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

[ONEMANARMY]

I am a big believer in room acoustics and therefore interested to know what you have done to address the LF issues.
In my experience the highs & lows are much easier to resolve than the bass.
I've used high density rockwool, cut into triangles and stacked in corners from floor to ceilings in my previous setups.
This had the most profound effect in my room. Once the bass was cleaned up, the highs and mids sounded clearer.

(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!

 

[raptor77]

A bit too slow for my liking, if I'm being honest.

You have no idea how much we're all enjoying this slow and steady buildup to audio perfection in your room!

Its the same story I would guess for most of us: spend increasing amounts of money (and get increasingly dirty looks from our better halves) to get louder and cleaner sound in the hope of matching something we heard in a reference room. It just doesn't work in apartments until you do what you are doing. I get this feeling now that I should stop upgrading components and think about the 2 large windows, gleaming tiled floor and 4 doors that are all part of my living room....

Bravo!

 

[elangoas]

I've used high density rockwool, cut into triangles and stacked in corners from floor to ceilings in my previous setups.

What density did you use?..

 

[ONEMANARMY]

100kg/m3

What density did you use?..

 

[skdas]

Sill confused regarding density for bass trap, what works best near around 45 kg/m3 or 100 kg/m3 ?

 

[elangoas]

Sill confused regarding density for bass trap, what works best near around 45 kg/m3 or 100 kg/m3 ?

A lower density material, which has higher Air flow resistivity (least number) should be good for a trap.. So 45 kg/m3 would be best.. Loose rockwool should also be good, as the density should be lower than 45 Kg/m3.. Meaning it is not compressed..

Below is an example of rockwool products, sourced from the net..

 

[liverpool_for_life]

Entire ceiling (or) a portion of ceiling?..

Only a portion. My acoustician cares more about the fact that this isn't a truly dedicated HT room than I do :- ).

 

[liverpool_for_life]

I am a big believer in room acoustics

That makes two of us!

and therefore interested to know what you have done to address the LF issues.

From my earlier post:

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. (emphasis added)

My acoustician has mentioned the possibility of adding some treatment in the corners to help with the bass, but that's going to only come after the front wall has been completely treated.

I've used high density rockwool, cut into triangles and stacked in corners from floor to ceilings in my previous setups.
This had the most profound effect in my room. Once the bass was cleaned up, the highs and mids sounded clearer.

Sounds good. Were you using EQ prior to passive room treatment? If so, how would you compare passive room treatment with using EQ alone?

 

[liverpool_for_life]

You have no idea how much we're all enjoying this slow and steady buildup to audio perfection in your room!

Well, at least someone's amused ;-)

I get this feeling now that I should stop upgrading components and think about the 2 large windows, gleaming tiled floor and 4 doors that are all part of my living room....

Indeed. Act now. Strike while the feeling is raw and the iron is hot!

Bravo!

Muchos gracias!

 

[elangoas]

Only a portion. My acoustician cares more about the fact that this isn't a truly dedicated HT room than I do :- ).

Cool

 

[ONEMANARMY]

I'm afraid, I've never used EQ. Just my two ears



Sounds good. Were you using EQ prior to passive room treatment? If so, how would you compare passive room treatment with using EQ alone?
[/QUOTE]

 

[elangoas]

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.

How much variation (dB) in bass (subwoofer) range is considered good to not apply EQ?..

 

[liverpool_for_life]

How much variation (dB) in bass (subwoofer) range is considered good to not apply EQ?..

This is subjective. It depends on how much variation you're willing to tolerate and/or how much room treatment (and additional subs!) your significant other is willing to tolerate. Relative to where I'm today, if I get to within +-5 dB between 10-80 Hz, I'd probably never leave my room. Ever!

So no, I don't have a "gold standard" number that'd be applicable for everyone. However, I do know that while completely flat from (say) 10-80 Hz looks great on a graph, people do seem to enjoy a bit of lift below 50 Hz (about 3-5 dB?) that gradually slopes down to flat around 80 Hz. "Perceptibly flat" bass has been demonstrably shown to be preferred to "measurably flat" bass.

"Measurably flat" is a good starting point though and then you can EQ to taste (my subs have a separate DSP program that provides the lift in the lower octaves I mentioned above). It is very hard to do though without a combination of multiple subs optimally placed, room treatments and EQ.

 

[matbhuvi]

"Measurably flat" is a good starting point though and then you can EQ to taste (my subs have a separate DSP program that provides the lift in the lower octaves I mentioned above). It is very hard to do though without a combination of multiple subs optimally placed, room treatments and EQ.

I have used extensive EQing in both passive and active setups in car. I have seen installers striving hard to get flat response curve. But, they were never to my tase. Nothing beats the un EQed sound for me. The moment you start the EQ, you'll alter the signature. Depending on the source/amp/speakers combination, you might or might not like it. For the same reason, i hat DSPs. Especially if your source DAC is good one. DSPs transform the source to just transport. All these experiences are in Car audio. But, it applies very well to home stereo as well. HT is different ball game. That requires good room correction.

 

[elangoas]

This is subjective. It depends on how much variation you're willing to tolerate and/or how much room treatment (and additional subs!) your significant other is willing to tolerate. Relative to where I'm today, if I get to within +-5 dB between 10-80 Hz, I'd probably never leave my room. Ever!

Ok. Thanks for the info.. I have a 15dB peak at 60Hz, in the 10Hz- 80Hz range.. Rest of the range is reasonably flat (per measurement).. Am still working on to lower the peak by re-positioning the subs..

So no, I don't have a "gold standard" number that'd be applicable for everyone. However, I do know that while completely flat from (say) 10-80 Hz looks great on a graph, people do seem to enjoy a bit of lift below 50 Hz (about 3-5 dB?) that gradually slopes down to flat around 80 Hz. "Perceptibly flat" bass has been demonstrably shown to be preferred to "measurably flat" bass.

I was looking for what is acceptable range of variation bet 10 - 80Hz..If am able to contain the peak at 60Hz to just 5dB, then i may not use EQ..

I like the bass, when there is no EQ applied (Audyssey), but that 60Hz peak is clearly audible.. So forced to use EQ to tame that.. The sooner am able to tame the peak, i will not apply EQ to bass range (10-80Hz)..

"Measurably flat" is a good starting point though and then you can EQ to taste (my subs have a separate DSP program that provides the lift in the lower octaves I mentioned above). It is very hard to do though without a combination of multiple subs optimally placed, room treatments and EQ.

Hopefully i get there..

 

[liverpool_for_life]

Work in progress:

 

[skdas]

Work in progress:

View attachment 34656

Very Nice, more pictures with details please.

 

[liverpool_for_life]

Ceiling done!

 

[liverpool_for_life]

Very Nice, more pictures with details please.

Thanks skdas! Of course, you've seen the completed pictures.

Virtually all of the work on the ceiling was to minimize the effect of flutter echoes. 3 panels (they are anything but, to look at!) were built of wood (to prevent rattling) with a porous black polyester fabric on top. The backing of the panels is composite material, including aluminium. The absorbent is Bonded Acetate Fiber, which is a bit like cotton and is what's used in their other installations. There are 4 1W LED's in the corners and they make me go 'Wow!' when turned on.

The panels are 4 feet by 2 feet, with the drop from the top of the ceiling to the bottom of the panel (including the mount) about 10 in. The panel itself is curved, with 4 in being the maximum thickness.

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

The biggest difference is higher playback levels. Dialogue intelligibility is noticeably higher, but still removed from my "no subtitles" criteria. There are lyrics in Tamil film songs that are now clear to me that weren't previously. Playback at lower levels is also now more clear.

I can't explain this, but the bank manager's gun shot in the opening sequence of "The Dark Knight" never sounded this good. And some subtle details that are now so well defined that you sit up and take notice (the string brushing up against the Joker's jacket as he looks to get onto the bus to drive off). Previously masked details now reveal themselves in all their glory (a telephone in the background in the 'Halena' song from Iru Mugan). Subtle? Yes. Feels awesome? Yes. Yes. Yes!

All of these changes have me grinning like I've got food in front of me. And, if you know me at all, that's my highest possible level of "grin" ;-)

Can't wait for the front wall to be treated next!

 

[liverpool_for_life]

So, had a chance to re-run ARC with the ceiling treatments in place. OMG!

Instruments: Their separation and impact is the best it's ever been in my room. Some of the liveliness here is breath-taking.

Vocals: As mentioned, clarity has gone up. However, tonality is just so much better. Rebecca Pidgeon in the Spanish Harlem was startlingly realistic.

Details, details, details. So much stuff that had been masked previously by the room have now sprung into life. IMO, there's great satisfaction in knowing that you have a good chance of hearing everything that's on the recording (speakers + room contributing to this). The littlest cues sometimes provide for the widest grins.

Played a couple of scenes from The Dark Knight (my go-to disc) at reference yesterday night.

Missus: The sound is no longer grating on the ears.
Me: Yeehaw!

My son, who isn't into music that much, has actually spent a fair bit of time in the room, listening to music. Listening, as in actually listening i.e. not with a book in hand and paying scarce attention. I even saw him nod his head a fair bit in response to the music. His verdict: The audio is so much clearer now. Indeed! As I told my acoustician: He came for the lights. And stayed for the music.