first example is awesome! The stick and spring with the air block is a surprisingly good way to represent how sound travels across air molecules. I forget who else did a animated clip showing how the particles dont travel very far but rather bounce off of each other in place
Fantastic video. It’s like I have somehow always known about something like this, but now this video makes it all click together with clear images. Kinda practical lightbulb moment for me. Love it, thanx 👍👍
Was thinking the same thing 😄 “Devin and Austin explore bass reflex designs” Well Devin does, Austin just holds the mics. Like when you “helped” your Dad. Yeah right, you're just holding the flashlight.
Knew most of that, but it was presented in a way that it was easy to show my wife why bass is so tricky to get right, and why I need to select the right cabinet design to get the right kind of bass for our system. Great job on making something so complex easy to understand.
This is very interesting and prob the best explanation I have heard thank you! Was the Binaural mic mono summed? Also what software are you using for your FFT?
Thanks!! The binaural mic is in stereo, but has a low-pass filter on it set to 200Hz because that’s the only important information in the demonstrations. Everything else you hear is from the clip-on mics we’re wearing. The FFT is SignalScopePro
Some deep stuff. Well done! I like how those frequency response patterns are so not unlike mic patterns. Audio is so cool in that it seems so simple, but is actually very deep.
Actually microphones and speakers are, in principle, the same exact thing - they're a linear motor, with a voice coil and a cone. A microphone works exactly as a speaker does, only the microphone cone is so sensitive that it can pick up a voice and take that AC signal through an amplifier which can (hopefully) repeat that same AC sine wave through a speaker.
You can squeeze peak SPL out of a low throw driver by using the tuned frequency of the box made for the sub. Like a strong magnet subwoofer with a shallow, 4inch coil will have tons of magnetic force but cannot do much lower than box design because it cannot control the coil after it leaves the magnets gap. A higher throw sub will usually have more long throw control and the infrasonic bass will play better. I think it was called QT or QTS. High qts like a closed box but a low qts sub will be good in a smaller reflex enclosure and will produce better car audio bass. The higher qts subs will almost always have a better efficiency. I might remember things in reverse like high qts being good for lows but correct me if I'm wrong :)
The upper phase cancellation around the 200-ish Hz mark is caused by the reflection off the back wall inside the cab. This is why making a subwoofer "too deep" can cause problems in the upper bass, and why vented designs that handle midrange line the cab with foam to try and absorb these frequencies.
Wow, that was so interresting! I never thought that there where so much space for optimizations to get a good total response. I always asked myself what magic they use in modern speakers to make them so well sounding. Thnaks alot for this great explaination.
Glad this randomly popped up in my feed… I actually work at a music festival (On the visual side) but I found this fascinating (your title was actually totally suitable ;)
I think that the idea and understanding of bass reflex goes back to the 1930's. The path length (acoustic delay) from the back of the driver to the reflex port determines where the frequency boost occurs.
I registered a design based on a transmission line sub with the AIPO (Australian Intellectual Property Office) many years ago. Unvented Subs are much tighter and don't suffer long Release times... ADSR (Attack Delay Sustain Release). Great Video!
Very interesting video. The best sounding 3-Way speakers I’ve ever listened to are my old man’s original JBL L100’s. This was such a well engineered speaker and box. The bass frequencies even at high volume seem to welcome more power and push air like no other 12” speakers through the port. I also enjoy the Cerwin Vega RE’s, but as a kid being a bassaholic with my brother, we tested so may speakers and subs. I always seem to go back to those JBL’s. They just sound incredible. They set the bar for me and I always compare everything to them.
Actually I did realize this and more. Your clickbait title is a bit arrogant. Your viewers are smarter than you think.
Ok but the original title was going to be "OMG the ONE TRUE SECRET about BASS that the ALIENS TOLD ME!!!"
@@devinlsheets_alphasound Alien tech! I knew it! That explains how you can get such a large driver in such a small box.
We actually do have some of the smartest viewers in the industry btw. Our message inboxes are full of amazing insights and thoughts people have after watching our videos, and it gives us many ideas for future content. Just the way youtube works though, we've found that unfortunately the slightly clickbait titles perform a bit better. You should write a complaint to youtube about it.
@@half-whit5535 yeah that's what he told us too, hated the whole experience. but the condescending ego genre is hot rn with the algorithm so...
@@half-whit5535 Wear Pokémon outfits
I’m from an era when it wasn’t as easy as watching a video or perusing the internet for info, what you showed was knowledge that I learned from quite a few years of reading and research. Quite informative and loved every minute of it.
i used the local library in 1989, Sony SQ Quad, all i needed was a sub and centre speaker then. Oscilloscope did the rest.
Kept the speakers, only updated the DAC.
Math then is the same, you only got better codecs now.
imagine that, im not even a sound engineer and i have all this random knowledge about sound engineering because i watch random youtube videos in my free time
I purchased my first speaker building book from radio shack in 1983. Later the loudspeaker cookbook. Then speaker builder magazine. Learning how the various woofer loading in cabinets mimic electronic filters were invaluable lessons in understanding the marriage of electronics, acoustics and physics of loudspeaker building.
Rip RadioShack and frys electronics
Was gonna say the same thing. Even at local libraries, finding pro audio & studio engineering books wasn’t easy unless I found a way into Portland (25 miles to Portland is a long way for a kid). When I did finally go, that was where I discovered the old (RIP) Powell’s Technical Bookstore which was separate from their main store and only had tech books. But even then, we didn’t have these great videos.
All clearly explained for us who aren't sound engineers, just an average hi-fi enthusiast here learning something new.
It's impressive just how directional that big bass cabinet is, and the science around making it work is fascinating, same for the 2 cans being moved closer and further apart. Thumbs up!
Venetian Snares fan?
@@vargdog6602 Isn't everyone? !
I have been into home theater for 20 years and have built various vented subs, but I never knew about the pressure waves from the port changing direction with relation to the driver. Thank you for sharing this knowledge and taking the time to present it in such a straightforward, yet entertaining way.
everything has its profession to get the best out of it. i like to describe speaker as a racing car. no matter what speaker brand you have, you never get it to perfect for the most part. just like how you put your bass in certain of the room, you get the harmonic effect and one side of the room sound louder than the other side. could be the desk, the chair or computer that distort the sound of the bass. you centered the home theater speaker perfectly where you sit, but the person who sit 4 seat down from you wont theat the perfect 5.1 or 7.1 surround sound experience. just like racing car, each car is tune for specific track once you take it to another track, its not optimized unless you tune for it again
@@BlueRice It just can't be only me who demands more than one Subwoofer? I like four of them and under the bed should it be enough room for a couple who work together as you watch movies laying down... Just be careful they do not redusece eithother...
I think you did good before this however... Basic knowledge and confidence in the process still got you through the job.
This is the explanation I am looking for not available on any other speaker/audio related channel. Salute.
At around the 6:06 mark that "jet engine" shape is called a "venturi".
Like a naturally aspirated carburator. Helps low pressure rush to high pressure uniformly.
My thoughts exactly...
Hello this content should be taught to all sound technicians! It is very educational
Share it with someone!
@@devinlsheets_alphasound unless you want to get the two guys to rap the info to the muzak LOSE IT! it totally ruins a great vid!
He is correct on most of this but he needs to rethink how he describes how a port works. He is kind of correct and kind of wrong.
Ok
@@marxman00 ?
Bass frequencies are a science subject on their own! Excellent video.
I've designed a lot of speakers, including some with pretty esoteric radiation patterns. This is an incredible demo of large room /outdoor bass management, and the explanation of the vent resonance was incredible. Really impressive.
Now I understand what John Atkinson (Stereophile) means when he speaks of the driver at minimum motion at the tuning frequency of the enclosure. I could never envision this in my brain, but your demonstration makes it very apparent.
In my opinion you are the only guy who has uploaded a video for these rare speakers.
You and I are the unique people who purchased them. Anyway
I am an engineer from India, bought this fantastic set of 2.1 with a passive diaphragm sub woofer. Nearly 20 years ago. I have a similar problem.
That thick cable with multiple wires originating from the small satellite speaker and going towards to the sub also develops a loose connection in the connector and starts making weird sounds intermittently, this section too needs to be looked into.
Your video is lucid and helpful thanks for your effort, greetings and best wishes from India
Thank you thank you thank you for playing the sound from the speakers. So many people drone on and talk about speakers, without demonstrating!! You rock!! 😆
This just helped me understand so much about sub frequency response. The cotton ball visual representation made it click! Good stuff here.
this is important work. thank you for demonstrating. Its not about how much you understand the graphs and or how to specifically tune them perfectly. But at least opening the public up to how muchhhhhhh the acoustics, phase and placement matter for sound.
This video was very well put together
I feel like this dude walked to the street and found the first guy and offered him $20 to stand there for 10 minutes. Then I started to watch another video and same with that one. 😂
Putting background music on a video about the sound, while making performing acoustic tests... Genious!
Glad you approve lol
Ironic e?
You did an amazing job teaching a topic so many take for granted! As a rookie going into bass systems and building this really opened my eyes to how bass works, I've watched so much videos about bass but this video? It really takes the cake! Almost feels so illegal to watch a video this good! This is very helpful in understanding how bass works! A very sacred sound! Great video!
I love the raw technical nature of this video. Spent Two years on the road where I was experimenting with subwoofer spacing at half wave to generate / reduce system resonant frequencies to adapt to different locations accoustics. Got a nice spreadsheet out of it that has been very useful over the years
The engineering behind cabinets is just mind blowing. How much would you say that tuning your system every show isn't as much about acoustics vs compensating for the air? Now that I'm watching this multiple times, it makes me think next time I touch a FoH board. I understand acoustics play a major role, but you can tune it ear perfect, but still sound dookie. Bass vibration is weird. High vibrations are weird. Y'all onto something! I need more!
this man so far has been the most knowledgeable and intellectual professor of sound design and engineering ive ever seen over RUclips.
i will learn from you everything there is from you.
I really liked how straight cut and well articulated Devin delivered this video. I usually dont click on or expect to learn anything from "things you dont know about X" videos but this one was very good
Directional sub is so much fun! I done this with a subs suspended up in a dome (together with soundscape speakers all around it at ear level). They were placed at just the right distance and with the right delay to send the frequencies used in the soundscape directly downwards in a cardioid pattern. Those kind of projects are the ones you remember the most (in stead of the normal FOH-installs).
Don’t insult my cell phone! It has all the bass!😂😂
Just the first part about speaker design and tuning frequencies already blew me away. Excellent demonstration of the concepts.
Great video and informative!, the helmholz resonator, or bass reflex uses the concept that the air in the enclosure is physically time delayed in order to exit the port at the same time as the woofer cone is moving forward and as a result, the bass output is doubled, however, the box and port need to be tuned to the resonate frequency of the woofer/subwoofer
Excellent. You were just getting started in the first video. This one was more interresting. 😊
Good things come to those who wait! Part 3 coming soon
After years of building boxes from sealed, to vented, to bass-horn loaded, and simulating those boxes in HornResp, WinISD SpeakerSim, etc, there was nothing in this video that I "didn't realize" but I do really appreciate the cool slow motion and physical representations (the spring/stick/box) done in this video. It's a fantastic way to demonstrate what is happening to the layperson or beginner in DIY audio.
This was definitely an interesting video. The spring stick box thing was physical representation of something that I saw in a paper from Mazda. Using resonant frequencies in an automotive intake to get more air into the cylinders. Changing the length of an intake to have power over a wider rpm range instead of a single peak rpm. It works. I think the Porsche 959 was the first to use something like that. In the diagram it showed using the air as a spring. A mass with a spring on both sides, the mass also being air, the spring is air inside a runner. The mind blowing part is when an engine valve snaps shut, the air stops and builds up on the back of the valve, then springs back into the intake which can help another cylinder with an open valve take advantage of a micro charge. Every little bit counts.
@@pgtmr2713 correction: First patent for variable geometry intake manifold was by Daimler-Benz I believe, in the late 50s. Toyota had their T-VIS which came in 82. My old 88 Mazda RX7 also had 3 butterflies, two smaller and one larger. Not all of these use pressurisation from resonance, like my turbocharged RX7, which wouldn't care, pressure increase due to resonance would probably be negligible as the turbo gave 0.8 bar.
@@JakkeJakobsen Yeah but the T-VIS was dual runner. More about keeping up the velocity. Same as the Taurus SHO. Not sure about the old Benz, but I was thinking more along the lines of something mass produced. Good on Mercedes if they got there first. Never really got into the RX-7 beyond "rotary," but good to see they were using all they could. I had an 88 MR2 4AGE with T-VIS, and have a Mazda KLZE V6 with VRIS. Collected all the intakes for the KL out of curiousity. Similar layout to each, but the only thing they share are the vacuum actuators. At low RPM all runners pull air from the throttle, mid rpm a valve opens and a cross tube opens up so the 2 banks can share some air, High rpm a second tube opens, so all runners can pull from the throttle and 2 other shared crosstubes located close to all runners effectively shortening the path. T-VIS had a 8 runners to 4 cylinders one runner shut down at low rpm increasing the velocity in the one runner for each. Badass 1.6 liter engine. :-D
same for me. This kind of knowledge sharing has and deserve its place on yt.. //My sub specialization in EE studies was electroacoustics at university and been building boxes since my childhood.
@@pgtmr2713 true, thank you very much for sharing and for this video
You would think that background music would interfere with what you are trying for your audience to observe in sound.
Good thing its not about trying to hear the bass through a youtube video, its about how it works and its relationship with air and friction. The point is about 3 feet over your head
Great presentation, a lot people don't think about the changing dynamics in audio, with gasses, humidity, distance, frequency changes.. great stuff
This is the best reprasentation that I have ever seen about subwoofer tuning. If I could I would give this video a million likes I would!!!
I had no idea speaker boxes were this intense... pretty amazing
That's why some subwoofers can literally shake multiple neighborhood from a mile away
@@DigitalSubset no it cant shake anything mile away. Not even with subwoofer. This shit is midbass and it only plays music good
@@fazer5994 I said some can. My system can and is heard a mile away when they’re turned all the way up. 18s in a Tahoe will do it too
@@DigitalSubset yeah you can hear it but it wont shake anything
@@fazer5994 lol *edit: I see he did write "literally" so disregard the lol
Excellent tutorial! All the information is explained and demonstrated in logical order, using clear language. Any needed jargon is explained clearly at first use. This is how all training and educational materials should be structured.
This was actually a very cool and informative video. I started working with PA systems in the early 80s and was positive I knew all I needed to know about subs. I learned something here today about subs I didn't know prior.
Thank you.
wow, the directional bass demonstration really broke my brain. great video!
Devin and Alpha will go down in the books as some of the greats in live audio engineering, pushing the boundaries and explaining each step of the way!
Wow, that was super interesting. One comment I have is that it wasn't always clear what the graphs were showing, and I had to pick it up from context. Once I figured out what the graphs were showing for each section it was great, but between sections the graph was changed (as is appropriate) without the presenter always explaining what they were. For example, sometimes they were relative response, sometimes they were relative phase, sometimes one of each. It would help a lot if there was some label or maybe an intro screen for each part of the video detailing the test setup. For additional context, I am the sound guy for my local church and I picked it up as a hobby from the old dude who _did_ go to school for sound engineering. I am a software developer by trade, and I know about fourier transforms, harmonics, etc. So I am not totally in the dark about the science, but this was a really interesting lesson. Thanks!
Wow!!!! One of the best videos I've ever seen!!! Trust me I've seen alot. Thanks for the hard work and dedication, and for the pasion for audio
Thank you! We always wonder if anyone actually watches these things. Glad to know people are enjoying it
@@devinlsheets_alphasound I will definitely keep watching them .... they are excellent. You really know your stuff and explain it really well 👍
That bit outside about tuning the dispersion pattern using cancellation based on distance...that was pretty neat.
I definitely noticed that live sound is so much cleaner and clearer than it used to be. Great video. Very informative.
Unfortunately most of the music is crap thou..
Great video. I love the explanation of null points in sound. One thing that doesn't get mentioned is that a driver is cone-shaped. So the portion of the driver at its rim, will have a very limited range of motion in contrast to the portion of the speaker closer to the voice coil, which will have the MOST movement. So when looking at air pressure and how that air will move, it's good to understand that air at the sides of the driver will move slower than the air towards the center. So creating a vent that tapers from the source, is essentially mimicking the way the air will flow from the driver.
Part 3 coming soon!
Thank you!
This is REALLY interesting! Can I make a request? Ditch the background music. I found it got in the way of the content. And I really enjoyed the content! Thank you.
Have spent many years around sound. learned more from your hands on technique very refreshing delivery
A complicated subject, well-explained without using math and without leaving out important parts. I'll be referring people to this video. One request: Please don't add background music. It's distracting.
Great presentation!
At 9:03, you are outlining a hyper-cardioid pattern. This is exactly the way a dual diaphragm mic, like a U87, achieves variable patterns.
Amazing to cover that much info about reflex speakers without mentioning Theile-Small parameters. Each box is designed to work with those specific driver physics. Please don’t expect that performance when you replace a driver with whatever is on the shelf locally.
I can't tell how much I learned from this video. Thanks!
Wow! A lot of enrichment of knowledge in a 20 minutes video. Many things are clearer now. Thanks
6:20 the constriction increases velocity as well (yes like a jet would) It could also promote the flow of sound in one direction and not the other. Jaguar's old V12 engines had a trumpet design for the air intake which would allow excellent airflow (for the small diameter at the point on constriction) compared to a normal restriction. The shape accelerated incoming air which reduced the backflow of engine noise via the intake (induction/intake noise).. Thus you had a quiet luxury behavior uncommon for a big performance engine. What design is behind that constriction in the subwoofer would be very important as well.
Venturi effect.
We will have to ask the Nexo team if it’s the Venturi effect which results in the difference in SPL. Even if the Venturi effect is taking place, our intuition suggests that the main reason the SPL increases is because the shape forces the air along the outsides to flow as quickly as the air in the middle through the port length. This reduces the possibility of multiple “layers” of air moving at different speeds which can cause turbulence. Perhaps the Venturi effect, if it is happening here, also somehow contributes to this laminar airflow effect. Maybe this is a good excuse to make another investigative video!
❤ Thank you ! For great bass information . I'm still trying to comprehend it.
Up until this moment, I used to be very proud of the Bose system in my car, the Onkyo home theatre I have at home, the mighty Sony Shake 6 system I take to parties, hell even that wooden box I call " subwoofer" at the back of my other car... .... I was happy & blessed with ignorance.... and… and you just blow it all off, piece by piece, information by information, test by bloody test……...Never felt so naked, so vulnerable and so homeless after a YT video like I feel now………I think I need a hug😞
Incredible content!! Really enjoying learning all this. Surprised it’s free on RUclips!
Share it with someone while it's still free! lol
only free crap here...Need headphones? or better codecs?
you just don't care i see !
The explanation is that simple..... Just because the person REALLY understands the subject. This is what I like the most - complex things become clear.
These videos are priceless, thanks guys.
@2:47: what a great way to demonstrate how air in the tube goes in-phase with the driver! Excellent!
I love the new line array box design.
They are amazing!
@@devinlsheets_alphasound which model is it?
Geo M
That chill track on the background is real subtle
The one about the airflow that flows more smoothly through the narrow passage reminds me quite heavily of the venturi effect that's present on the floor/underbody of the 2022 Formula 1 cars, I assume this follows the same principle?
That’s a very interesting observation, would have to ask the engineers at NEXO. It seems that there would be less pressure during the construction, and whether this is what results in less air turbulence is something they would have to speak for. Our understanding so far has been that the constriction results in a more laminar airflow, where the air along the edges is forced to continue to travel through the port as quickly as the air in the middle, reducing the possibility of incongruent speeds between layers of flowing air, which causes turbulence especially near the edges in a straight port at high air velocity.
I've always wondered how the bass coming out of the vent or port worked. I'm not into pro audio as I am home audio enthusiast. This video actually shows how the air changes direction as the frequency changes and also shows what happens at the subwoofer's resonant frequency. It's really cool to finally know after all these years how it all works!
I love music, I love bass, and I would love to design and make sound systems. I just don’t know how. However this video showed me that it’s a beautiful industry with brilliant engineering knowledge. Now I’m starting to feel like this is what I want to do in my whole life, I want to learn to design these beautiful masterpieces. Thank you for this amazing video❤️
Just by stuff off amazon , and make cabinets yourself ...
Learn cabinet making. My dad was a carpenter.
So I started building boxes when I was 14. Built my first pair of A 7's when I was 16.
I was always fascinated with horn loaded enclosures.
Get yourself a table saw and all the necessary wood working tools.
@@jesse75 I’m currently studying at university, but after that I’m planning to dig into the subject more. Thank you for the advice, I appreciate it!🤝🏼
Best visual illustration I've seen. Thanks for sharing!
I like how the videos you make put the transmission line freakhead stuff I do in my head, into a relatively easy to explain and build upon base demonstration of how sound works. It makes it easier to explain why my designs are better than bass reflex, because now they bass reflex a bit better :)
I built 11th order transmission line boxes (2) way back in 1990 for 2 Earthquake 12's. In home use with coils.
Amazing bass back then even on low power indoors running on 50 watts rms per channel from a home receiver.
Love transmission line boxes.
@alpha sound thank you guys SO much for these amazing video's, they're amongst the best footage that can be found on the entire internet ^^
Guys, this was excellent! Thank you for your hard work in making this video!
3 minutes in and I already learn about the same as in all my audio courses together
lol hope they were free classes
Your method of explanation and demonstration is well-balanced. Thank you, it is very useful.
Aye that first example is awesome! The stick and spring with the air block is a surprisingly good way to represent how sound travels across air molecules.
I forget who else did a animated clip showing how the particles dont travel very far but rather bounce off of each other in place
It's the same way Light so-called travelS it literally doesn't have a speed because it doesn't travel
It has a heatZ simple as that just like sound
Cool, thanks! I haven't been introduced to this info 'till now. I love the thorough walkthrough
I love how much thought was put into illustrating the concept, amazing work!
Fantastic video. It’s like I have somehow always known about something like this, but now this video makes it all click together with clear images. Kinda practical lightbulb moment for me. Love it, thanx 👍👍
good job !
"Just smile and wave boys, smile and wave"
Austin just nods head!!
Was thinking the same thing 😄 “Devin and Austin explore bass reflex designs” Well Devin does, Austin just holds the mics. Like when you “helped” your Dad. Yeah right, you're just holding the flashlight.
Great and informative recording. There are so much relevant content. Looking forward to see part three :-)
Knew most of that, but it was presented in a way that it was easy to show my wife why bass is so tricky to get right, and why I need to select the right cabinet design to get the right kind of bass for our system. Great job on making something so complex easy to understand.
This is very interesting and prob the best explanation I have heard thank you! Was the Binaural mic mono summed? Also what software are you using for your FFT?
Thanks!! The binaural mic is in stereo, but has a low-pass filter on it set to 200Hz because that’s the only important information in the demonstrations. Everything else you hear is from the clip-on mics we’re wearing. The FFT is SignalScopePro
@@devinlsheets_alphasound So sad the software is mac-only =/
Some deep stuff. Well done! I like how those frequency response patterns are so not unlike mic patterns. Audio is so cool in that it seems so simple, but is actually very deep.
Actually microphones and speakers are, in principle, the same exact thing - they're a linear motor, with a voice coil and a cone. A microphone works exactly as a speaker does, only the microphone cone is so sensitive that it can pick up a voice and take that AC signal through an amplifier which can (hopefully) repeat that same AC sine wave through a speaker.
You can feel the passion on the guy explaining, while the other guy just doesnt care. the guy that was listening shouldve been me.
So this is just an ad for Nexo?
You can squeeze peak SPL out of a low throw driver by using the tuned frequency of the box made for the sub. Like a strong magnet subwoofer with a shallow, 4inch coil will have tons of magnetic force but cannot do much lower than box design because it cannot control the coil after it leaves the magnets gap. A higher throw sub will usually have more long throw control and the infrasonic bass will play better. I think it was called QT or QTS. High qts like a closed box but a low qts sub will be good in a smaller reflex enclosure and will produce better car audio bass. The higher qts subs will almost always have a better efficiency.
I might remember things in reverse like high qts being good for lows but correct me if I'm wrong :)
Sounds like you recorded it in mono. Also having music playing in the background makes it harder to hear the effects. Meh.
that slow mo footage was some of the most revelatory material I've seen on the topic. Amazing!
Fantastic demo. I understood these principles, your video makes it visible. Top job.
The upper phase cancellation around the 200-ish Hz mark is caused by the reflection off the back wall inside the cab. This is why making a subwoofer "too deep" can cause problems in the upper bass, and why vented designs that handle midrange line the cab with foam to try and absorb these frequencies.
Wow, that was so interresting! I never thought that there where so much space for optimizations to get a good total response. I always asked myself what magic they use in modern speakers to make them so well sounding.
Thnaks alot for this great explaination.
Glad this randomly popped up in my feed… I actually work at a music festival (On the visual side) but I found this fascinating (your title was actually totally suitable ;)
Been a producer for 4 years and I've never known much of this... great video, learned a lot. Thank you!
it was eye-opening to see how plugging and unplugging the bass reflex port made a huge difference to the bass rumble.
thankyou verymuch guys !
Loved seeing the cotton particles in slow motion, and using the microphones to subtract the driver from the vent was pretty clever!
I think that the idea and understanding of bass reflex goes back to the 1930's. The path length (acoustic delay) from the back of the driver to the reflex port determines where the frequency boost occurs.
3:51 I love how even the dust particles are jamming with the tune.
I knew most of this stuff in theory but the practical examples here really helped my intuitive understanding of these principles.
Cheers cheers cheers 🙏🙏🙏
Phase is so misunderstood and this demystifies it on such an elementary level. Thank you!
thanks for the video, I actually learned something new and got answers to some questions I have been turning over in my head for a long time.
Excellent demo with the spring
that venturi port the V port are amazing
Top top top!!!
Excellent content!
Deeply grateful for the knowledge you're passing through generously!
Thank you very much.
You’re very welcome. Comments like this are highly motivating for us to continue producing such content!
0:45 not going to lie when you pulled the ear muffs out for your microphone, I LOL'ed loudly.
Yup, it's a thing
I registered a design based on a transmission line sub with the AIPO (Australian Intellectual Property Office) many years ago. Unvented Subs are much tighter and don't suffer long Release times... ADSR (Attack Delay Sustain Release). Great Video!
Wouldn’t mind having a chinwag with you if the opportunity arose…
@@chateaudisco1436 Sure ! I'm not sure what I can share with you that may help but by all means, ask away.
Very interesting video. The best sounding 3-Way speakers I’ve ever listened to are my old man’s original JBL L100’s. This was such a well engineered speaker and box. The bass frequencies even at high volume seem to welcome more power and push air like no other 12” speakers through the port. I also enjoy the Cerwin Vega RE’s, but as a kid being a bassaholic with my brother, we tested so may speakers and subs. I always seem to go back to those JBL’s. They just sound incredible. They set the bar for me and I always compare everything to them.
HPM 100's are better.
This is great sound performance illustration. Thanks!
is just obvious that guys behind this video are simply professionals, as sound quality of this video is exceptional