Sign up for the Makers Mob 6 week joinery challenge: rlnk.cc/jhnewjoinerychallenge I know I didn't exactly say what a quadratic diffuser does in this video, but I did in the project build article: ibuildit.ca/projects/how-to-make-a-quadratic-diffuser/ My Speakers and Audio channel: ruclips.net/channel/UCzGbp-rRVNwyFhn9gHoZr5g
Did this treatment to my audio room a few years ago and it made a WORLD of difference. Did a bi-directional though out of reclaimed wood and because I use bipolar speakers the placement was super critical.
Loved the flat painters pad for Poly application! So much so, I'll give my tip: keep some Poly in a ketchup bottle and you'll be quick in applying it by squirting it out. It maximizes working time, since it's not evaporating in an open container such as any pan or even just the original container, and you can just squirt in front of your brush and work very quickly rather than go back and forth from can to surface. Won't beat your pad for large areas like an entire sheet, but perfect for smaller applications you'll be brushing, and you'll find it doesn't go bad with the nib top on: I've pulled it off the shelf 6 months later and after a good shake, it's fully ready to go!
The quadratic residue diffusor or Schroeder diffusor (Schroeder was the scientist who pioneered the development) is typically a box made with a number of wells of different, carefully chosen depths. As a sound wave strikes the irregular surface, instead of bouncing off it like a mirror, it bounces out of each well at a slightly different time. The result is many small reflections spread out in both time and space making is a richer, livelier sound with an enhanced sense of space. Listeners claim that the panels seem to make the walls disappear.
Okay, so what he is making is more likely a quadratic residual diffuser. The math is way over most of our heads but the basic premise is most rooms are not designed with sound in mind so they echo badly and those echos ripple back and forth and that lowers the detail of the sound at your ears. Worse all rooms have a harmonic value which means you can actually get a type of mechanical feedback at the right (or wrong) frequency. So, if you understand the math involved you can calculate the wave lengths which are problematic and design passive diffusers which reduce the echos so that the sound reaching your ears is clearer from any given angle. Or at least that is the way I understand the concept.
@@richardtroell6407 Seems like a good hypothesis Richard. Looking at other places for an explanation (which fail miserably in 'lay man' terms). It seems like the halfway point between an anechoic chamber and a very echoey room (like a squash court). Anechoic chambers are the exact opposite of the 'squash court', they deaden all frequencies and sound doesn't sound right or natural. In a squash court you can't talk with a normal voice for the echo. So maybe they're tuning a room to the range of frequencies they want to use.
From the video description and my opening comment pinned at the top of the feed: "I know I didn't exactly say what a quadratic diffuser does in this video, but I did in the project build article: ibuildit.ca/projects/how-to-make-a-quadratic-diffuser/"
Very nice. Cracked barn wood or a random criss-crossing of slats works extremely well too and can be made to look like amazing wood art. Lots of ways to diffuse!
This is amazing content, this is the two of my hobbies, woodworking and make acoustic boxes, actually I start to woodworking to make some mdf boxes for my car...
you are a very talented craftsman. I would like to do some woodworking but I live in a small flat in London and don't have the space. Maybe one day, but until then I will try to learn about the techniques you use. Big ups!
Nice. I have a quadratic diffusor design that I did for a studio that George Augspurger designed. It is very simple with very minimal ripping you just have to buy 1x2, 1x3, 1x4, 1x6. and only a few pieces are ripped. Saved a lot of time. Anyways, your craftsmanship is great and you definitely have a lot of patience which is rare these days.
I was skeptical, but your version of my shelves + random depth books looks better. I bet your plywood bill would pay for two or three in-home performances by a good jazz ensemble, but you beat the Great Plywood Depression by a few months.
1. What did you use to determine the RT60 time and prime? 2. Why would you have an alcove in the middle? I don't see use of horizontal just 2-dimentional, why is that? I do like your build philosophy...
This looks like a similar process as to the finishing work of Stradivari with his construction of a violin. At a microscopic level their is a honeycomb chamber effect on the violin making the sound of the instrument very distinct and enticing.
I used to work at a company that made acoustic panels like this, we made a huge amount of panels from reclaimed redwood ferry docks for the San Francisco convention centre.
@@garyoldham4449 no! You must use circus peanuts to achieve maximum diffusion in a quadratic orientation. Marshmallows will result in a quintuplic symbiosis. Definitely not the effect we are going for here.
Gave you a like to get you off the devil's number. I like what you're doing here John. Having been in the home theater and automation industry, I'm intrigued to see the outcome and the system going in.
These are often called 2D diffusers because they only scatter the sound to the left and right. I would suggest you add bass absorbing material behind them. I’m curious to see the other treatments you have planned for this room. Should be interesting.
50" wide - the wall is 14' long. Most 55" TV's are less than 49" wide these days. But then this isn't a home theater. I'll watch stuff down there but it's primarily for listening to music.
Hey. Is there a specific reason you are not using a riving knife on your table saw? I've read that those are one of the most basic and easy table saw safety features. I'm just wondering what situations besides using a dado or ultra thin-kerf blade would have you not use one. Thanks.
You mentioned better sound for a TV or movie room at the beginning. Would it help the sound in my living room for movies and sports on the big TV and sound system? The sound in my living room is terrible.
Hi John, I've recently discovered your channel and I'm enjoying all your builds. Have you considered putting a filling such as rockwool in the wells of a QRD diffuser? What would be the outcome if you did? Would you get absorption and diffusion? Thanks
Very impressive! You have great tools and the skill to use them. The sky is the limit to your creations! Any chance you could video the build of a half column diffuser with a flat back to secure to the wall: perhaps 8 feet tall, 2 feet wide, and a radius of 1 foot.
John I would like to ask an unrelated question : How do you heat your workshop ? I live in Ontario and would be very interested in your answer. I enjoy your videos and have built many of your projects using your plans, keep up the good work.
guessing that it bends sound waves, ... bwtfdik either that or creates total harmonic distortion which is also the same as manipulating negative space...
Hey John, new to your channelI! Dig all your A/V booms and gaffers made out of wood instead of the typical metal or fibre glass "store-boughts"! They blend right into the shots. BAD ASS! What did you use to eq the room and formula to know exactly the dimensions of diffusers, please? I've limited knowledge in this audio sculpting and applying it to my studio. Thanks!
With all this discussion about acoustics... made me think... have you ever made any wooden musical instruments? I know you're a Rush fan (I've seen the 2112 shirt)... how about trying your hand at making some Temple Blocks like the ones Peart used to use on Xanadu and The Trees...? just a thought...
This has peaked my curiosity. I've built a geodesic dome in my garden that will serve my family as a music/movie room. Could this design be adapted to fit such a shape?
Yes, you can, but the dome already diffuses the sound by a quadratic "effect" if the speakers arent centered and they are put close to a side. Maybe also diffused too much maybe...
Ever have any trouble with Titebond II or III gluing pre poly'd pieces? Is the PL-P visible in the joint anymore then other glue? Thanks John. I'll go check out your audio channel. Didn't know you had one. :)
I've never used any Titebond products, so I can't comment on how they perform. I've used other brands of yellow carpenters glue and that doesn't like cold. It weakens the joint significantly.
![Noob To Max With DRAGON REWORK In Blox Fruits [FULL MOVIE]](http://i.ytimg.com/vi/LnBMOinoOvA/mqdefault.jpg)
Sign up for the Makers Mob 6 week joinery challenge: rlnk.cc/jhnewjoinerychallenge
I know I didn't exactly say what a quadratic diffuser does in this video, but I did in the project build article: ibuildit.ca/projects/how-to-make-a-quadratic-diffuser/
My Speakers and Audio channel: ruclips.net/channel/UCzGbp-rRVNwyFhn9gHoZr5g
Did this treatment to my audio room a few years ago and it made a WORLD of difference. Did a bi-directional though out of reclaimed wood and because I use bipolar speakers the placement was super critical.
ruclips.net/video/IqBWaXpyad0/видео.html
Ah yes, the old quadratic diffuser. That takes me back to when I was a younger man when I was first introduced to one.......about 7 minutes ago.
Haha, funny guy.
Now... 3years ago..
Loved the flat painters pad for Poly application! So much so, I'll give my tip: keep some Poly in a ketchup bottle and you'll be quick in applying it by squirting it out. It maximizes working time, since it's not evaporating in an open container such as any pan or even just the original container, and you can just squirt in front of your brush and work very quickly rather than go back and forth from can to surface.
Won't beat your pad for large areas like an entire sheet, but perfect for smaller applications you'll be brushing, and you'll find it doesn't go bad with the nib top on: I've pulled it off the shelf 6 months later and after a good shake, it's fully ready to go!
By far the scariest use of a table saw I have seen in a long time. Use a push stick!
Sketched me out for sure
I was waiting for a push bar or a lost finger.
Glad I'm not the only one. Those things scare the bejaysis out of me...
And the push stick was laying on the fence. Apparently it was only used for another video “How to make a push stick you won’t use”.
Here we go again...seek life elsewhere
It is nice that Stephen Root is making woodworking videos now.
Nice shop! Especially that wooden bench vice.
Best thing about this video? Finding out that I also don’t have to be able to make pretty sketch ups to make nice functional pieces... thanks you!
you are a real carpenter. Great job done.
Wow you've really made it look as pretty as a shrine!
Hey, cool trick! Using gaff tape to pull pricetag adhesive off the panels was worth the price of admission all by itself. :D
John I’ve been loving you videos for years. TY
This is the coolest project ever.
The quadratic residue diffusor or Schroeder diffusor (Schroeder was the scientist who pioneered the development) is typically a box made with a number of wells of different, carefully chosen depths. As a sound wave strikes the irregular surface, instead of bouncing off it like a mirror, it bounces out of each well at a slightly different time. The result is many small reflections spread out in both time and space making is a richer, livelier sound with an enhanced sense of space. Listeners claim that the panels seem to make the walls disappear.
Beautiful work my friend 👌
I really thought it was going to tell how it works and what it does
Okay, so what he is making is more likely a quadratic residual diffuser. The math is way over most of our heads but the basic premise is most rooms are not designed with sound in mind so they echo badly and those echos ripple back and forth and that lowers the detail of the sound at your ears. Worse all rooms have a harmonic value which means you can actually get a type of mechanical feedback at the right (or wrong) frequency. So, if you understand the math involved you can calculate the wave lengths which are problematic and design passive diffusers which reduce the echos so that the sound reaching your ears is clearer from any given angle. Or at least that is the way I understand the concept.
Agreed. I mean you should be able to expect any question asked IN THE TITLE to be answered in the video.
@@richardtroell6407 Seems like a good hypothesis Richard. Looking at other places for an explanation (which fail miserably in 'lay man' terms). It seems like the halfway point between an anechoic chamber and a very echoey room (like a squash court). Anechoic chambers are the exact opposite of the 'squash court', they deaden all frequencies and sound doesn't sound right or natural. In a squash court you can't talk with a normal voice for the echo. So maybe they're tuning a room to the range of frequencies they want to use.
From the video description and my opening comment pinned at the top of the feed:
"I know I didn't exactly say what a quadratic diffuser does in this video, but I did in the project build article: ibuildit.ca/projects/how-to-make-a-quadratic-diffuser/"
@@JohnHeisz Ok, thanks for the link.
Dear John. Big thank you! You inspire me. I've signed up for your both channels. All you the best!!!
Very nice. Cracked barn wood or a random criss-crossing of slats works extremely well too and can be made to look like amazing wood art. Lots of ways to diffuse!
I'm ready to move my drums down there. 😝 This is awesome John!!
This is amazing content, this is the two of my hobbies, woodworking and make acoustic boxes, actually I start to woodworking to make some mdf boxes for my car...
I love the mechanical equipment in your office, it's modern and powerful
I did a glue-up yesterday for the first time with "polyurethane construction adhesive". Felt like a John Heisz apprentice! haha
I've never seen that stuff before in any hardware store. Silicone, acrylic sealant, extreme high temp silicone, but none of that, weird.
@@Yonatan24 liquid nails
It's not Liquid Nails. Liquid Nails is a different, much less strong adhesive.
@@Yonatan24 Loctite has one:
www.loctiteproducts.com/en/products/build/construction-adhesives/loctite_pl_premiumpolyurethaneconstructionadhesive.html
Look for PL premium. It’s good stuff and widely available
That looks freaking awesome thanks for the great work.
I need something like this in dining room. Good video
Thanks for the videos, John!
Did this treatment to my audio room and it made a WORLD of difference. Did a Bi-Directional though, out of reclaimed wood.
"Quadratic Diffuser" starts to go tight, it is becoming a work of art. I follow you, keep it up. SL
Glad I'm not the only one who uses that painting technique on the edges 🙃
That's some nice plywood
When making a hollow structure like that, it's important to make sure it's perfectly airtight, or you'll cause sound issues.
you are a very talented craftsman. I would like to do some woodworking but I live in a small flat in London and don't have the space. Maybe one day, but until then I will try to learn about the techniques you use. Big ups!
Great videos. Very useful tips
This is definitely a cool looking build, John.
Nice. I have a quadratic diffusor design that I did for a studio that George Augspurger designed. It is very simple with very minimal ripping you just have to buy 1x2, 1x3, 1x4, 1x6. and only a few pieces are ripped. Saved a lot of time. Anyways, your craftsmanship is great and you definitely have a lot of patience which is rare these days.
Hey! I’d love to get a hold of that design plan so I can build some!
Man I’m really digging this new content!!
This was awesome. Thank you
so freaking cool!
I was skeptical, but your version of my shelves + random depth books looks better. I bet your plywood bill would pay for two or three in-home performances by a good jazz ensemble, but you beat the Great Plywood Depression by a few months.
Nice Work!!!! Thank You!!! 👍😎
1. What did you use to determine the RT60 time and prime? 2. Why would you have an alcove in the middle? I don't see use of horizontal just 2-dimentional, why is that? I do like your build philosophy...
This looks like a similar process as to the finishing work of Stradivari with his construction of a violin. At a microscopic level their is a honeycomb chamber effect on the violin making the sound of the instrument very distinct and enticing.
I used to work at a company that made acoustic panels like this, we made a huge amount of panels from reclaimed redwood ferry docks for the San Francisco convention centre.
Hey! I’d LOVE to make a few of these for my Recording studio. How do I get the plans for this? I appreciate you and I look forward to your reply.
People are still waiting to find out what a quadratic diffuser is.
I think it's quite obvious that it diffuses, much like other diffusers, but in a quadratic way. You're welcome.
@@keithklassen5320 Rhombohedric sound will become quadratic sound upon seeing the diffuser. Got it.
@@stianyttervik9070
What if I fill it with marshmallows will that help?
@@garyoldham4449 no! You must use circus peanuts to achieve maximum diffusion in a quadratic orientation. Marshmallows will result in a quintuplic symbiosis. Definitely not the effect we are going for here.
Would love to see the acoustic measurements when you are finished .👍
Very nice. Have seen anyone operating the impact driver with precision
Gave you a like to get you off the devil's number. I like what you're doing here John. Having been in the home theater and automation industry, I'm intrigued to see the outcome and the system going in.
For more rudimentary diffusion, try bookcases and random books.
Could you hqve used a pin nailer instead of the brad nailer?
Can you please add the Diffuser width and Theoretical depth of this diffuser ?
Very Cool Brother👍
Awesome! One problem I have with this. Basement. Not in my world. You would need to make it from mold treated cement.
Hi Guys, I cant find it, what is the well width in that project?
I don't understand how it works yet, but it sure looks awesome
I'm not into acoustic engineering but I find these panels make an interesting design.
Agreed. But I would still have liked to learn something about the principle behind the design.
These are often called 2D diffusers because they only scatter the sound to the left and right. I would suggest you add bass absorbing material behind them. I’m curious to see the other treatments you have planned for this room. Should be interesting.
Sharp-looking build. How did it sound in the end?
That's amazing, I just finished a BEM simulation of QDRs for a project at engineering school 😅 insane timing
Pretty cool
Is the applicator pad your preference for applying water based poly? I tend to get bubbles with brushes or fine napped rollers.
Is this better than the cone of silence ?
How big is the TV opening? Is it sized for a 55" ? The photo makes it look a bit small so I'm thinking I'm misjuding it
50" wide - the wall is 14' long.
Most 55" TV's are less than 49" wide these days. But then this isn't a home theater. I'll watch stuff down there but it's primarily for listening to music.
Can this be painted with acrylic car paint ?
Hey. Is there a specific reason you are not using a riving knife on your table saw? I've read that those are one of the most basic and easy table saw safety features. I'm just wondering what situations besides using a dado or ultra thin-kerf blade would have you not use one. Thanks.
You mentioned better sound for a TV or movie room at the beginning. Would it help the sound in my living room for movies and sports on the big TV and sound system? The sound in my living room is terrible.
Hi John, I've recently discovered your channel and I'm enjoying all your builds. Have you considered putting a filling such as rockwool in the wells of a QRD diffuser? What would be the outcome if you did? Would you get absorption and diffusion? Thanks
Pretty interesting work, John!!! 😃
And it looks pretty nice!
Stay safe there with your family! 🖖😊
Beautiful
Thank you.
Very impressive! You have great tools and the skill to use them. The sky is the limit to your creations! Any chance you could video the build of a half column diffuser with a flat back to secure to the wall: perhaps 8 feet tall, 2 feet wide, and a radius of 1 foot.
What are the messurements?
What is the width of the wells ?
Did you not have an issue with raised grain with water carried varnish?
another great project.
George Lucas doing woodworking is exactly what i needed rn
John I would like to ask an unrelated question : How do you heat your workshop ? I live in Ontario and would be very interested in your answer. I enjoy your videos and have built many of your projects using your plans, keep up the good work.
Nice !!!
Why polyurethane, instead of varnish?
guessing that it bends sound waves, ... bwtfdik either that or creates total harmonic distortion which is also the same as manipulating negative space...
Would it make any difference in their effectiveness if the panels were installed horizontally?
They would scatter the reflections vertically if mounted horizontally.
been meaning to for a couple of years now but your videos dont come up in my feed too often....SUBSRIBED AND HIT THE BELL!!
Hi John, I am going to make one exactly as yours, may I have the well width? BTW, do well width and height make difference?
I meant the diffuser height.
Hey John, new to your channelI! Dig all your A/V booms and gaffers made out of wood instead of the typical metal or fibre glass "store-boughts"! They blend right into the shots. BAD ASS!
What did you use to eq the room and formula to know exactly the dimensions of diffusers, please? I've limited knowledge in this audio sculpting and applying it to my studio. Thanks!
So why not just finish both panels on both sides, helps preserve the wood, & avoids any possible mix ups ?
Man I want to do all of this... someday...
Awesome.
Sweet setup. Love the ply look. How does it sound?
Thats looks kool!!!!
Hey John,
Did you use a calculator for your wells? If so, I'm glad you went so deep with them, a lot of people make them shallow.
I want to build these for my studio
Thanks for sharing that!
With all this discussion about acoustics... made me think... have you ever made any wooden musical instruments? I know you're a Rush fan (I've seen the 2112 shirt)... how about trying your hand at making some Temple Blocks like the ones Peart used to use on Xanadu and The Trees...? just a thought...
This has peaked my curiosity. I've built a geodesic dome in my garden that will serve my family as a music/movie room. Could this design be adapted to fit such a shape?
Yes, you can, but the dome already diffuses the sound by a quadratic "effect" if the speakers arent centered and they are put close to a side. Maybe also diffused too much maybe...
@@OlivierMyre88 thanks for replying. I'll have to see how it performs once everything is installed.
What are the other panels with holes?
Good stuff
Not clear! What is it for?
Ever have any trouble with Titebond II or III gluing pre poly'd pieces? Is the PL-P visible in the joint anymore then other glue?
Thanks John. I'll go check out your audio channel. Didn't know you had one. :)
I've never used any Titebond products, so I can't comment on how they perform. I've used other brands of yellow carpenters glue and that doesn't like cold. It weakens the joint significantly.
@@JohnHeisz How is the yellow glue at pre finished poly glue joints? Or was the PL the only thing that stick the poly together? Thanks.
Woodworking glue only sticks to wood, paper or leather. PL sticks to everything, especially clothes :)
@@JohnHeisz LOL!! Yep!. Thanks John. I'm a metal guy that muddles his way through wood work, so you are a big help!
neat video
awesome!!!
What were you doing with the black tape? You stuck it on plywood then pulled it off?
He was removing the glue left over from pulling the sticker.
Thank you
As a soundfreak, and I did some soundproof dead studios build myself I’m very curious what sound equipment you’re using:) keep up the good work!