Haha, will do 
I doubt she’ll do the painting until the new year when she’ll have more time.
I’m looking forward to seeing what difference they do make … hopefully a positive one! 
Cheers,
Mark
Have you got the Roger Waters “Us and Them” Blu-ray to play on that projector?
I was fortunate enough to be able to build my own room from scratch (with the help of an architect buddy who is also an audiophile). For those in a position to do so, I heartily recommend it as the most significant upgrade you can make.
Basics of the room. 1) Minimum of absorption, focus on refraction/reflection. Angled panels behind speakers and on listening wall to bounce High and mid frequencies up to the ceiling and eventually trapped in hanging acoustic panels 2) built in bass trap/ Helmhotz resonators in front corners behind speakers. 3)Vaulting ceiling rising 2 floors behind the listening position. That gives 2 planes out of 3 non parallel. Side walls are parallel but on the first reflection point are the shelves that house the record collection (approx 6000 albums do their own reflecting/refracting and absorbtion). 4) dedicated power circuit
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A self-appointed expert in YouTube terms would be someone with few followers.
Darko has 214,000 followers.
Many of them see him as an expert, and he does have expertise and wide experience to share with them.
He has reviewed hundreds of pieces of hifi gear for over a decade.
If you want to critique him why not attack his weaknesses eg he listens mainly to synth music, he doesn’t use or fully understand measurement of speakers and other hifi gear.
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I couldn’t agree more 
Enjoy Peter
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Hello Mike, I don’t, was a bit grumpy with Roger when I was young, but I’m over it now!
I do have Pulse, Delicate Sound of Thunder and Remember that Night which I watch quite a lot on there 
DSoT is in DTS and sounds incredible. RtN has Bowie on Arnold Layne and Comfortably Numb (fantastic!) in the Royal Albert Hall and is very atmospheric… a great concert if you like Floyd/Gilmour.
The combination of surround sound and a large screen is something I’d find hard to be without. The SN3 has given a big boost to the AV side too.
Cheers,
Mark
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Thanks @JohnC2 
Unfortunately, the information is spread all over it.
I won’t use canvas, even less painted canvas. Painted canvas would be counterproductive as it doesn’t let air flow through.
I’d use acoustically transparent fabric.
The one thing we need when treating a room is predictability.
Owen Corning provides helpful information about their products, for instance, the sound absorption coefficients.
There is a lot of information spread around the web and not consistently accurate and/or correct.
Denser materiel is not always better. It depends on the amount and your goals.
As illustrated below (for a thickness of 30cm)
If your goal is to absorb “bass” only (below 100Hz), than porous absorbers like fiberglass, rockwool, etc. is far from being the best choice.
My goal is to absorb everything from 65-70Hz up to 20kHz.
For the 35Hz-70Hz range, I’ll add tunable diaphragmatic bass traps.
I’d like to achieve an even decay time down to 50Hz.
ADDITAMENTUM:
Regarding the choice of porous material, I’ll probably go for Caruso Iso Bond.
I put the foam in the frames today and spent some time doing measurements in REW (UMIK-1 on a tripod). I wanted to see if they made a difference and to see how the room has changed since I last measured it almost a year ago.
This shows the empty frames, then with the foam added and finally with the canvases added on top.
As expected not a huge difference, and is best without the canvases … but only a decibel or so.
The waterfall graphs show a small improvement and are smoother.
I also used REW to try and find a better position for the speakers, ended up with this for now … port bungs reduced the bass effectively. One bass peak has been reduced quite a bit and the high frequency falloff has improved.
Initial listening tests … too early to really tell, but from what I’ve heard so far it seems faster and tighter, the 20 minute opening track on 2112 was probably the best I’ve heard it here, the drumming and Geddy’s vocals on that are a good test
Will listen for a few days and see if I continue to like it.
One last thing I tried while I had everything setup was to cover the TV between the speakers with the foam. It’s something I keep reading is a big no-no but I was pleased to see that it doesn’t appear to be in my room.
Cheers,
Mark
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A misconception widely spread
I parsed the thread and realized there was a misconception widely spread.
Many believe that room treatment is used to adapt the audio system to the room.
In other words, the bigger the system, the more we have to treat the room. Conversely, a smaller system prevents from needing room treatment.
Acoustic treatment isn’t a way to adapt a system to its room.
Acoustic treatment aims to correct the room’s frequency response. That’s all.
In other words, it prevents the room to mess with your system’s sound (to a certain point), whatever the system.
Every room has acoustic problems. As long as there are walls, there are acoustic problems. Unfortunately, it is that simple.
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More experimentation today, learnt a lot about my speakers … they’re very forgiving in positioning, especially with distance to the wall, and toe-in makes little difference. Fitting all four port bungs reduces low bass peaks significantly in my room without affecting higher frequencies.
They are now wider apart, not as far as I had them before I moved them yesterday, and have no toe-in.
I also experimented with the listening position, moving 11 cm forward from the rear wall helped a lot with the midrange.
New measurements, these were done at 74 dB, where the horizontal line is in the graphs.
I averaged 3 positions around the listening position.
First with 1/6 smoothing:
With Physchoacoustic smoothing (how our brains interpret the frequencies apparently)
Waterfall still looks ok, apart from the low end.
With the sofa a bit further from the wall I might be able to squeeze a couple of monster bass traps behind it …
Will see what it actually sounds like tomorrow.
Cheers,
Mark
Hello Thomas, I see this being about making adjustments to certain areas of the room acoustics so the system we have works better in it?
Or have I misinterpreted what you’re saying?
These past couple of days I’ve been thinking that maybe I should consider smaller speakers that don’t go so deep. Then maybe I wouldn’t need bass traps as the room modes wouldn’t be ‘excited’ as much.
Regardless, I find this whole topic very interesting, and part of me is wishing for a dedicated room so I could experiment and learn more with the freedom that would give.
In my case it’s very much “The Living Room Reality”
Cheers,
Mark
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It also looks as though there is something (such as a piece of furniture perhaps) in the room causing a secondary resonance (possibly mechanical) at around 160Hz.
I tend to view it as a three component interacting system, the speakers, the room and the position of the listener. Of the three this is most frequently the general situation:
At the low frequencies, the interaction of the room and the LF output of the speakers often has the greatest effect.
At upper bass frequencies, the interaction of the room and position of the speakers often has the greatest effect.
At mid frequencies, room reflections with the position and ‘character’ of the speakers often has the greatest effect.
At high frequencies it’s mostly determined by the speakers and their position (i.e toe-in)
Note that at LF this is more complicated when considering ported speakers (reflex, open transmission line or ABR, the same issue applies to all). At port resonance the output from the port is phase coherent with the output from the front of the speaker, but delayed by 1 period (i.e. a 360° phase delay); at all frequencies other than the port resonance the output from the port is phase non-coherent.
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I see it a little differently.
The room being a constant and the audio system and the listener are variables whose respective positions may vary.
To accept the room as part of the reproduction system is, in my opinion, to accept that the room interacts with the reproduced music.
I hardly accept that idea.
I tend to see the room as a problem and not as part of the reproduction system.
I really quite appreciate my room when listening to music. It provides me with shelter from the elements, keeps noise away from the neighbours, gives me somewhere to put my couch and also gives me more bass. It is certainly a vital part of my system.
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The speakers (and electronics for that matter) are just as constant as the room, in fact there are usually more ways* in which you can alter the characteristics of the room than there are ways in which you can alter any given pair of speakers. If you consider using different speakers, then the extent of difference* at low to mid frequencies is similar for use of different speakers in the same room or the same speakers in a completely different room.
While neither the speakers nor the room directly interact with the reproduced music itself, both interact with the air pressure signal that conveys the music, and hence both interact with our perception of the music.
.
.* Perhaps the best measure of ‘number of ways’ & ‘extent of difference’ may be the engineering / mathematical concept of ‘degrees of freedom’.
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Yes that’s strange, wasn’t there in the first round of measurements… can’t really think what it could be. There’s a solid wooden cabinet on the back wall opposite the right speaker and a metal frame bookcase in the front right corner, neither of which have moved.
It was a fun experiment, the foam behind the canvases has made a small but worthwhile improvement for little cost.
Positioning the speakers and listening position using measurements instead of by ear has made the biggest difference of course, time will tell whether they stay where they are. Certainly sounding nice at the moment.
I’ll do some more in the new year once the giant diffuser has been packed away
Cheers,
Mark
On the earlier waterfall plots there is a similar effect at around 120Hz, could this change be a clue to the origin?
(120Hz corresponds to a cavity distance of 1.4m & 160 Hz a cavity distance of 1.1m.)