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Chronicle of room treatments to equip room with the ability to play HT at reference levels

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liverpool_for_life

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Mandate: Turn an absolutely terrible room for acoustics into one where HT can be comfortably played at reference levels, assuming capable speakers. "Comfortably" implies that the sound inside the room not induce any complaints about loudness (I understand this can be subjective, so consider myself the subject for this particular test) when HT system is played back at reference.

First step: 4 poly cylindrical diffusers on the back wall (4 ft tall, 2 ft wide and 1 ft deep). Wood, CNC cut. Mostly hollow on the inside with some absorptive material lined up against the flat end.

image1.jpegimage2.jpeg
 
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liverpool_for_life

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1000 words needed please :)
sound_cycle,

Thanks, but I'm not responsible for the design or engineering of these. I'll be sure to ask (and post) the rationale for the treatment choices once the room is done.

Subjective impressions:
-------------------------

I can't turn off ARC in my Anthem AVM 60, at my listening levels, with these installed. And reason suggests that this should be true. My room needs ARC to tame my room modes in the LF range and the highly reflective nature of my room in the MF and HF.

When I listened with the prior ARC calibration, the differences were subtle. Details that were previously being masked(that the speakers were reproducing all the while they've been in my room) now became audible. Subtle change, but nevertheless present. I could point to specific sounds in the music that I had no recollection of ever hearing.

When I reran ARC with the diffusers, bloody hell. The sound just felt much bigger, immediately. And female vocals sound more natural than before. Real or imagined differences?

Cut to Friday and it's Retro Friday (Raja songs all day) on FM 106.4 here in Chennai. I turned my AVM 60 on at 9 AM. Turned it off close to 11 PM. 14 hours. Non-stop. I can truly say that I heard the bass guitar on Raja's compositions for the first time yesterday. The weight on that sound was incredible and extremely addictive. And the female vocals? No, I wasn't imagining it.

I cannot wait for the rest of the treatments!
 

liverpool_for_life

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sound_cycle (and to anyone else that might be interested),

Here's a link to an educative (and ear-opening) video from Ethan Winer (who runs RealTraps) that helps showcase the differences in sound between a bare room, an absorptive room and a room with a couple of different types of diffusers:


Enjoy!
 

liverpool_for_life

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Mandate: Turn an absolutely terrible room for acoustics into one where HT can be comfortably played at reference levels, assuming capable speakers.
On reflection (pun intended), that's not true. My choice of speakers was definitely driven by that criteria i.e. the ability to play HT at reference in my room comfortably without distortion. Along with loud, clear and the ability to reproduce everything that was on the source. That was what I wanted for my HT. Of course, given my listening habits, I wanted really good stereo performance too. Top of the list though: A dynamic HT experience.

I live in an apartment complex on the top floor: So, HT at reference is a piece of cake :- ). First step was to address the ability to play loud without the neighbors knocking on our door, asking to be let in as well! We also wanted to insulate, as much as was practically possible, the HT from external noise as well.

I had 2 options with respect to the reworking of 1 door and 3 windows (the bare minimum we could get away with) :

a. Double glazed 5mm toughened glass with an air gap of 10mm in an UPVC frame
b. Laminated 6mm toughened glass with a 1.5mm clear poly lamination (that is an absorbent) between another 6mm toughened glass

The difference in price between laminated and double glazed was 31%, while the expected difference in effectiveness was 20%. My HT consultant felt the extra outlay wasn't justified and I went along with his assessment.

Doors and windows were installed last October (I think). No one's knocked on our doors. Yet.
 
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liverpool_for_life

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As more time elapses since the diffusers were installed, I find that the best sound to my ears is when I'm sitting in the adjacent room with the sliding door between the HT and the living room left open. It is noticeably better.

This is odd because the levels in my HT are louder(but not unpleasantly loud) than the levels in my living room, and in general, our ears perceive louder as better. Decidedly odd.
 

liverpool_for_life

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Subjective impressions after the second, smaller set of polys have been installed (haven't rerun ARC yet):
-------------------------------------------------------------------------------------------------------------------

So, my subs are actually working?! Nah, it's just that I can feel their impact now. Drums and bass guitar really showing up from the music. There were a couple of instances where, for the first time, I felt my Submersives start and stop on a dime.

Perception of depth beginning to emerge in stereo. There is not only separation of instrumental sounds, but I can now get auditory cues of where these sounds might be in space. An increasing amount of mid and high frequency details are now audible.

Vocal clarity is marginally better. I expect that treating the front wall will help to get the clarity I crave.

And, before I forget, I can now turn up the levels significantly without stuff getting uncomfortably loud. I'd say SPL levels are anywhere between 5-10 db higher than before.

I always suspected that treating my room would make a significant difference to the sound I got from my system. With the first set of treatments, those suspicions have been confirmed. Beyond any shadow of reasonable doubt.

I don't really need to see the differences in measurements between now and then to understand the effect these treatments have had. Even my untrained ears can absolutely hear it.
 

liverpool_for_life

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I'd say SPL levels are anywhere between 5-10 db higher than before.
Got a little carried away there. That was with my prior ARC calibration which was effectively voided when the additional diffusers were installed. I reran ARC and, although I can still listen at higher levels than before, the increase is most likely capped at 5 db. I'm getting a first-hand demonstration of the difference between measured SPL levels and perceived loudness. The effortlessness of the Catalysts are truly beginning to show up.

And the Submersives? Almost 2 years after I first got them, I'm getting a real taste of their famed SQ, not just their brute power.

Vocal clarity is better. Not quite at "can now turn off subtitles completely when watching Engleesh stuff", but heading in that direction.

Also, more life-like vocals. Case in point: Listening to the song "Urugudhey Marugudhey" song from the movie Veyyil yesterday night. There is a bit of dialogue from the heroine towards the end of the song and I genuinely thought the missus had returned home from going out. Scared the living daylights out of me (I jest, but only just). Then, when I realized that she hadn't, I grinned widely from ear to ear. Not because she hadn't returned (well, that too), but mostly because of how realistic my system sounded there.

I was telling my acoustician friend about the changes I now perceive. His comment: You are beginning to listen less to your system and more to your music. It's true what he says and I cannot thank him enough for that. My ears are well and truly in the process of being opened.
 

liverpool_for_life

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Oh, and one more thing: This thread has caused more than one member to contact me privately and ask for the contact of my acoustician(s). I understand why people do that too. I'd do the exact same if our positions were reversed.

I can comfortably say that when I asked they do my room, I had no idea of their pedigree. As I told someone I spoke to over the weekend: Having these folks do my room is a bit like having Sachin show up for a club cricket game. While he was still playing international cricket.

I repeated that response to my acoustician friend and he chuckled. So, please understand why I feel uncomfortable giving their contact out en masse. Many thanks for understanding!
 

newlash09

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Haha...your thread is one awesome read. I get tickled no end, whenever i read your updates. A very good exercise for my laughing bones indeed :D

Please keep this going, both for its audiophile content and amusement factor too :)

Perhaps you should try your hand at writing sir :)
 

liverpool_for_life

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Some minimal treatment on the sliding door separating the HT room and the living room. The carpet’s back in as well.

The pluck on a guitar now at high levels? Goose bump inducing, crystal clear goodness!

WhatsApp Image 2018-12-24 at 9.12.53 PM.jpegIMG_5983.JPG
 
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liverpool_for_life

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Sliding door between living room and the HT room now pretty much sealed. Makes a bigger difference for projection video than audio, IMO.

I finally got rid of my (self-imposed) mental block and moved my subs to 1/4 of the room width away from the side walls up front. Theory suggests this should be better than my previous positioning and that theory is correct! It also means that my L&R are currently on the floor, while their stands are designed and built.

Unfortunately, this has also forced me to (reluctantly) concede that I may need the help of additional subs in my room. That help will be on the way. Hopefully soon!
34254
 

Naturelover

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Good work. Slow and steady.
Along with the close-up pics, do post wide angle views to get a reference of the treatment vis-a-vis the room.
 

liverpool_for_life

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Good work. Slow and steady.
A bit too slow for my liking, if I'm being honest. My acoustics guy is a perfectionist though, so what you see in my room has gone through multiple iterations of making. Thanks for the props. I don't think I could go back to my original untreated room now.

Along with the close-up pics, do post wide angle views to get a reference of the treatment vis-a-vis the room.
Agreed. Will do!
 

liverpool_for_life

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Mandate: Turn an absolutely terrible room for acoustics into one where HT can be comfortably played at reference levels, assuming capable speakers.
(A bit of an elaboration of what I said in a private group last week)

To flesh this out in terms of tangibles, this is what I wanted:

a. The ability to play movies at reference level i.e. loud.

Why is this hard to achieve in a domestic room setting? Couple of reasons:

1. The speakers themselves can't play at those levels without distortion, thereby causing listening fatigue.
2. The room is too reflective and/ has massive LF peaks, again causing listening fatigue.

I think I've the speakers sorted out, but the room is a big hurdle.

b. The ability to watch stuff without subtitles i.e. clear.

Why did I want this? I find that subtitles distract from the visual, that's why. And, when I turn them off and can't understand what was said, I find myself being taken out of the movie/show. The Catalysts had a reputation for dialogue intelligibility, but I don't experience it in my room. Ergo, the problem most likely is in the room.

c. Clean bass with impact.

IMO, this is absolutely central to a great HT audio experience. The Submersives are certainly capable of impact, but given the realities of my room, it became clear that I really needed additional subs to get what I was truly after. The hope is that once the additional subs are in, I can get away with EQ to get the bass quality I crave.

d. Hear every bit of detail that the speakers are delivering i.e. transparency.

There's little point to speakers that are reputed to reproduce every bit of detail that's in the recording, only for the room's reflectiveness and resonances to drown them out. As my acoustician said, before the diffusers were installed, the audio was a bit of a "cacophony" in my room. Brutal, but true.

e. No fiddling with the remote, from movie start to finish.

This really ties in with (a) and (b). In effect, you want the audible frequency response in-room well balanced enough that you never have to reach for the remote during the movie watching. No need to turn it up when the levels are low and certainly no need to turn down when the really dynamic stuff hits.

So far, the installed diffusers have definitely helped with (a) and (d). Can't wait for the treatment on the ceiling and the front wall!
 
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