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Using energy time curve for acoustic analysis: developing a Home Theatre primer - Page 4

post #91 of 277
10/3/11 at 9:25am
Thread Starter 
Quote:
Originally Posted by test4echo101 View Post

Hey Mike,

Just a quick ?.
What settings are you using in REW to make your ETC graph lines so thin?
I've done like 10 etc measurements and my graph lines are big and fat no matter what i seem to do.
Test,

In the setting "view" tab there is a check box for use thick traces, mine was not checked, so they are "thin to win", not "thick to lick" - I'll keep my day job
(below is from HTS help page)
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post #92 of 277
10/3/11 at 9:34am
Thread Starter 
Quote:
Originally Posted by dragonfyr View Post

Are you using a full range sweep?

Do not band limit the stimulus.

Quote:
dragonfyr
New Member
Join Date: May 2005
Posts: 1

1 post in 6 years and this is what you have to say??
Please read thru the entire thread.


Frankly I'm suprised that AVS lets un-used registerations stay active so long, IMO they should delete any accounts that are registered and not used withing a 2 year period, seems like some alter-ego people may register 2-3-4 accounts, use 1 until they get banned/etc, then the next one....

I'll post a Q in the Forum Operations Center [edit - posted]
How many years do un-used accounts stay active?
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post #93 of 277
10/3/11 at 10:58am
Quote:
Originally Posted by dragonfyr View Post

The silence* is deafening...


(*which, ironically, the ETC could be used to evaluate!)

i see what you did there ....
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post #94 of 277
10/3/11 at 12:18pm
Glad you found an old account you could use

Now, On with show! Lets get this thread rockin!

I take it that REW requires a Set t=0 at IR peak and Use loop back a time ref checked.
Also, the audio card should be in a loop-back config.

However, If your NOT planning to use the string method, or a laser guided method from the capsule and instead use the blocking method, those requirement's become not as important correct?

So although it may be more work determining the ray path, one can still hunt down the reflection without a loop-back pretty accurately. It will just take more patience.
I've tried this (with a lot of help from some old guy) and found that for large reflections its pretty easy.
I also found that using progressively smaller blockers you can refine the area of incidence to a point where it you can make a pretty good guess where treatment is needed.

It is time consuming this way though. Just sayin.

I only post this because I have a cheap SB live card in my rew station computer and can't use a loop-back and get the real TOF info.

Test,
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post #95 of 277
10/3/11 at 12:19pm
Quote:
Originally Posted by mtbdudex View Post

In the setting "view" tab there is a check box for use thick traces, mine was not checked, so they are "thin to win", not "thick to lick" - I'll keep my day job
(below is from HTS help page)

Doh. I'm dumb.

Thanks Mike.
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post #96 of 277
10/3/11 at 6:24pm
Thread Starter 
Quote:
Originally Posted by dragonfyr View Post


Oh, and yes, they really should do something with those "old" user accounts!!!!

LOL, made my afternoon, Thx for staying around and contributing, seriously.

I'm in the basement HT right now doing sweeps 400-20khz, focusing on the ctr speaker, putting temp pieces of 2' x 4' 2" OC703 on the rear wall in various config, will post results later.

(my wife demanded her 24" iMac back into her craft room, which I'm using to take measurements, so tonight is last chance for 2 weeks....)

[edit] I'm gonna finish this tomorrow - posting graphs, uploaded to Picasa, now just gotta make an intelligent post....
Real reason: to watch the Detroit Tigers beat up on the NY Yankees!
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post #97 of 277
10/3/11 at 8:20pm
Thread Starter 
Quote:
Originally Posted by mtbdudex View Post


Quote:


Originally Posted by JohnM
You can't show a distance axis instead of (or as well as) a time axis (on my list of things to do though), but if you use the delta/zoom box it will show both time and the equivalent distance. To bring that up press the Ctrl key, hold down the right mouse button and drag.

Response from John.

Here is what it looks like, the delta/zoom box makes it easy to hunt down reflections, however for 1 person a royal PIA, really need a helper, I'll get my son to help later.
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post #98 of 277
10/4/11 at 9:49am
Thread Starter 
Quote:
Originally Posted by dragonfyr View Post

A couple thoughts.

Don't band limit. Just run a full out broadband sweep.

In the limits, try a setting of ~ X(time)-axis: -.2 -> 50 ms; Y(gain) axis: max 2-> min -35 dBfs.
As 50 ms corresponds to ~44.25 feet of travel, that should be fine to encompass the preponderance of the behavior in the space. that should 'zoom' in and window the display in a much clearer and more detailed POV for you as a good place to start.

The repeating spike intervals tend to suggest flutter echo Especially since you are running surround speakers (as opposed to a strictly 2 channel setup) you might consider applying a bit of absorption to the front wall and see if that does not mitigate that behavior. (Ordinarily I would use diffusion for flutter echo which only requires that the parallel surfaces be rendered 'less parallel' to stop the behavior as well as to retain the energy; but in this case the front wall may benefit from the absorption in order to also help damp early reflections from the surrounds. Note, this can all be determined with more certainty by running ETCs of all of the sources individually.)

Oh, and one more comment about the time scale.
Be careful in assuming that the time/distance, as displayed, corresponds to the actual time/distance of travel. The reason is that the direct signal arrive in the IR has been set to 0s. This translation of the axis neglects the time of flight (TOF) of the signal from the source speaker to the mic - in other words the TOF of the direct signal arrival has been effectively discarded - and it is a very real part of the time/distance of travel! Thus I would not opt for the 'set IR peak to T=0' option.

Hope that helps a bit...

Appreciate the help, some background on this purpose of this thread:
-For myself and others to learn and apply ETC, hence the title
-using my HT as the initial poster child for this - learn by doing, trial/error, hopefully with constructive feedback/guideance for experts in the field
-summarize my experiences as cliff notes, to re-enforce what I learned and help others start off more quickly to grasp the concepts and apply them

>>This thread is not just for me, I encourage others who are into the acoustic journey to do same in their HT/listening space and post their learnings/"light turned on" moments<<

My room layout and current treatments:


The big 130" screen is made from DW laminate, a acoustic reflection source.
The rear walls are not treated - yet, that is my first priority before I dig into the minute of fixing specific reflections.
I need to get rid of the front sound stage <> rear wall <> screen reflections, for now since I own OC703 that will suffice (in appropriate placement).
If as I gain knowledge, some of my RFZ goes from OC703 to other type of treatments, I'll cross that later, for now the treatments are paid and made, hung on the wall/ceiling, and doing some "good".

I'm focusing on the front soundstage LH/CTR/RH for now, one speaker at a time. Later, I'll do same for the side/rear surrounds.

I crossover the LH/CTR/RH at 80hz, so next time I'll run the sweep at 80-20khz as you suggested. The IB sub handles LFE.

Also, I'll look into "set IR peak to T=0" setting in REW tonight, I do understand your point.

Later, I will post the readings I took last night.
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post #99 of 277
10/5/11 at 1:36am
Thread Starter 
Quote:
Originally Posted by dragonfyr View Post

A couple thoughts.

Don't band limit. Just run a full out broadband sweep.

Quote:
Originally Posted by mtbdudex View Post


I crossover the LH/CTR/RH at 80hz, so next time I'll run the sweep at 80-20khz as you suggested. The IB sub handles LFE.

dragonfyr;
Lets discuss this in detail a little, why do you suggest full out broadband sweep?
Which is say 10-20khz?

My initial response of 80-20khz was written w/o considering the behavior of sound below and above the Fs transition range.

Above the transition frequency sound within a room is handled as a ray' hence I'm using ETC as a tool to analyze and fine tune the treatments from my RH/CTR/LH main speakers.

Below the transition frequency the behavior of the room is dominated by resonances' or modes and can be described through wave acoustics'

I've tackled most of my IB sub related LFE issues and plotted those in other thread
http://www.avsforum.com/avs-vb/showt...5#post20641105

Seems the calculation method for Fs is difficult for small rooms, so in general as a safe bet using below 200hz as LFE analysis (waterfall/freq plots) and above 200hz (ETC) are the correct acoustic tools?

Simply, if I include below 200hz won't 80hz-200hz LFE modal ringing/other show up on the ETC?
I could test that by doing ETC 80-200hz, ETC 80-20khz, and ETC 200-20khz and compare.

Just woke up to let the 9 month old puppy out for her morning "duty" and that thought came to me, so I'm posing the question here, thx.
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post #100 of 277
10/5/11 at 2:02am
Thread Starter 
Quote:


Also, I'll look into "set IR peak to T=0" setting in REW tonight

Took some screen shots of the REW Preferences Analysis tab, honestly I've never "dived deeply" into these settings before, I looked at then and left them at default for lack of grasping what changing them would do.

Will need some more study how they affect the graphs and the ETC analysis
http://www.hometheatershack.com/room...ponse.html#top
and here
http://www.hometheatershack.com/room...panel.html#top


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post #101 of 277
10/5/11 at 4:06am
Thread Starter 
Some "brute force" checks of the CTR speaker reflections back wall<>130" screen.

Set-up, what I did:
1) take baseling ETC readings w/o any "extra" OC703 on the rear wall,
2) then 1 panel centered long wise 4' long x 2' high,
3) then 2 panels,
4) then for "fun" stacked a 3rd panel above the 2 (as shown here), plots/results below.


I took measurements for all 1st row seats 1-4, will show seats 1-2 as the trend is same:
Seat 1, progressively 4 charts shown:








Seat 2, progressively 4 charts shown:








Now, I did NOT take readings in the 2nd row for this, I should have at least for 2 seat positions, and will in near future.

Clearly this needs addressing.

I read/watched that since my 2nd row is so close to the rear wall, about 18"-20" when reclined, I need to be careful on treatment, the thin QRD diffusers in the video seemed "ok" at that close.
For now, I have OC703 so will use that, just 2 panels not 3, no need to over absorb/deaden the room.
http://www.realtraps.com/video_diffusors.htm

http://www.realtraps.com/diffusor.htm
Quote:


The device transitions from diffusion to absorption over the range between 400 to 800 Hz.
The RealTraps Diffusor is 24 inches wide by 48 inches high by 6 inches deep and weighs 26 pounds [Metric: 61 x 122 x 15 cm, 12 kg].
It is available in either Far or Near versions, depending on the listener's proximity.
The Far version has diffusion wells 6 inches deep, and is recommended when the diffusor is at least six feet away from the listener's ears.
For smaller rooms where the listener is closer, the Near model is more appropriate.
The Near model has wells 3 inches deep, and the bass trap portion is correspondingly thicker as shown in the drawings above.
We can optionally build near style diffusors with a total depth of 3 inches when a thinner profile is needed.
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post #102 of 277
10/5/11 at 9:59am
MTX,

how often do you have a full house? (eg, how often are there humans in the 2nd row?)

if it is rare, may i suggest having a dynamic setup based on the number of users within the room?

design your diffusers and broadband absorbers to be mounted using the same dimensions and mounting positions - which will allow you to quickly swap out based on the number of users within the room.

if it is just the front row in use, keep the diffusers on the rear wall / rear side-walls.

if the 2nd row will be in use, swap the diffusers for the broadband panels.

the diffusers need space for the diffuse-field to develop - much to the same way you would not want to sit in the near-field of a multi-way speaker system.

some food for thought...
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post #103 of 277
10/5/11 at 10:16am
Thread Starter 
Quote:
Originally Posted by dragonfyr View Post

If the purpose of the diffusion is to address specific reflections off the rear wall by reducing their gain, I would personally opt for absorption, as the low order near field response will not be a significant improvement.

Also, you will note that the repeating interval peaks are gone with just 1 panel of OC703 on the rear wall, so I would stick with that. If you are adventurous, you may want to try experimenting with several smaller pieces of OC703 spaced on the rear wall to determine the minimum amount required to affect the same results. Note, in order to do this, you can use other material in the what if stages, as all you need to do is to disrupt the parallel surfaces that are supporting the back and forth reflection of energy. To this end another simple cosmetically acceptable option might be to employ a very low radius poly of 1/8” thick luan ply (~$9 at Lowes or Home Depot commonly used to face interior doors) - fashioned into a 4 foot or wider panel that extends say no more than 3 inches from the wall at its center should be more than adequate to disrupt the parallel surface flutter reflections

Thx for quick feedback, as I'll be in Japan next week won't have time to further pursue this till week of 10/17, however it always was my intention to add some visual to my room treatments, and doing back wall 2' x 4' 2" OC703 gives me the opportunity to use spoonflower printer cotton weave for the fabric, as dicussed in this thread, http://www.avsforum.com/avs-vb/showthread.php?t=1316623

Based on this discussion, my plan is (2) 2' x 4' 2" OC703 for the back wall visual, however I will surgically apply kraft paper to the front face of the OC703 to only absorb the energy where it is needed.
(will mount the 2 OC703 pieces un-wrapped, and using ETC then trial/error kraft paper coverage to confirm reflection reduction, then wrap the printed cotton weave and re-test with ETC final outcome)

Since my photo was NASA APOD for aug-5-2011, http://www.livingstondaily.com/artic...|img|Frontpage , that image will go on 1 panel, one of my other astrophotography photos will go on the other one, I've got a few to choose from as seen here http://photography-on-the.net/forum/...47#post9752647
I'll order those before my Sunday flight, so when I'm back that phase of this project can begin.

This is my NASA APOD for aug-5-2011:



Quote:
Originally Posted by localhost127 View Post

MTX,

how often do you have a full house? (eg, how often are there humans in the 2nd row?)

if it is rare, may i suggest having a dynamic setup based on the number of users within the room?

design your diffusers and broadband absorbers to be mounted using the same dimensions and mounting positions - which will allow you to quickly swap out based on the number of users within the room.

if it is just the front row in use, keep the diffusers on the rear wall / rear side-walls.

if the 2nd row will be in use, swap the diffusers for the broadband panels.

the diffusers need space for the diffuse-field to develop - much to the same way you would not want to sit in the near-field of a multi-way speaker system.

some food for thought...

Local;
I like your idea very much, in this case I might "give" some acoustical top notch performance as trade-off for visual look of images I took...

FWIW, I really do want to build diffusers , just to learn them and their application.
That will be a late fall/winter project. Even experiment with replacing my side wall absorbers for diffusers....
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post #104 of 277
10/5/11 at 10:32am
Quote:
Originally Posted by mtbdudex View Post

Based on this discussion, my plan is (2) 2' x 4' 2" OC703 for the back wall visual, however I will surgically apply kraft paper to the front face of the OC703 to only absorb the energy where it is needed.


why would you apply kraft paper on the rear wall absorbers?
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post #105 of 277
10/5/11 at 11:04am
Thread Starter 
Quote:
Originally Posted by localhost127 View Post


why would you apply kraft paper on the rear wall absorbers?

Based on my ETC charts only a single 2' x 4' panel centered was needed, however I desire to have 2 big 2' x 4' images displayed on the back wall.
Therefore, as simple thing I was going to cover 1/2 of each panel, the outside portion, so I can have my "cake" (echo control) and eat it too (art decorations on the back wall).

These will be simple, unframmed wrapped panels.
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post #106 of 277
10/5/11 at 11:10am
Quote:
Originally Posted by localhost127 View Post


why would you apply kraft paper on the rear wall absorbers?

Yea, wouldn't the Kraft paper cause further needless reflections?
I would not want HF reflecting off the Kraft paper very close to me.

Test,
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post #107 of 277
10/5/11 at 11:21am
Thread Starter 
Quote:
Originally Posted by test4echo101 View Post

Yea, wouldn't the Kraft paper cause further needless reflections?
I would not want HF reflecting off the Kraft paper very close to me.

Test,

RR wall is hard drywall only currently, reflecting, causes echo.
when I add (1) 2' x 4' 2" thk center located, mounted direct to wall solves the echo issue, per ETC chart.
If I add (2) panels, ETC shows does not add more value but then absorbs energy that might be considered "good" to have in the room.
Therefore, kraft paper on 50% of each outside makes that like the drywall again, just 2" closer, making (2) panels appear as (1) panel acoustically.
If ETC says that is worse than not, I'll remove it.
(maybe as I posted above you also posted, so missed my response to Local??)
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post #108 of 277
10/5/11 at 11:33am
Quote:
Originally Posted by dragonfyr View Post


Also, you will note that the repeating interval peaks are gone with just 1 panel of OC703 on the rear wall, so I would stick with that. If you are adventurous, you may want to try experimenting with several smaller pieces of OC703 spaced on the rear wall to determine the minimum amount required to affect the same results. Note, in order to do this, you can use other material in the what if stages, as all you need to do is to disrupt the parallel surfaces that are supporting the back and forth reflection of energy.

Hey Mark,

This is what i asked about yesterday. How small, can a panel be (if your accurate) to successfully remove a reflection.
We kind of got into a time and gain discussion....and never did come to a consensus as to how big a panel had to be to remove a reflection.

Of course a bottle cap sized treatment won't really help the over Sound Quality whether it be a diffuser or absorber, but I am only talking about a reflection.

So for instance, If Someone has 4 large reflections, One from the ceiling, one from the floor and 2 from the rear wall, how large a treatment would one need to remove those reflections?

Is this dependent on ones accuracy at finding the exact point of incidence or is there an FQ energy= time/gain relationship that determines how large a treatment panel must be?

Test,
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post #109 of 277
10/5/11 at 11:36am
Quote:
Originally Posted by mtbdudex View Post

RR wall is hard drywall only currently, reflecting, causes echo.
when I add (1) 2' x 4' 2" thk center located, mounted direct to wall solves the echo issue, per ETC chart.
If I add (2) panels, ETC shows does not add more value but then absorbs energy that might be considered "good" to have in the room.
Therefore, kraft paper on 50% of each outside makes that like the drywall again, just 2" closer, making (2) panels appear as (1) panel acoustically.
If ETC says that is worse than not, I'll remove it.
(maybe as I posted above you also posted, so missed my response to Local??)

Yea, sorry bout that. I must have posted as you were responding to local.

Test,
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post #110 of 277
10/5/11 at 12:35pm
Thread Starter 
Quote:


The purpose of the treatments is not to eliminate the energy, but merely to eliminate the parallel support of the reflection. To this end all that is actually needed is to bring one surface out of parallel. Although, depending on the situation, this situation can be effected by angling one surface, placing diffusion on one surface sufficient to redirect the energy into a non-parallel path, or absorption, which will reduce the energy return. Therefore all of the energy need not be effected and a large panel is not necessarily required. We only need sufficient modification of the reflective surface to cause a sufficient reduction in energy return to cease the reinforcement and continued reflections between surfaces.

So, how about this change in strategy then for rear wall to eliminate the parallel support of the reflection:

I get the printed sheets from spoonflower, mount directly to the 1/8” thick luan ply (simple wrap/staple on back), then curve and mount them to rear wall like you stated. Heck, that's easy to do.

I can still have my cake and eat it also this way, correct?

I'd still perfer (2) of these, side by side, for the visual appeal in the HT.

Of course, confrm via ETC results, adjust/locate as needed.

ok - I now see this also and will slow down...
Quote:


So, note the presence of flutter echo that is readily apparent from the ETC and simply file this awareness away for later reference. With luck, the natural progression of treatment will render this issue moot before everything is over.
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post #111 of 277
11/22/11 at 5:07pm
bump.

Yea i know its a 49 day old thread but its relevant.
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post #112 of 277
11/22/11 at 10:28pm
Interesting. I had started reaading this thread previously but then for some reason stopped. Probably occupied with amirm. What a waste.

Looks like aakkpthptht (will have to check the spelling on that!) has some thoughts similar to my own recently regarding the limitation/application of some of these models to a multichannel environment. Specifically in this thread, mtb is looking at lcr behavior. If similar value were assigned to surrounds, absorption might start showing up everywhere. Look at a 9 channel or worse lexicon's new 14 channel layout, and the room might start looking anechoic.
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post #113 of 277
11/25/11 at 1:35pm
Thread Starter 
Bigus, correct I'm focusing on L-C-R for 1st and 2nd row with the testing/acoustic tuning.

My side/rear surrounds are Paradigm ADP-390's, di-poles, for better or worse they are what I own.

After I'm done with L-C-R I will take ETC measurements of the side/rear surrounds to see what's going on, but as of now I have no plan to treat them unless something sticks out.

The surround sound actually is fantastic as is now, subjectively.
(listened to every track of scubasteve2365's "Home Theater Demo Disc - Version 2.0" last week with friends from Spain)
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post #114 of 277
11/28/11 at 11:30am
Quote:
Originally Posted by Bigus View Post

Interesting. I had started reaading this thread previously but then for some reason stopped. Probably occupied with amirm. What a waste.

Looks like aakkpthptht (will have to check the spelling on that!) has some thoughts similar to my own recently regarding the limitation/application of some of these models to a multichannel environment. Specifically in this thread, mtb is looking at lcr behavior. If similar value were assigned to surrounds, absorption might start showing up everywhere. Look at a 9 channel or worse lexicon's new 14 channel layout, and the room might start looking anechoic.

I'm not even caught up yet. LOL @ occupied w/ amirm.

My understanding is that THX processing applies some sort of decorrelation to the surrounds. That indicates to me that rather than removing the (essentially decorrelated, if I get my understanding right) specular reflections, we would want to either leave them or possibly further decorrelate by using diffusion at those points. The latter is what RPG room-whatever-it-is software has you do. Also it makes sense given what dipole speakers were attempting to accomplish (let me know that I'm not current on THX recommendations and have been told they don't recommend dipoles any longer - but also have not verified). Anyway you'd be looking more for the exponential smooth decay and not an ISD gap - certainly with energy up into the ambience region and possibly even some up into the image smearing region maybe (even wilder speculation than the rest from me here though).

I also suspect that while the approaches we have been discussing are appropriate for "normal" speakers (ones with uneven dispersion and/or different sound off axis and/or lots of cabinet diffraction etc), they probably aren't if using speakers with either more tightly controlled dispersion or specifically designed to have very consistent wide dispersion. I'm not entirely sure of the specifics but I believe that is what D.E. would say.
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post #115 of 277
11/29/11 at 7:46am
Mike,
Just checking to see if you were able to get your measurements done?
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post #116 of 277
11/29/11 at 9:26am
Thread Starter 
Quote:
Originally Posted by fotto View Post

Mike,
Just checking to see if you were able to get your measurements done?

Floyd;
Nope , blame it on.....good weather we had over Thanksgiving break, yep.

I re-stained our loghome this past summer, and noticed the log ends at all the corners needed re-caulking + backer rods to seal them from air infiltration into our home.
(circled in red, this pict from summer July-2011 re-staining, 50 foot boom crane)

So, with 4 days of weather in the 50's got that task done, took 7 tubes of caulk, backer rods to fill the larger end gaps, and lots of time on ladder.
up/down, up/down..Hopefully save some $$ on winter heat bill


I was "burned out" after getting that done Saturday, so just relaxed.

It's definitley on my HT to-do task list.
In reality, just need a solid 2-3 hours to re-do the measurements......
All the cables are still attached, mic/boom stand in room, etc.
(frankly I need to get the acoustic's "done" so I can clean up and put that gear away)
I'll probably just "burn the candle" and stay up late after putting kids to bed as a weekday thing, the weekends we watch movies there/etc.
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post #117 of 277
11/29/11 at 1:04pm
I hear you man...just not enough time in the day.
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post #118 of 277
11/29/11 at 10:15pm
Quote:
Originally Posted by localhost127 View Post

MTB,
the reason for attenuating to -20dB or greater is to eliminate it from the detection threshold.



by having the early reflections be below the threshold, the brain is no longer trying to localize them... it is not the 'hearing' threshold per se' (-20dB doesn't mean unhearable), but the trigger level. attenuated early reflections below this trigger threshold means they are no longer competing with the direct signal for your brains focus re: localization.

Blanket attenuating reflections by 20 db is not the way to go. Just because something can be detected does not mean that it is bad. Quite the contrary...many listening studies as referenced in toole's book show that we subjectively prefer higher levels of reflections. They add body and fullness to instruments and increase the ears ability to perceive timbre. Now if you said 'this is one philosophy' of how to treat a room to deal with reflections then I would agree with you. But it is not the only one, and nor do I think for most domestic listening situations is it the right one.
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post #119 of 277
11/30/11 at 6:05am
Quote:
Originally Posted by Nyal Mellor View Post

Blanket attenuating reflections by 20 db is not the way to go. Just because something can be detected does not mean that it is bad. Quite the contrary...many listening studies as referenced in toole's book show that we subjectively prefer higher levels of reflections. They add body and fullness to instruments and increase the ears ability to perceive timbre. Now if you said 'this is one philosophy' of how to treat a room to deal with reflections then I would agree with you. But it is not the only one, and nor do I think for most domestic listening situations is it the right one.

re-read my quote again:

Quote:
Originally Posted by localhost127 View Post

by having the early reflections be below the threshold, the brain is no longer trying to localize them... it is not the 'hearing' threshold per se' (-20dB doesn't mean unhearable), but the trigger level. attenuated early reflections below this trigger threshold means they are no longer competing with the direct signal for your brains focus re: localization.

what specifically with this direct statement you quoted do you disagree with? or are you reading more into it than what was explicitly stated.
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post #120 of 277
11/30/11 at 7:33am
Quote:
Originally Posted by Nyal Mellor View Post

Now if you said 'this is one philosophy' of how to treat a room to deal with reflections then I would agree with you. But it is not the only one, and nor do I think for most domestic listening situations is it the right one.

Quote:
Originally Posted by localhost127 View Post

you modify your room as needed to achieve the particular room response you desire -

doh!

if one is adhering to a specific room response (model) - or allowing the room to function as is/un-treated, then that is the user's decesion.
the user in the context of THIS thread has MADE THE DECISION to attenuate early reflections - of which a primer was born on the usefulness of the ETC to determine and identify such high-gain early specular reflections, and to use the ETC to re verify the problem has been resolved once the treatment has been procured and placed.

it's almost as if every time someone asks how to use a hammer to specifically build a bird-house, another user has to chime in and ask why one is even building the bird-house in the first place - and that perhaps a dog-house may be a better choice.
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