DIY QRD diffuser

[SaSi_SiDi]

Here's an animated description on making a DIY QRD.
YouTube - 1D QRD Acoustic Diffusor

I liked the construction idea, but enjoyed the animation quality more.

[Ethan Winer]

Yes, very cool. I bet the video took longer to make than the diffusors.

--Ethan

[hefuriousrapper]

Originally Posted by SaSi_SiDi

Here's an animated description on making a DIY QRD.
YouTube - 1D QRD Acoustic Diffusor

I liked the construction idea, but enjoyed the animation quality more.

do you know where the pdf is for download?

i really want to build one now



thanks

[Glenn Kuras]

Did you notice at the end it says "It took us one week to build". lol lol

[Glenn Kuras]

Originally Posted by hefuriousrapper

do you know where the pdf is for download?

i really want to build one now



thanks

Let me give you a word of caution. We are getting into building more and more wood products (new all wood QRD coming soon) and I have learned that using hobbyist tools makes things VERY hard. Honestly to make a QRD that the wells have a tight fit (important) it is best to use a CnC to do the cutting. You may want to see if there is someone locally with a CnC to do your cuts. If not maybe someone with a table saw that has a digital read out.

[andrebrito]

Jesus , 1 week, that is crazy. Ok it is prime 23, sure it looks great but this is purely DYI, stuff like this would not survive in the industry.

When the company I work for built my own diffusers we had do 100 units in 2 weeks for a concert hall and we were just using 2 or 3 persons to manufacture them, so we had to come up with a quick method of assembling them

[elmolemon]

Originally Posted by Glenn Kuras

We are getting into building more and more wood products (new all wood QRD coming soon)...

Nice! Any date yet? Will these also be available from your EU/UK-plant?

[Glenn Kuras]

Originally Posted by elmolemon

Nice! Any date yet? Will these also be available from your EU/UK-plant?

Not sure yet. We still are working out a few details. Here is picture though.





As far as the UK, our plan is to offer them over there as soon as possible. But we will start with the states.

[elmolemon]

Thank you Glenn for your fast answer! They look nice. It would be great to have them in the EU, too..

[collo]

Originally Posted by Glenn Kuras

Let me give you a word of caution. We are getting into building more and more wood products (new all wood QRD coming soon) and I have learned that using hobbyist tools makes things VERY hard. Honestly to make a QRD that the wells have a tight fit (important) it is best to use a CnC to do the cutting.

I agree - after making some myself I can report that they do take a helluva long time to build. Also you will use more glue than you thought possible!

From the pics, your new diffuser looks very nice!

[Glenn Kuras]

Originally Posted by collo

I agree - after making some myself I can report that they do take a helluva long time to build. Also you will use more glue than you thought possible!

From the pics, your new diffuser looks very nice!

Thanks! We have a one more test piece to run and we should be good to go. My goal was to manufacture all the pieces in house, but one small one seems to work better on a larger CNC format. Just waiting on the sample.
BTW use pocket screws. Glue I guess will work but if that thing ever fell off the wall it might fall apart.

[elmolemon]

How deep will the new wooden QRD be?

Can you already say something about the low-frequency cutoff-point?

[Glenn Kuras]

Originally Posted by elmolemon

How deep will the new wooden QRD be?

Can you already say something about the low-frequency cutoff-point?

The GIK QRD Pro is 7 root diffusor design that begins scattering at approx 350Hz and offers effective and even diffusion up through 3 kHz. The QRD Pro offers additional scattering up to the upper limit of approximately 7 kHz.

Size: 19.5"x46.5"
Thickness is 5.75"
Weight: 35 pounds

[Sebg]

I was curious so I commissioned a workshop that does expanded polystyrene (EPS) work to make some diffuser shapes. They ended up about $100 each.

There are three.
1st is 2D 600x600x200mm
2nd is the simplest N=7 QRD, 1200x600x150mm
3rd is the same but without fins as I considered the possibility of adding these as 6mm MDF later.
The EPS fins are 15mm and the grade of EPS is VH, 28kg/m^3.

There are some minor fit and finish issues, to be expected for a first attempt, and the fins are probably just robust enough for actual use, provided they don't get a hard knock, but overall I thought they turned out quite well. And took me only the design time to make.

[Bill Lagos]

Originally Posted by Glenn Kuras

Not sure yet. We still are working out a few details. Here is picture though.





As far as the UK, our plan is to offer them over there as soon as possible. But we will start with the states.

Hello Glenn!

UK, please ASAP!

Bill

[elmolemon]

Originally Posted by Bill Lagos

UK, please ASAP!

+1

Any idea concerning the pricing yet?

[Glenn Kuras]

Originally Posted by Bill Lagos

Hello Glenn!

UK, please ASAP!

Bill

Trust me we are working on it!! Actually working on just getting the thing out in the US also!!

[johndykstra]

watching that video, the construction is confusing to me. It appears they are simply nailing a well bottom to a fin, and repeat. But how do you nail two assemblies together? How do you fit a nail gun between two fins?

[Glenn Kuras]

Originally Posted by johndykstra

watching that video, the construction is confusing to me. It appears they are simply nailing a well bottom to a fin, and repeat. But how do you nail two assemblies together? How do you fit a nail gun between two fins?

I guess you could use a nail gun up until the last few wells, but your going to end up with a bunch of nail holes. Sure you could use wood putty but you still would see it. Seems like a lot of effort for something that would not look 100% pro.

[johndykstra]

I don't think you can.

visualize the process... you run into difficulty nearly right away... the second well bottom.

[Glenn Kuras]

Originally Posted by johndykstra

I don't think you can.

visualize the process... you run into difficulty nearly right away... the second well bottom.

I see what you are saying. thumbsup

[Glenn Kuras]

Originally Posted by elmolemon

+1

Any idea concerning the pricing yet?

Going to nail down the pricing next week. BTW today Carlos (our production manager) and myself worked (it is a holiday but we worked) on the production. This picture proves I still can get my hands dirty!! One pallet DONE!

[tonio]

Originally Posted by Glenn Kuras

Going to nail down the pricing next week. BTW today Carlos (our production manager) and myself worked (it is a holiday but we worked) on the production. This picture proves I still can get my hands dirty!! One pallet DONE!

Dedicated....comes to mind- I hope you had some to enjoy some Turkey time.


Are the fins 1/4" ?

+1 for the time it takes to make a 1D QRD.

[tonio]

My N11 build before finish poly. I'll never do the finishing coat after build again !

[Glenn Kuras]

Originally Posted by tonio

Dedicated....comes to mind- I hope you had some to enjoy some Turkey time.


Are the fins 1/4" ?

+1 for the time it takes to make a 1D QRD.

Oh yea we did Turkey on Wednesday.

Yes the fins are 1/4".

[Glenn Kuras]

Originally Posted by elmolemon

+1

Any idea concerning the pricing yet?

All the info is here.
http://www.gearslutz.com/board/new-p...-diffusor.html

[ytass]

Originally Posted by Sebg

I was curious so I commissioned a workshop that does expanded polystyrene (EPS) work to make some diffuser shapes. They ended up about $100 each.

There are three.
1st is 2D 600x600x200mm
2nd is the simplest N=7 QRD, 1200x600x150mm
3rd is the same but without fins as I considered the possibility of adding these as 6mm MDF later.
The EPS fins are 15mm and the grade of EPS is VH, 28kg/m^3.

There are some minor fit and finish issues, to be expected for a first attempt, and the fins are probably just robust enough for actual use, provided they don't get a hard knock, but overall I thought they turned out quite well. And took me only the design time to make.

Attachment 203067

Hello,

Which workshop did you commission for the EPS diffusers?
How well did they perform? Were you able to compare with an all-wood design?

Cheers

[Sebg]

I am in Sydney Australia (if that helps you). Expanded Polystyrene (EPS) Insulation, Underfloor & Wall Insulation Suppliers and
A & C POLYSTYRENE P/L, Wetherill Park, NSW 2164

In terms of finish, latex paint makes them look much better than 2 coats of water-based paint. In terms of tests I defer to Jens' workwhich shows they are almost as reflective as wood.