Home-made Skyline Diffusor

[datune]

Originally Posted by jeep

well i depends on where you're putting it, and what result you wish to achieve
so for example in a control room, you want absorption in the front to get rid of the first reflections from your monitors, and diffusion on th back wall, to breathe some life back into the room. this creates a "reflection free zone" when seated at the correct position within the room

every room is different, and different rooms within studios serve a different purpose, which calls for different acoustic treatment
its not as straight forward as most of us think or would like it to be


do you plan on treating one of your rooms? or are you just interested in acoustics?

thankksssss

Hey jeep ;-)

I'm generally interested in learning more about acoustics. I have created a RFZ zone in my room, but at the back there's currently two broadband absorbers. I'm not sure if I would like the sound of a diffusor (hard to know since I can not test it), but if you have watched the video from Ethan about diffusors, personally I thought the most natural sounding one was the last one, with the guitar sitting in the room, and the absorption panels a good distance away.

From all I could gather so far, I'd be inclined to think that generally absorption for smaller rooms MAY be better then diffusion, but obviously this is just from what I've read.

That's the piece of the puzzle that's still missing for me, trying to figure out when it's best to use diffusion vs absorption.

I do know one thing though, no single piece of equipment on this planet will improve sound quality so dramatically as acoustical treatment, at least that's my experience, but for sure you know all that , otherwise you wouldn't get your hands sore

Looking forward to seeing this finished and reading your results as to whether the outcome is as expected.

[jeep]

Originally Posted by datune

Hey jeep ;-)

I'm generally interested in learning more about acoustics.

Howdy partner

If you've got a keen interest for acoustics, I would highly recommend getting "The Master Handbook of Acoustics: Fourth Edition" by F. Alton Everest
It's very, very helpful and informaive

I have created a RFZ zone in my room, but at the back there's currently two broadband absorbers. I'm not sure if I would like the sound of a diffusor (hard to know since I can not test it), but if you have watched the video from Ethan about diffusors, personally I thought the most natural sounding one was the last one, with the guitar sitting in the room, and the absorption panels a good distance away.

Like gear, methods etc. the sound of your control room should be the way you want it to be. Some people like completely dead control rooms, others totally live. The reason for absorption at the front and diffusion at the back is to give you a balanced, natural room to work in. If you were to mix in a dead room, you may add too much reverb or effects. if you were to mix in a live room you may end up creating a very boring or dull mix. The aim is find a balance between the two, which should enable you to create a mix that translates well when played back in the real world.

From all I could gather so far, I'd be inclined to think that generally absorption for smaller rooms MAY be better then diffusion, but obviously this is just from what I've read.

From what I have read also, this is true. But without having years of experience and research, unfortunately I can't answer this
A lot of bass trapping seems to be the most common treatment for small rooms..
Another thing is that diffusion generally requires a fair amount of space to work, but this really depends on the design
In my case, my back wall is only just over 1 metre behind me. The diffusor that Jason designed for me should work under this condition

What are the dimensions of your room?
Are there any windows?
Where are your speakers placed?

That's the piece of the puzzle that's still missing for me, trying to figure out when it's best to use diffusion vs absorption.

Try using absorption everywhere until the sound is more focused and becomes clearer. Then, if it sounds too dead, add some diffusion on your back wall, back sides and maybe even back ceiling.

I do know one thing though, no single piece of equipment on this planet will improve sound quality so dramatically as acoustical treatment, at least that's my experience, but for sure you know all that , otherwise you wouldn't get your hands sore

Looking forward to seeing this finished and reading your results as to whether the outcome is as expected.

Thanks for your interest
I hope this helps and doesn't steer you in the wrong direction.. I'm sure one of the other guys will correct me if I've said anything wrong anyway


The process of placing all the blocks in the right location one by one..
(in reverse)













Queens Of The Stone Age - Lullabies to Paralyze
the perfect album for doing anything


I'm currently gluing the balsa blocks to the base.

[datune]

Hey jeep ;-)

Below is a drawing of my room and the current treatment (I realize there is lots of room for more treatment)

But hey, I don't mean to pollute your thread ;-)

I'm really curious how it's going to affect the sound in your room once finished.

[skatingbasser]

Hey Jeep,

Could you write me a quick summary of what all was involved? I don't doubt for a second the amount of work you did, I'm just trying to understand where all the time went.

I thought you were numbering the blocks based on depth, plotting the squares on the base in numerical order, and using those charts to organize which blocks go where... but the squares on the base aren't in numerical order, and the numbering system for the blocks don't appear to match with depths.


Sooo....


Whatcha doin' there, man?

[jeep]

just waiting for the liquid nails to dry
almost time to go on the wall!










oh and the colour scheme,
don't ask.

[datune]

So how does it sound?

[jeep]

Originally Posted by datune

So how does it sound?

after a quick listen i honestly couldn't hear much difference

about 2 hours later i sat down and gave it some more though/listening and began to notice a clearer, more natural sound
i could best describe as this:
imagine you're at the beach, swimming in a dense liquid, like mud. full of gunk and seaweed. you then come to a section where the water is clean and clear - it is much easier to swim in, and the ocean feels bigger. you are free

does my analogy make sense?
haha

[rarseman]

Originally Posted by jeep

just waiting for the liquid nails to dry
almost time to go on the wall!










oh and the colour scheme,
don't ask.

[jeep]

fin.

[audiovisceral]

Originally Posted by jeep

fin.

paint is great. very modern art!

ps. qrd's are waaay easier

[bitman]

And the sound now?

[Jabbaz]

I made a 460mmx460mm one of these out of cedar, and my longest pieces were 350mm. Needless to say it was a heavy sucker... and a challenge to hang.

Jeep:

Did you have to plane the balsa, or was it all straight and consistent in dimensions? My issue was that the first pieces I inserted lined up pretty well but the dimensional differences accumulated, and by the end the alignment got ugly.

I found the cutting and organizing didn't take too long... the most time consuming part was gluing.

Also, I read somewhere that having a frame round the exterior reduces the diffuser's low frequency performance. Can anyone confirm?

[T.H.Reid]

F**KING exellent, mate!!!

[Ben Brayer]

That looks awesome!

[Lissajous]

Awesome

[jeep]

Originally Posted by datune

Hey jeep ;-)

Below is a drawing of my room and the current treatment (I realize there is lots of room for more treatment)

But hey, I don't mean to pollute your thread ;-)

I'm really curious how it's going to affect the sound in your room once finished.

If i were you i'd move everything back a little bit, so your sitting position is almost in the middle.
it seems that you've taken into account balance of sound - equal distances of monitors etc which is good
maybe place your sub in the middle of your 2 monitors (on the floor of course). i can't imagine the current location being good for it.. corners = build up of bass frequencies
your 1st reflection points seem to be covered. wonderful

my recommendation is to put some diffusion on the back wall and the rear back walls.
i had some clients over on the weekend and they made the comment that the room sounded partially dead, but not too dead. a good, even and comfortable balance between live and dead sound was present
you'll never understand until you give it a try

Originally Posted by bitman

And the sound now?

magical

Originally Posted by Jabbaz

I made a 460mmx460mm one of these out of cedar, and my longest pieces were 350mm. Needless to say it was a heavy sucker... and a challenge to hang.

Jeep:

Did you have to plane the balsa, or was it all straight and consistent in dimensions? My issue was that the first pieces I inserted lined up pretty well but the dimensional differences accumulated, and by the end the alignment got ugly.

I found the cutting and organizing didn't take too long... the most time consuming part was gluing.

Also, I read somewhere that having a frame round the exterior reduces the diffuser's low frequency performance. Can anyone confirm?

not too sure on the frame regarding low diffusion loss
i hope not!!

yeh gluing took a long time
i took A LOT of time making everything was as accurate as possible
and even after that i had some problems at the end
i had to cut/sand some of the outer row blocks (only by about 2mms though)

the next one i make will probably be on foam board or something so it'd be lighter than a picture frame!!


cheers everyone

[jeep]

Originally Posted by skatingbasser

Hey Jeep,

Could you write me a quick summary of what all was involved? I don't doubt for a second the amount of work you did, I'm just trying to understand where all the time went.

I thought you were numbering the blocks based on depth, plotting the squares on the base in numerical order, and using those charts to organize which blocks go where... but the squares on the base aren't in numerical order, and the numbering system for the blocks don't appear to match with depths.


Sooo....


Whatcha doin' there, man?

made the frame
measured the 323 blocks to length
cut them and numbered them once cut - there were approx. 30 different lengths, each block having its own individual number or position.
sanded each block
lined up and glued each block
spray painted

took about a week (part time)

[winvbass]

Originally Posted by jeep

Queens Of The Stone Age - Lullabies to Paralyze
the perfect album for doing anything


I'm currently gluing the balsa blocks to the base.

Weird... Stumbled across this thread whilst listening to that very album. Cosmic!

[andrebrito]

Great work !! Looks great.

[boskop]

jeep, why have you set up your matrix with 17x19 blocks? this doesn't make sense to me.

Originally Posted by http://www.freepatentsonline.com/5401921.html

Applicants have found that to form a two-dimensional primitive root array, the prime number N must be chosen so that N-1 has two coprime factors which are non-divisible into each other.

obviously your calculations are based on N = 324 (=17*19+1), which however is not a prime number.

so your block depths are actually wrong..?

[dykstraster@gmai]

Originally Posted by boskop

jeep, why have you set up your matrix with 17x19 blocks? this doesn't make sense to me.



obviously your calculations are based on N = 324 (=17*19+1), which however is not a prime number.

so your block depths are actually wrong..?

obviously

[boskop]

what?

[dykstraster@gmai]

Sorry, I didn't mean any disrespect. It's just when you put "obviously" in front of a difficult (to me anyways) equation, I think it's a bit funny.

[DeadPoet]

I'm looking at doing 13 diffusers next month or so. 144 blocks per, 82x82cm per..

Wish me luck.



Herwig

[boskop]

Originally Posted by dykstraster@gmai

Sorry, I didn't mean any disrespect. It's just when you put "obviously" in front of a difficult (to me anyways) equation, I think it's a bit funny.

ok.. well as far as i understand this paper: Two-dimensional primitive root diffusor - Patent 5401921

the number of blocks equals a chosen prime number N minus 1. The heights of the blocks are estimated as described on 7.

so N=323 blocks means jeep started with N+1 as the chosen prime number. but 324 is not prime..

[boskop]

.. as described on page 7 i meant

[boskop]

dont get me wrong, i dont mean to be picky, but ... if the block heights are not correct, this piece looses a significant part of its effectiveness. there is quite some math behind this ;)

[mattyRPG]

cn i ask..how long did it take you to make those, and roughly how much do you think it cost?

[diogo_c]

congratulations, it looks great - and i hope it sounds great as well!

looking forward to build two of these babies for me soon!