Very nice @bunter !
I guess you’ll place these at the first reflection points.
If you can do so, add some thicker absorbers that will allow you to treat lower frequencies.
With foam, you will only hit the upper mids and highs.
To treat down to 150Hz with porous material (foam is porous, btw), you need something with a density of 40-45 Kg per m3 and a thickness of at least 17cm.
Enjoy the upgrade.
Room treatment is in my top 2 upgrades, and buy a vast margin the less expensive.
Looks really cool bunter, well done! They could also be good behind your head on the back wall 
ATB Peter
yes, I’m placing mostly on the back wall behind our sofa. The speakers are on the long wall, so the side reflection points are further away than the wall behind me.
The Magico S3 MkII left yesterday 
The Magico M2 should arrive in 1 or 2 months 
The Taiko Extreme should arrive around the same time.
And the Nordost Valhalla 2 cable a tad earlier.
For a few weeks, I find myself without music but with more space to tinker.
My goal is to add some 40 cm thick BassTraps and to build a room partition in acoustic material.
The 38 m2 space will be divided in two, but without being really separated. Acoustically speaking, for any frequency below 120 Hz the room remains 38 m2, which is good. 
I’m pretty proud of my listening room
I know my room has good acoustics. It is objectively good (measurements) and subjectively good as well (I like it).
But I have never compared it to other people’s rooms. I’ve only compared it to my dealer’s listening room, which sounds a lot worse.
The people who came in to buy the Naim gear and Magico speakers (the guy who bought my Magico had a pair of PMCs before) were all totally stunned by what he heard in my room.
It was funny, when I turned off the music, they didn’t speak. They would only say quietly; this is beautiful 
Hi Thomas
Excited for you! Been following your journey and
though you have absconded from Naim elsewhere (lol),
it’s nice to have alternative, neutral and experienced
voices here on the Forum to share and enlighten all
sonic matters in good light. It helps you are an
experienced 500 series owner.
Your fixation with treating your room is a good “priority
reminder” for all of us music lovers. It’s been nagging at me
to delve a little deeper to understand just the basics.
Taiko is serious stuff. Which Dac…?
Another thought as I read your post, gentle share
from my painful experience - unless treated by a trained
and experienced acoustician, I wouldn’t do any “fixed position”
acoustic treatment till the speakers arrive. Safer to use anything
that offers the flexibility to add and remove at will.
Monsieur French Rooster shared good feedback in the other thread
to room-treat lightly [and gradually], so we don’t over-damp or
deaden the sound. Any treatment fixtures are a double edged
sword. I like anything easily “undoable” for room treatment.
When your lovely new speakers have arrived and are running in,
it’s where the fun and exploration begin… since we’d be able to really
tell what room nodes need to be treated as you play with volumes.
I found my “final treatments” best when the system was run in.
If we have treatment materials pre-fixed, it’s a chore and nightmare
to remove if they do not work as intended. I was stuck with some
wall material which in hindsight did little for the SQ, because I had
prefixed this prior my system’s arrival. Not a good idea in hindsight.
Trained acousticians - the good ones - come understandably with a
cost but it’s probably some of the best money to spend if outright SQ was
a priority. I loved DIY and still do, but it only brought me to a certain point
and some money just has to be discerningly spent to get things “right”.
It’s a risk of course because hiring someone trained doesn’t mean zilch
if he doesn’t do a great job and is out to maximise expenditure
without salient results.
Now that I am restarting from scratch, I prefer to undertreat
a room first, and then gradually work my way to addressing
any nagging issues as the system beds in. It’s never “a one time fix
and it’s done” scenario.
Take your time and there’s not rush into room treatment since your
speakers aren’t in. The last I saw your listening room it was already
quite treated! Beautiful room you have. Every speaker brings different
nodes to the room. I made the mistake of putting the horse before
the cart, as I was so eager, not that you are in any manner as I know
you’re detailed and very careful - you should be with the outlay so far.
Hope this helps some and have fun with the process.
Wish you audio bliss.
Hello Phil,
Thanks for your message ! 
My DAC is the Soulution 760.
I have added the details of my system to my profile.
The nice thing about acoustics is its predictability. It’s a mechanical problem like any other.
Although my practical experience is limited to my room, I learned a few things about acoustics and psychoacoustics during the past 3 years. It’s a facinating subject. It’s kind of my hobby.
We don’t need to have the speakers in the room to know what their frequency response will be. All we need is their frequency response at a specific SPL and their approximative position in the room. The treatment is then added accordingly, with in mind the goals we want to achieve and the budget.
With all due respect to FR, the terms over-absorbing or deadening don’t mean much.
It is clear that adding acoustic treatment without really knowing what we are doing can lead to an unpleasant imbalance.
The trap of DIY is, as you know, adding foam panels, curtains, etc. and expecting miracles.
The reality is that too much of those invariably leads to an uneven decay time.
Comb filtering issues and decay time are critical!
These are the two things we’re after when treating the room.
The first will bring “intelligibility” and reduce listening fatigue. The second allows reducing the impact of the room evenly: more speakers, less room.
But… achieving an even decay time down to, let’s say, 60Hz is quite a challenge. Not in terms of complexity; that’s relatively easy when we understand the basics. It’s the amount of treatment needed that is the problem. It’s enormous!
An uneven decay time or, said differently, a room treated for high frequencies will lead to a so-called “dead room”. It’s like adding a high pass filter to your speakers, attenuating the upper frequencies. Not nice.
What I’m going to add is just a complement to what I already have. It won’t do miracles.
But my goal is not just about acoustics. I really want to split this space in two.
→ The Listening Room Reality - #879 by Thomas
Of course, my room isn’t perfect in terms of frequency response. It can always be better, especially regarding frequencies under 100Hz.
But for that, I plan to buy some fairy powder : PSI AVAA C20 
EDIT : I’ll take some pictures when the speakers arrive!
Hi Thomas, been reading your news bulletin with great interest. Tell me, did you try to fire your speakers down the long way in the end, ie front wall to the left of your present listening position ( you know the one with the scary cheese man monster behind the curtain 
). Best Peter
Hi Peter,
The initial “acoustic project” should cost 30K.
With the purchase of the Magico M2’s, the Taiko Extreme, the Nordost Valhalla2 cables and the audio rack, which alone will cost 10k, I have blown the budget!
So I’m going to leave things as they are. The separation will be made up of items that I can reuse. I’ll make some measurements then, if needed, add a couple of AVAAs.
The big changes below will be made in 2023.
I just knew somehow… Thomas… knowing your fastidiousness with set-up, when the time comes… I could cajole you over for a look and listen…
…
Ok… Many ways of skinning the hi fi cat…
I like diffusers in the right areas. With absorbers to boot. But too much of a good thing, aint, and FR understood this very clearer from the way he wrote so succinctly and clearly in his summary on the other thread.
Right… I’ll read up some on comb filtering and decay time - technical. Not clear otherwise. Goosebump territory for the speakers to disappear in a carefully-controlled room.
You meant to say bass control, to say 60hz, would require crazy amounts of room treatment. We tame the bass nodes in the room with bass traps attenuated at the certain range - some higher, others less, issue is how much to apply and with what equipment - so it gets really technical and mind boggling for most including me. But there is no excuse in not knowing, so we need to spend time learning more to understand, but I think it is quickest to leverage expertise, never blindly.
This is where the life gets sucked out from the sonics, one of my worst fears of over-doing things.
WRYB - whatever rocks your boat.
Interesting fairy powder… it never ends.
We’re waiting to see your new babies!
Wish you an excellent set up, Thomas.
Lovely room as I recall. I admire the serious effort which is no joke. Thank you Thomas for sharing.
I love some of the posts here from the Forum - and in return will support it with a healthy mutually beneficial exchange of constructive ideas. It’s how we all learn together.
But Thomas, why not just allow unwanted low frequency to loose itself in that long (deep) space- no back wall reflections for mids/highs coming back to your golden ears either? 
ATB Peter
That’s exactly what’s planned
as shown below :
EDIT :
It is not a wall behind the listening position. It’s a gigantic BassTrap (with a door). A very light 45 cm structure will support all the absorbing material.
This wall will absorb 100% of all frequencies down to 500Hz. At 60Hz I’ll still have 70% absorbtion. After that it will go down to a decrescendo.
Frequencies below 60Hz will pass through the wall, partially absorbed, and then lost in the back of the room.
Okay Thomas, I did see and understand your plan but now with today’s events and having had 2 glasses of red, I shall comment no further 
( in fact not much different situation from last time I deleted my post) 
Do allow me to ask, WHY the constructed wall behind you purely from a acoustical point of view?
Have you ever watched the film Fargo, where the guy says to the detective ( whilst The World is falling out of his bottom ) ; “ I’m cooperating here” Best Peter
The “wall” behind, isn’t a wall. Just a gigantic a absorber. As explained above. The “Edit” 
Why not a real wall? A real wall, reflecting upper lows and above, will only worsen things.
I don’t want to have a smaller room.
From an acoustic perspective, the room will remain 38m2, with all the advantages of such a volume.
…but you will be sat in a cell like structure! Why simply not try without the absorption structure to start with? ( I bet you won’t audibly need it). In this way you won’t isolate yourself from the rest of the living space and the rest of your family? Just say if I’m becoming a pain in the arse, I’ve had worse…. 
Yours humble Peter
lol
My sentiments too but I guess he’s trying to demarcate the space for different purposes.
There is no such thing as too much BassTraps
This channel explains things in a simple and straightfoward way.
→ https://www.youtube.com/c/AcousticsInsider
If you wish to learn more, the following is a must have/read :
Absolutely. Controlled environment is the key word. More speakers, less room in controlled way.
It’s not that complicated. The only thing we need to know is that low end is really really really hard to tame (You hear your neighbours Subwoofers, not the tweeter ).
The other thing to understand is that absorbing too much of the upper part of the spectrum leads to imbalance. Like throwing a blanket over your tweeter and mid driver. Sound gets dull, darkish… dead. That’s exactly what FR did or experienced: a couple of foam panels.
This is not room treatment
Yes and no. Placing foam, which does nothing for low frequencies, at your first reflections won’t “suck life” out of the music. It’ll reveal how good your speakers actually are. Whatever their price.
Of course, distortion is something we can easily accustom to. Each to their own, after all.
Unfortunately
Mee too!
In the meantime I’ll add the “acoustic wall” and have 3 dedicated main lines installed. With GigaWatt circuite breakers and cables.
GigaWatt G-16A 2P
and GigaWatt inwall power cables
In-Wall Cable GigaWatt LC-Y EVO 3X4
Or perhaps Oyaide (but they could be a bit to stiff to fit my inwall tubes)
That’s exactly it. In a cell like a monk! 
I’ll be surrounded by three walls covered in BassTraps. I will add some very simple diffusers, a bit like the ones in the new Naim listening room.
The front wall, between the speakers, will have the diffusers I currently use.
I will add enough diffusion to make the listening room pleasant. For example, I would not cover the floor with carpet, except for a rug at the first point of reflection.
Adding carpet is, in my opinion, a bad thing to do. Our brain needs to have reflections from the floor.
Your never are Peter!
I like to take things with a sense of humour, and never too seriously.
I do things with passion, but never take them too seriously.
And let’s face it, even though I spend a fortune on HiFi I could sell it all tomorrow without a second thought.
The only thing I would find hard to live without is my little family and sport (climbing, alpinism, etc.)
