Acoustical Treatments Master Thread - Page 314

Well it looks like it wont make much difference at all according to the graph. Green is with the OC705 and a 10" air gap, which is what I have now. Blue is with the OC705 and 10" of pink fluffy insulation behind it.http://www.stanleyhallstudios.co.uk/pacalc/pacalc.php?m=4&s11=2&d11=101.6&v11=30000&s12=2&d12=254&v12=5000&s21=2&d21=101.6&v21=30000&s22=1&d22=254

I'm thinking of treating my front wall. I have the main speakers + 2 dedicated subs up front and was wondering whether to use bass traps in the corners or 4" x 24" x48" bass trap panels or regular 4"x 24"x 48" panels behind the speakers.Since I only have 3' from the corner to the screen, I can choose only one. My room is approx. 15'x 29".I will also be adding bass traps in the rear corners of the room. I should also add that this is a dedicated basement theater room with 7.2 sound used mainly for movies. I have direct radiating speakers up front with bi-poles for surrounds.

Thanks,
Ken
Edited by Kensmith48 - 3/5/13 at 1:43pm

Take a look here instead: http://www.stanleyhallstudios.co.uk/pacalc/pacalc.php?e=h&r=r&m=4&s11=2&d11=101.6&v11=30000&s12=2&d12=254&v12=5000&s21=2&d21=101.6&v21=30000&s22=1&d22=254

(Note: it will take a bit to load - maybe up to 30 seconds)

You'll notice a bit different of a graph. I chose high resolution first off, which wouldn't change it too much, but I changed it to random incidence. Since the absorber is in the corner where sound waves won't be directly going into it (as opposed to a reflection point where a lot of energy is going into the absorber), this gives a better calculation. The difference isn't usually 'huge' but with how cheap fluffy is, its usually worth the slight improvement.

In case your curious, the long load time is due to the high resolution option.


I would go with the corner treatment. Modal resonance usually is a bigger factor than SBIR nulls when you have two subs. Using two subs helps to flatten out the nulls with careful placement, but modal resonance will still exist regardless of where you put your subs. So I'd go with thick corner traps - floor to ceiling if possible. Hopefully that makes sense!


Wow, that is one thin room!

OK, I realize this post is 10 years old, but I was wondering if Dennis (or anyone else) has an opinion on 7ch vs 9 or 11 channels for music playback in an appropriately treated room, optimized for movie playback.

In other words, will the extra channels provide benefit when listening to 2 ch music (with dsp providing the room sound via the surround channels).

Also any opinion for movie playback in 9 or 11 channels in a treated room? FWIW My theater is going to be large at 38x28ft and I will be using commercial theater speakers with 90x40 constant reflectivity horns. And yes I realize 99.786% of movies are only 5.1 and the extra channels are synthesized using DSP.

http://www.cepro.com/article/speaker_engineer_questions_home_theater_equalization_process/?utm_source=CEPWeekly&utm_medium=email

That is so true

He misses a big distinction when he says "You don't tune a Steinway for the room." And that is, do you want your sound system to replicate instruments played in your home or do you want it to be a window into another world... another environment entirely? And, recordings have to be produced for each application, with the vast majority of recordings intended as windows into another world. They add reverb, eq and other things to control the feeling of space and environment.

When setting up our home theaters, we most definitely want the "window into another world" effect. Skyfall isn't being blown to bits inside our tiny little theaters. It's being blown to bits in a wide open plain. Our walls should disappear acoustically and the surround speakers should create the environment intended.

I think he really misses the point.

Thanks. Not being a pro, I hesitated to weigh in, but there is a difference between an instrument producing a note and a system REproducing that note.

Wow. Was that really 10 years ago? I remember reading that post when it was written, and looked forward to seeing which surround modes were most useful for music. I haven't seen much written about it, but I would be interested in hearing which surround modes people find best for music in a room treated for home theater.

Considering our systems are only performing in one venue(our particular home theater), I don't think it's a waste of time to optimize for it.

That optimization should include treating the room though, but then there is no Automatic Audyssey Physical Room Correction, is there?

Paul Hales, or the author, is making profuse use of "glittering generalities". Bad form.
Yes, poor microphones, lack of understanding what the instrumentation is telling you, and failing to listen are widespread faults; but, ignoring the fact there are professionals available is a big miss. I share his view that "automagic" systems frequently do a poor job; but, the very existence of these tools is telling the consumer audio calibration is necessary.

The whole Steinway analogy is a big miss (besides, use a real piano like a Bosendorfer ). As has been said above, properly tuning an instrument is a radically different objective than attempting to reproduce the recorded sound of that piano and venue in some other space.
Edited by Dennis Erskine - 3/24/13 at 5:38am

Addendum .... Bosendorfer may not tune their pianos to a room; but, they are very picky about the acoustics of the rooms the use to showcase their instruments:

Since October 2010 the new BÖSENDORFER-SAAL im MOZARTHAUS VIENNA *) is running. It is the third one in the history of Bösendorfer and it is situated in the Mozarthaus Vienna, right in the city center of Vienna near St. Stephan's Cathedral. (Stephansplatz)

The beautifully designed hall in the vaulted cellar of the building of Mozart's flat in Vienna, has excellent acoustics and is equipped with a Bösendorfer Model 200.

I actually have two surround speaker configurations that I manually swap for hi-res multichannel music or everything else. (The qualifier would be that the music is mixed from an in-the-band perspective.)

The MCH music config is five identical monopoles with the surrounds at 120 degrees. There are monopole rear surrounds at 180 degrees, but they rarely have anything to reproduce. In the cinema/concert/TV the surrounds are tripole at 90 degrees (and those monopole rear surrounds). Along with swapping speaker connections, I load Audyssey calibrations for each speaker configuration.

My own listening tells me that a system optimized for movies does not work for in-the-band suround music mixes as all channels can carry the same full range/full power content and, as far as I know, is MIXED with surrounds at 110-120. And the corollary is that I find watching movies with this config to be somewhat disturbing; the surround content is too "direct" and is coming from the wrong direction.

Admittedly, this scheme is not an elegant solution and is a bit of a pain to switch when guests are here and we are trying to make the most of our time together. But most of my home theater use is solitary ... with the two type of content the same for any given session.

Jeff
Edited by pepar - 3/24/13 at 8:26am

I got a chance to listen to some 2-channel music in an Erskine-designed theatre last year. Can't say if it was specifically "treated for home theater", but it was carefully tuned using a combination of placement, treatment and equalization. Of the surround modes we tried, PLIIx Music mode turned out to be my preference. The amount of surround extraction is user-adjustable, and it was dialed in to make effective use of the surrounds without ever calling attention to the surround speakers themselves.

The end result was a wide, lush soundstage that appeared to stretch beyond the side walls of the room; exactly what I want when listening to 2-channel music (except it took more than 2 speakers to achieve that result). The combination of PLII/PLIIx Music mode and a well treated room sound excellent for music listening, especailly since you can tailor the results to your personal preference (user-adjustable centre extraction and surround extraction).

I appreciate the input. Exactly what I was looking for!

That sound encouraging. Strangely enough I find myself with twelve identical Altec A6 Voice of the theater speakers. I only wanted to buy four pairs, but it was an all or nothing deal. So I guess I may as well go ahead with 11.2. I just wish there were some 11.2 pre/pro options.

Just two of these puppies were hitting 115db peaks in my seat, twenty feet away, with around 100watts each... and sounded amazing all the while. The garage (1/2 of the future HT) has 12" of fiberglass insulation on all but the floor and the back garage door. Guess it must smooth the room response, because I have NEVER heard bass like that outside of a live out door concert. Wife and kids didn't hear a thing in the main house (a dream come true!)

I don't have a wide angle lens, so I couldn't get everything in, but you get the idea... These were taken out of a theater in Alaska that closed down.

Hi Kevin,

I have an Erskine designed room with a 9.5 Procella system and I would never ever listen in stereo again. PLIIx music mode sounds glorious !!

Cheers,

Those are some big speakers for home theater lol. Will be pleanty of sound!

Cool, pro speakers!

Sounds awesome, thanks for chiming in! I used to live in Rose Bay. Sydney is such a beautiful city.


You should see the subs . I have a 30x40ft detached building to devote to HT this time round, so it shouldn't be too hard to hide them. They're pretty shallow, ~ 1.5ft and 7 of 11 go on the front wall.

Fantastic! I'm planning on going Procella as well, but probably not 9.5!!! Looking forward to trying PLIIx.

The only one I can think of is the recently released Marantz 8801.

Very nice woofers, especially for their time. Their combination of sound, efficiency and deep bass response (in a properly large box) is unmatched. I'm a great fan, having purchased my first pair of 416-8A's from Electronics Plus (in San Rafael) in 1978 for $95 each! And, I still have them in my living room speakers system. They work like the day they were new. But I've never been a big fan of their horns. Instead I pair them up with Dynaudio D-76's and Esotar D-260's in a tri-amp'd configuration so efficiencies and phase match. It's all very sweet.

I, too, bought a batch from a closing theater (in Oregon) and used 8 of those for an IB sub. They did a very credible job, but I later swapped them out for a set of AE-IB15's, which do a very incredible job!

EDIT: BTW, my 416's -3dB point is 18Hz in their 6 cu. ft. box!

Procella had the second best sounding demo at CEDIA two years ago. It sounded incredible, but second nonetheless IMO.
Edited by pepar - 3/25/13 at 9:21am

Yeah....and they were using some experimental acoustic treatments...the experiment didn't measure up. Now they are using Quest treatments. Last year was a big improvement.

The Denon 4311 does 11.2 as well.

Right, but he was asking about pre-pros.

LOL ! It certainly is if you live in Rose Bay !!!

Pepar,

I was at CEDIA two years ago. Which room did you think was the best ?

Cheers,

I had a near-religious experience in the Wisdom Audio demo. While they did come in in the wee hours of the morning when the venue was quiet and do an Audyssey Pro calibration (MultEQ XT), they had no room treatments other than some bass traps. Otherwise the room was the same cheap carpet-covered popup traveling box you find at trade shows.

I was not in the sweet spot, yet the imaging was spot on. The female vocal (I forget who) was as present and immediate as if she was singing live. All the instruments had a presence that I had never heard before in a home theater. Of course the speakers were $30k - $40k EACH so short of a Powerball win, I will never own them. But that hasn't lifted the curse from me. I did recently check back at their site and found that they have introduced a more affordable line of speakers that I am anxious to hear. I *think* it is their planar magnetic technology that made the difference, so I am hoping that the new line of speakers "captures the essence" of their high end.

Jeff
Edited by pepar - 3/26/13 at 8:37am

Which one was first?