How To Build An Acoustic Quadratic Diffuser - DIY

This video will show you, step-by-step, how to build a quadratic diffuser. This video is quick and to the point. A quadratic diffuser is a type of acoustic treatment that spreads sound energy equally throughout a room. They are used to get rid of echoes. Acoustic Diffusers are great for rooms with reflection problems. A room with a lot of reflections will have echoes and phasing issues. Acoustic Diffusers can be used in recording studios, home theaters, conference rooms, churches, or any room that requires a controlled sound. They can also be used as wall art. The most common place to mount an acoustic diffuser is on the wall behind the listening position but they can be placed in other areas of a room with great effectiveness too. Covering the wall behind the listening position with multiple diffusers will instantly improve the sound quality in any room.

[@urbanfabric]

You make it look so easy to build! Thanks for sharing your knowledge.

[@RoostersRecordingStudio]

You're welcome. Take your time. It's not that bad. Thanks for watching.

[@blauerkomischeradler1631]

What is this diffuser behind the couch. Looks very good visually. Is there a video about it?

[@dt3268]

great job presenting. Neat. Clear. Precise.

[@rened9933]

Very thorough and understandable video. Thank you 👍

[@audiononsense1611]

I know this is a DIY project however one must know a few things to determine the primes (1/2 and 1/4 wavelengths) of the problem frequencies. Especially for a studio!! It's critical... Hope this helps...

[@ELISHACAEZ]

This is amazing thank you so much for your time

[@ChanokchaiChauychoo]

thanks this is such a very nice helpful video

[@bdisaac1]

Thanks.

[@itikutok6568]

Absolutely brilliant! Thanks a ton!

[@decaf77]

Great video thank you for sharing!

[@RoostersRecordingStudio]

@Nick Thanks for watching. You're welcome.

[@stasborsuk4465]

Спасибо, мне кажется, отлично получилось!

[@audiomez]

Straight runs of obsolete garage door tracks “wheel locked” using two sided reflection diffusers yield an interesting “astatic” array of of dampening or mid pitched rejection depending on which azimuth the reflectors are turned.

[@ahmedrezaie4920]

Hey man great video and thanks for sharing.! With this particular model which frequencies are we targeting to defuse ? Thanks 🙏

[@RoostersRecordingStudio]

@Ahmed Rezaie Thank you I appreciate that. This model is most effective from 1.3K - 1.7K. The coefficient is .64 at 1.5K. Thanks for watching.

[@briandamkroger3897]

Would the performance be significantly degraded if I built it out of dimensional lumber, where the 1” X 2” is actually 3/4” X 1-1/2” and the 1” X 4” is 3/4” X 3-1/2” ? True size boards have proven difficult to find. Thanks. I love the video and project. Simple and easy, even for me. Brian

[@sean_heisler]

I see Alex hasn’t responded yet but I’m inclined to think that when he stated the sizes in the video he was using the common dimensions as opposed to the true dimensions - the sizes you mentioned.

[@audiononsense1611]

Read my reply 1st...

[@mattmarantz4863]

Awesome job! Would you ever make these for other people?

[@RoostersRecordingStudio]

@Matt Marantz Thank you very much. I definitely want to sell these in the future. Wood is expensive right now. So, I have to figure out how to make it affordable. Thanks for watching.

[@RomanWaves]

6:28 The Bob Ross of Room Acoustics

[@BenzG1L]

Are these board sizes actual dimensions or 1/2’’ less per side as per any construction wood?

[@michaelyolch79]

Well, this inspired me to just buy them. 😂

[@draganfilic8127]

HEJ alex thanks for the detailed details for making the diffuser, I'm interested in what wood the boards for making must be made of or it doesn't matter whether it can be done with OSB boards and I'm still interested in my room is 15 m2 a wall that is about 3.5 m away from the place of listening nice greeting

[@RoostersRecordingStudio]

You could use OSB but keep in mind how heavy that will be. Also, I think they use a specific glue for joining OSB. I would use select pine but OSB will work. Thanks for watching.

[@draganfilic8127]

@@RoostersRecordingStudio Thank you for your reply

[@RoostersRecordingStudio]

@Dragon Filic No problem

[@laurabrown9192]

Acoustic Foams are used for Echo & Acoustic Curtains are used for Soundproofing SoundProof-Curtains.me

[@mozdedo]

Which QRD number ratio is this?

[@VenVile]

Great job. Do these have 7 or 6 wells?

[@RoostersRecordingStudio]

@IamVenVile I have multiples of these throughout the room. Some are odd numbered wells and some are even. The biggest ones I have are almost 7ft tall with 9 wells.

[@bennydrumming...2339]

My listening area is abt 25/40. How i can calculate to build diffuser .i had done with absorbers need to work on mids n highs

[@kendallhoulder5139]

Thank You

[@RoostersRecordingStudio]

@Kendall Houlder Thank you for watching.

[@gerardlake]

And what you recommend for Bass

[@RoostersRecordingStudio]

@Shot Master J I would use high density foam for low frequency problems. You need to absorb the sound energy. Start with the problem areas first (corners) then treat the walls. I used this site when I was building the studio. They have amazing prices and some cool stuff. foamforyou.com/style-g-361.html

[@laurabrown9192]

Acoustic Foams are used for Echo & Acoustic Curtains are used for Soundproofing SoundProof-Curtains.me

[@SteveWhitcomb]

1 x 4 actual thickness or 3/4 x 3 1/2 nominal?

[@sean_heisler]

Alex - if all boards are cut down to 41” how come one needs to buy 6’ boards? Wouldn’t 4’ (which is 48”) boards suffice for cutting down to 41”?

[@emmanuelbonilla4375]

Awesome video Alex. I will build these as they are what I'm looking for. Thanks! Also, can I paint these to the color of my choice, will it effect any performance? Thanks again

[@ELISHACAEZ]

Paint might make it work even better

[@gabrielzapata2569]

Hey Alex! Great video thanks for the detailed and clear info. Do you know if there is any calculator that I could use to design on of theses diffusers for a specific height and width of the frame? Thanks!

[@RoostersRecordingStudio]

Take a look at QRDude on the app store. Hope this helps.

[@laurabrown9192]

Acoustic Foams are used for Echo & Acoustic Curtains are used for Soundproofing SoundProof-Curtains.me

[@tj_vollmer_408]

What are the over all specs ? Width and height

[@corianteedwards6321]

what type of diffuser is that in the right corner of the room? The pitch black one

[@bobbystefano]

what is the final size?

[@Gholhovallahoahad]

Hello.. for a small room with dimensions: ceiling 2 meters __ width 3 meters __ length 6 meters __ which is completely insulated with stone wool... what model and depth of diffuser would you recommend me to make??? Please help me, thank you

[@95behzad]

Could this work with extruded polystyrene (xps) to reduce costs & weight? Painting it should reflect some some of the higher frequencies

[@RoostersRecordingStudio]

@elixr I don't see why not as long as it's not too porous. Diffusers are usually made of denser materials but good idea to reduce weight. Most paints will destroy polystyrene because it doesn't stand up to chemicals well so try a test piece first. Also, you will need a special glue to get the pieces together. Give it a try. Thanks for watching.

[@JonnyParker-]

Hey did you try making it with that material man? Curious to know how it ended up as i was thinking along similar lines. Also has anyone tried Balsa wood or is it not suitable ?

[@impulseproman]

am looking at the panel you have behind your desk

[@RoostersRecordingStudio]

@impulseMusic Cool. I built that when I was at FullSail University. It's diffusion and redirection in 1. I've had a few people ask if I could show how I made it. I might one day. It's expensive, time consuming, and a bit tricky to put together. Thanks for watching.

[@gerardlake]

What's weight of it

[@RoostersRecordingStudio]

@Shot Master J The one standing up at the end is about 45lbs. If you make it with the dimensions I give in the video it's a little smaller and weighs about 35lbs. I have 2 that are 3ft by 6ft and they weigh a good 70lbs.

[@gerardlake]

@@RoostersRecordingStudio Amazing work and Nice Studio!!!!

[@RoostersRecordingStudio]

@Shot Master J Thank you. I really appreciate that. Thanks for watching.

[@laurabrown9192]

Acoustic Foams are used for Echo & Acoustic Curtains are used for Soundproofing SoundProof-Curtains.me

[@alejandroalfonsoofficial]

what are the frequency range?

[@RoostersRecordingStudio]

@Alejandro Alfonso 1K - 3.5K they are limited and don't work well in small rooms. They can be effective down to 100Hz but the wells will have to be much deeper. There are free calculators online you can use that will tell you how deep to make the wells for your room.

[@chinmeysway]

pretty sure QRD requires math for varying the depths...

[@Mattingrammusic]

I don’t think that’s 6’ bro

[@Tamperkele]

It is. You should see the guy in real life. He's so huge that the boards just look small.