Hi folks,

I've spent the last few days building my panels using Ethans plans/advice and the acoustic FAQ and also based on the designs seen in another thread on these forums by dyazdani.

Although I'm almost finished the frames now, I'm aware that the fibres from the rockwool may still hang about in the air, especially as I want to make four of the panels moveable to treat another area of a recording space I have. Would it be possible to 'seal' the back of the panel in any way? Even with something like brown paper or another type of fabric? Oh and before I forget I also purchased a length of acoustic fabric so that's what's going to cover the front, sides and eventually get stapled neatly in the corners on the back made out of plywood. But of course the backs will be open and i'm not sure if there's anything I can do to seal them.

I took the time to jigsaw out the sides of the panels to reduce the amount of reflective surfaces, and make the frames as light as possible. Also my corner bass traps (2x2) will have foil facing on the front while all of the other pieces making up the depth have had their foil removed. The (2x4) reflection panels will not have foil facing.

Any thoughts, comments, suggestions welcome - and thanks again to Ethan for providing such a great forum and to everyone else for sharing their knowledge.

Cheers

Geoff

Geoff,

Very cool, nice job!

> Would it be possible to 'seal' the back of the panel in any way? <

Any soft fabric will do for that.

> I also purchased a length of acoustic fabric so that's what's going to cover the front, sides and eventually get stapled neatly in the corners on the back made out of plywood. <

If these are to be used as bass traps mounted across corners or off the wall, do not put a plywood back on them! Just wrap the fabric all the way around and staple it to the wood edges.

--Ethan

Nice Job! Scary someone actually used my project as a model...

I would have liked to cut holes in the sides as well, but laziness set in.

Hi folks,

Just thought I'd share the on-going construction pics of my new panels. I know when I was looking to make my own, the more pictures I could find the better I got to know what all my options were. That is not to say that these panels are in any way the best way of doing things, just that this seems to have worked for me so far and may help a few other folks out.

Ethan - I'm just about there getting all the panels finished, but I'd like to ask your opinion on hanging them. The side reflection panels (2x4 with one peice of 2" thick rockwool) I think I'm supposed to hang away from the wall, leaving if possible the same space as the depth of the panel itself. I've got a few ideas on how to do this, but I'm not sure if they'll be a bit 'Heath Robinson' and I would be very grateful for any advice.

Also, my bass traps (2x2's for the corners and one 2x4 to go at an angle at the top-back wall where the back wall meets the ceiling) I was going to put a couple of hooks into a joist and use picture frame wire or even light-weight chains to hang them from. I'm sure this is possible with my build of flat/apartment as I have a clothes pully in my kitchen and this is tethered to the ceiling in a similar fashion. It's so strong I could probably swing on it - but rest assured I have never tried and probably never will!!

Anyway, here are some more pictures of my work in progress.



2x2 Top corner bass trap finished.



Frames showing extra support for rockwool slabs. I had to do this as they turned out slightly smaller than I'd allowed for so I had to add a wee bit of wood around the sides to keep it in place and also to support it and stop it from sagging. That's the frames on the right-hand side. in the above picture.



Three 2x4 reflection point panels and the two top corner bass traps ready to be mounted.



Here's a 2x4 reflection point panel finished with the fabric stapled on. Basically, it was a case of laying it flat and not moving it until it was stapled all the way around. I figured if I moved it, I'd create a crease or a fold and then would staple the rest of the screen with the fold in place. That way, I managed to get the fabric looking even.



This last picture shows the corner up close. Just lots of patience, and *lots* of staples!!

All the best

Geoff

nice job!! how did you fold the fabric around the corners? it looks great in the close-up!

> nice job!! how did you fold the fabric around the corners? it looks great in the close-up! <

Thanks!!

It's just a case of taking it really slowly and stapling every time you get the next bit taught. The fabric is actually in two bits.

It's like wrapping a big present, there's a bit of a fold underneath each corner, then when I've got that done I cut a straight line from the remaining fabric and then started stapling again.

When I get the next few panels covered I'll try to take a few pictures as I go. That might explain my method a bit better.

Cheers

Geoff

2 thumbs up sir.. OUTSTANDING!!

Geoff,

I'm not much of a construction guy, and however you can get them to stay in place will be fine.

--Ethan

I'm SO copying this...

This is so beautiful, I've got tears in my eyes.

Hi Geoff,
God work, I see you also "opened" the sides of the panles, as I did (using a milling machine):
http://www.musicplayer.com/cgi-bin/ultimatebb.cgi?/ubb/get_topic/f/26/t/001440.html

I also see, you are a step further as I am, you have covered the panels with fabric. Any acoutical results?

trif.

Hi Trif,

To be honest, it's just finger in the air stuff over here. From reading the various posts I'm pretty sure most of the stuff I'm doing is correct in terms of deadening the room and reducing standing waves / early reflections but I am a complete idiot when it comes to anything remotely mathematical.

I started down the road of trying to understand acoustic measurement, but soon got lost in the mire. I realise it's a hell of a lot of effort for something that's finger in the air, but I generally go on if something sounds right - especially while mixing, rather than the exacting art of knowing which frequency to cut and which to boost.

So no waterfall graphs or acoustic measurements I'm afraid.

I opened the sides of my panels with a jigsaw before I put them together and it was incredibly time consuming given the amount of frames I made (11 in total). What is a milling machine? Your frames look great.

I'm also at a bit of a lull just now with my frames as I underestimated the amount of fabric I would require and having ordered some more, I'm two weeks down the line and there's still no sign of the stuff.

I also saw that you have your speakers on high density foam pads. I'm thinking of doing the same for mine, although I don't really know which ones to get - to be honest they're quite expensive for what they are as far as I can see.

Cheers

Geoff

Geoff,

I think your efforts will be rewarded well with a more balanced, acoustically sound room. The panels look great and you have done a very good job of illustrating for some of the DIY folks just how it can be done.

This thread is of great value to others.

Nice work!


Joel

Geoff,
Milling is the process of cutting away material by feeding a workpiece past a rotating multiple tooth cutter. Just type in your browser "milling machine" and you will get plenty of result. In my case milling machine was used to cut out all the circles on the side of the frames. Huge amount of job!!!

Now, looking at your frames, the jigsaw is very much DIY type of solution and I believe you that it also requires plenty of time. But well done.

In my case Bryan was the MAN, who conducted all the acoutic measurments, including speaker-sitting-panels-soffits-placements. Do not forget this is all important! Bryan has answered all of my quistions. And the result is just fantastic. I have 16 panels, and appr. 16 m soffit in my room. My response swing is around 7-8dB.
Funnily enough, in the same room I have one boombox, what after the treatment just started to "produce" more basses.

BTW/OT, I have just finished my DIY grot-box project, and it can be found on:
http://www.soundonsound.com/forum/showfl...&fpart=1#250472
I did not measure its response yet, but I am very curious.

Back to your question: the foam under my Dynaudio speakers is from Auralex. If it is the best foam/approach I do not know. Next: the stands under the speakers are filled with dry sand.

In fact I had an extensive very original design to make the frames from metal, but I did go for the MDF solution.

This forum is very helpfull as are all the guys here.

trif.

I finally got all my panels finished after two weeks of waiting on more fabric coming in. I've placed the panels round the room with the exception of the top, back corner 2x2 bass traps which I've managed to balance on top of the door and the other on top of a shelf. The difference in the room of course is incredible. Even when you speak while moving through the house and you go into the treated room your voice all of a sudden becomes as clear as a bell.

Songs I know really well I've been playing through the speakers in the room and I'm hearing things I didn't know were there.

Also, although i'm not much a techie in terms of measuring responses etc I can totally hear certain notes or frequencies being picked out. I'm guessing without the bass trapping totally in place yet there are some flyaway notes and tones happening, but they're so more apparent now that the room is treated. I think I still need something for the ceiling and the sides above the reflection panels. I'll post pics once I get them up on the walls.

I know I've asked this before, but I still have few ideas on how to effectively hang the wall reflectors. If anyone who has done this before is reading this and can put any ideas my way I'd be very grateful.

Cheers

Geoff

Geoff,

> The difference in the room of course is incredible. <

Yep.



--Ethan

Another believer.

I believe! I believe!

Listening to Aimee Mann's Lost in Space, track 1 - Humpty Dumpty. That drum fill at the beginning and those mellotron strings (chamberlain cellos I think) when they come in at the end of the first chorus. Acoustic nirvana.

Just one question - a ceiling cloud made out of the same rigid fibreglass/rockwool...Foil on or off?

Cheers

Geoff

Geoff,

> a ceiling cloud made out of the same rigid fibreglass/rockwool...Foil on or off? <

Off, unless it's intended for bass trapping and it's not at a first reflection point or over a reflective floor.

--Ethan

Hello again folks. Getting to the end of the project now! All the panels are up and I've also constructed a ceiling cloud out of two pieces of rockwool using much thinner wood for the sides.

Pics!!



This is the method I decided to use to fix the panels to the wall. a bar across the back of the panel rests on three 'fingers' coming out of a wooden plate fixed to the wall.



I then added a thin bar to the front to stop the frame from falling off once it was attached.



A thin spacer was then fixed to the bottom of each panel to hold it away from the wall.



Finally, a scrap of wood was put into place on the 'fingers' to stop the panel from being pushed in by accident. All in all, a bit heath robinson but it does the job.



Also a wee bit of measuring got them evenly spaced horizontally and vertically - even if the walls in my flat are squint in the first place!

The corner one took a bit more thought, but with a little bit of help I managed to work out the best spacing and built a support with the shelf idea again with a bar across the back of the panel.



Here's the panel on the shelf. I had to cut the bar support to allow it to fit flush against the wall.



It looks like it's being magically held in place when seen from the front!

(post continues below - 8 images per post)

Moving on, the corner bass traps (2'x2') needed to go into the top, rear corners of the room. I tried going into the ceiling for this, then soon realised that unless I hit a beam I'd be going into plaster and thin wooden slats. They would hold but I wouldn't get the angle I required. So I had a quick look at the way Ethan uses to suspend Real Traps and saw that the wall would be a much safer bet. I fixed a plate to the wall with four long screws into plugs. Finishing by putting a large eye hook into a further plug in the middle. I ended up not using the large eye hook and just used smaller brass open hooks screwed directly into the wood, which seemed just as good. The wood plate won't budge from the wall in a hurry as it's on tight and I used the same open hooks on the back of the bass trap itself. It attaches to the wall plate in four places by lightweight chains, which have a load up to 20kg each. The bass trap itself is only 5kg and is divided over three taught chains, the fourth is there just for good measure.





The middle bass trap (2' x 4') is held up with a block on the wall and is resting against the two corner traps. The angle is not ideal, but I reckon it's probably ok.





The ceiling cloud I made out of two pieces of 2x4 rockwool, building a much lighter frame and covering with scraps of the acoustic fabric. Because they were scraps I didn't get them quite as taught as the other panels and had to 'join' them in the middle with another piece of very thin hardboard, which also doubles as a support for the rockwool so it doesn't sag over time.



Again these were suspended with chains and hooks, although the weight wasn't so bad so the hooks going into thin wood slats was fine for this. Angled slightly up at the back and down at the front. I don't know if this makes a difference, but it seemed to make sense.

Finally, I don't have a wide-angled camera and as such it's quite difficult to take a shot of the whole room so I took a few shots from behind the desk to give an idea of the overall room.





The curtains on the front wall, I realise don't make up for the fact that there's a solid wall on one side and a window recess on the other, but it evens up the room and keeps the light out - one thing I hate is squinting against a bright light in the background when i'm trying to look at a screen. Although I did line the ones on the side of the window to make them slightly thicker.

Anyway, onto how it sounds. In a word - incredible. The detail on vocals and strings, guitars, percussion etc is just fanatastic. I keep finding songs I haven't listened to for years and when I play them I hear them for the first time again.

However - and there's always a however, through treating the room acoustically I have found a frequency or note that seems to ring. I'm not very up on the whole hertz and measurements etc but I fear I might need to get into that now. Every time an Ab (A flat) bass note appears in a song the bass booms. I'm guessing this is the resonant frequency of the room. Any note either side seems fine and the bass overall is punchy and tighter than it was.

My guess is that the bass trapping at the top and back of the room is good, but not deep enough. Perhaps the room is too small to angle the corner traps in and they should perhaps be flush with the side walls. By this I mean, perhaps the bass is getting in the corners and repeating back out again. The one between the 2x2s is perhaps not at the right angle and all three may need to have the space filled behind them.

In addition, I think perhaps the speakers are too close to the corners, albeit one side is onto a window which is less of a problem. I could bring the whole desk etc forward but I'd lose some space. I also wouldn't want the hassle of taking down the side reflection panels and re positioning them, although there is some give and take left and right of +/- 5 or 6 inches.

Any thoughts, comments, suggestions more than welcome. I've come this far and would like to get the room sounding as good as possible before I finish.

Cheers

Geoff

Geoff,

Looking good!

> I'm not very up on the whole hertz and measurements ... I've come this far and would like to get the room sounding as good as possible before I finish. <

I think it's time to do some measuring. I mean, how much is your time and aggravation worth? You've saved so much on the treatment by going DIY, I suggest you spring for the relatively little $150 to get ETF. Once you get it going, each measurement takes five seconds. And from that you'll know the true response, modal ringing, and so forth.

--Ethan

ETF purchased. I may be some time....



Geoff

Hi Ethan,

I'm afraid I can't make head nor tail of the software (R+D) which is not a slight on the software itself - it's excellent and I'm sure has proved its worth many times over. I'm just don't have a technical mind and as such can't really make sense of the output.

However, I am attempting to place my speakers to get rid of the bass frequency problem and to this end I have taken everything out of my studio leaving my speakers, my DAW etc and a seat and I'm placing a speaker, moving round the room to see if it changes and I'm getting there. The booming frequency went as soon as I moved my head further back. I tried moving everything back and forward but soon got all the leads in a mess so thought, I'll get the speakers right first then move everything else back in.

I think the corners of my room (behind the speakers) are the cause of my problems. Putting a signal to one speaker only and moving about the room I get the strongest bass signal when I am on the opposite wall about a foot in front of the line of the speaker. Not the best listening position I think you'll agree and then when I put the other speaker on in the same position I lose most of the bass altogether.

In fact, the best overall listening position with the strongest, fullest consistent bass is about 1 foot off the floor in the about two feet back from the line of the speakers!! So all the bass is going into the floor it seems.

Sorry if this is a bit of a long winded explanation. I feel like i'm struggling a bit now.

Thanks again for all your help so far.

Kind regards

Geoff

Update on the update!

The table I have in front of the speakers is causing major problems with the bass, especially the Ab. So it may be that I have a large reflective surface *in front* of the speakers which is pretty bad all round really...

Geoff

Geoff,

> which is not a slight on the software itself <

The user interface is not as good as it could be, but it's not too bad either once you know what to do and have done it a few times. First, do you have the mike and wires connected properly? The image below is from the ETF Help file, and I added the part showing the "Y" splitter which is also needed.

> I'll get the speakers right first then move everything else back in. <

Yes, that's the best approach. Are you able to get a basic low frequency response? Once you can do that the next step could be running ETF in "continuous" mode. This sweeps repeatedly and updates the screen repeatedly, so you can move things around in the room and immediately see what changes.

--Ethan

Since you guys are moving on this subject, I too just purchased the EFT which is of course now RPlusD. My simple question is how to place the microphone? I am using for now the RS SPL meter mic. Ethan I noticed in one of your photos that you had the mic facing the floor. What's that all about? I have run some preliminary tests and have some results, but I wasn't clear on the mic placement. There is a section on EFt's site called "demo Room", but it has very little to do with a studio, it more geared towards a nice listening room, moving the speakers and listener around for optimum sound.

Geoff,

BTW did you end up with EFT or RPlusD?

How about you Ethan what's up with the new name?

I noticed Doug Plumb is offering to supply EFT if you want it, but I am following his urgings (can that word be plural?) and just loaded the RPlusD.

Hi Ethan,

"Are you able to get a basic low frequency response?"

My initial loopback response test was very similar to what Doug had on the screen and then I hooked up an SM58 through my MindPrint mic pre and managed to do all 32 measurements and save them as an overall room measurement. I then went on to save them and followed the next part of the video to do a low frequency response (I think that's what it was), performed another 32 measurements and saved this to a file.

I'm watching the videos where Doug goes on to explain what to do with the measurements, but I think through the use of terminology I quickly lose the thread and I can't figure out what's going on. At that point, my measurement file just looks like 32 nicely coloured waves on a graph and that's about as far as I get.

I'm going to make a real effort over the next couple of days to get into the software and exhaust all the help material to see if I can break through my cloud of ignorance!

Anyman - to answer your question, I went with R+D after purchasing ETF on Doug's advice.

Cheers

Geoff

Geoff,

Have you looked at both the "impulse response" and the "frequency response". The sound that plays through your speaker is a very specialized sweeping PSD wave form. When you switch your view to a bode respose you can see the room in db vs Frequency. It is there that you will see the modal responses (dips and peaks) caused by your room. From there you can switch to a waterfall graph to see the decay of the bands and relate to the delay or time propagation of the frequencies.