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post #61 of 292 Old 09-27-2011, 03:39 AM - Thread Starter
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Quote:
Originally Posted by localhost127 View Post

that can't be right...far too low.
focus on 0-300waterfall plot, and ETC (time-domain) above that...

regarding this link:
http://www.linkwitzlab.com/rooms.htm

the gentlemen is quite concerned with rt60 times, critical distances, etc - of which are irrelevant in small acoustical spaces because a reverberant sound field does not exist in small acoustical spaces.




there is no statistically random incidence in a small acoustical space.

http://www.hometheatershack.com/foru...rt60s-sas.html

you should be wary anytime someone discusses such with regards to small acoustical spaces...

localhost127;
All my measurements last Saturday/Sunday were taken at 200-20khz, future ones I'll re-take at 400-20khz, per http://www.realtraps.com/art_measuring.htm.
Quote:


I separate room acoustics - both measurements and treatment - into two frequency ranges: bass below about 300 or 400 Hz and mid/high frequencies above 400 Hz.

I've read that page before, my bad at forgetting...

I do realize RT60 is for "large" acoustical space, not small acoustical space like my HT (and most other HT here).
I've moved past that long ago, just when a long established maker/user and respected expert like Mr Linkwitz uses that in an equation I was hoping it would help me estimate/forecast Fs for my room.
http://www.linkwitzlab.com/about_me.htm

Are you aware any methods to estimate/forecast Fs for small acoustical spaces? Not a deal breaker, just curious.

What I don't like about HTS, when they ban/remove people, I can't find other posts from them, like "mas", the one who wrote the thread you linked above.
(there may have been a good reason for HTS removing "mas", I just want to see other posts by him/her)
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post #62 of 292 Old 09-27-2011, 09:50 AM - Thread Starter
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Quote:
Originally Posted by aackthpt View Post

Use of ETC has been explained here fairly completely I'd say. I think the question now is, how to best apply it in a home theatre room (given that this is a home theatre forum)? Possibly a better question: where does Mike (OP) wish to take the thread now?

Re-read during lunch, and realize I never did respond to this....

My original intention stands:
"Using energy time curve for acoustic analysis: developing a Home Theatre primer"

I will carry this topic thru until I am "satisfied" with the acoustics in my HT, based on objective data (ETC, etc), and subjective listening.

When that happens then I'll "move on" to other stuff.
It may take 1 more month, it may take 3 months, busy with kids/stuff/life, but I won't be accused of starting something and not seeing it thru the final conclusion.
That's the OCD in me, seeing something thru till it's logical conclusion.
(like many others here as well)
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post #63 of 292 Old 09-27-2011, 10:07 AM - Thread Starter
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Graph sharing time:
These were all at 200hz-20khz:

I did all 3 front speakers seperately (LH, CTR, RH), for seats 1-4 in the 1st row only, thru the "Ext In" so no processing at all, just raw speaker/room interaction.

I was doing quick test to see if the "hard" edges on my 2' x 4' acoustic panels were causing noticable reflections, so each seat has the base test (with side panels as they are), and 2nd graph is with the added pieces of OC703 which would negate reflections the wood edges induce.
(and the piece on the screen would negate the screen edges also, but not the DW laminate reflections)


LH Frt Main speaker:
Seat#1


Seat#1 with added temp (4) sheets of 2" OC703



Seat #2


Seat#2 with added temp (4) sheets of 2" OC703



Seat #3


Seat#3 with added temp (4) sheets of 2" OC703


Seat #4


Seat#4 with added temp (4) sheets of 2" OC703


My conclusion:
1) For my install, set-up, room interactions, speaker layout/toe in
>> having "hard" wood edges on my 2' x 4' x 2" + 2" air gap acoustic panels did not affect their performance where by I could clearly see it on the ETC charts.
2) I do see some spikes that indicate possible hard edge issues elsewhere in the HT, or those may be 200-400hz modal ringing issues that show up. When I re-do the ETC's @ 400hz-20khz will know for sure.

Next posts:
RH speaker and CTR speaker.
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post #64 of 292 Old 09-27-2011, 11:27 AM
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hard to see detail in the 0-50ms range without being zoomed in.

why is there a specular reflection in seat #1 *after* adding OC703? (looks like around 8ms; -10dB down). can you hunt it down with the string test?

when you say "bare side wall", is that test with all panels removed from the room?
edit: just re-read - the bare side walls are WITH the broadband panels in place. i'd always take BASE measurements with NO panels in place just so you know your 'original starting point'.

it would be a good idea to start with a completely bare room (disregard corner bass traps), measuring, and then adding a panel, remeasuring, etc rinse and repeat. that way you can see what energy specifically each panel attenuates, and by how much (-X dB) with the before and after ETCs. this can be cumbersome for many listening positions, so i'd just focus on the primary/single listening position for now. but seeing how "cluttered" the original room was before any panels were added may be beneficial in the final before and after graphs


Quote:
Originally Posted by mtbdudex View Post

2) I do see some spikes that indicate possible hard edge issues elsewhere in the HT, or those may be 200-400hz modal ringing issues that show up. When I re-do the ETC's @ 400hz-20khz will know for sure.

no modal issues within the ETC. use the string test and physically verify what boundary or source the energy is incident from.
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post #65 of 292 Old 09-27-2011, 11:42 AM
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also, did you place a blanket or anything between the mic and the highly reflective couch? -cant tell from the photo.
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post #66 of 292 Old 09-27-2011, 12:44 PM - Thread Starter
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Quote:
Originally Posted by localhost127 View Post

it would be a good idea to start with a completely bare room (disregard corner bass traps), measuring, and then adding a panel, remeasuring, etc rinse and repeat. that way you can see what energy specifically each panel attenuates, and by how much (-X dB) with the before and after ETCs. this can be cumbersome for many listening positions, so i'd just focus on the primary/single listening position for now. but seeing how "cluttered" the original room was before any panels were added may be beneficial in the final before and after graphs

100% agree - in ideal world. Real world is busy dad with 3 kids, soccer saturdays, cub scouts/girl scouts weekdays, yadda-yadda.
If I had a "helper" who'd come over together we could take all 6 side wall panels off AND my 2 12' x 2' acoustic ceiling clouds out for true baseline, and reflection hunt down.
I can't remove/install the ceiling cloud by myself, that's where the helper comes in, along with the reflection hunt down, a 3rd hand would speed up things.
(my wife helped with the ceiling cloud install on ladder, but doing this will take too much time)

Planning:
Add each acoustic treatment 1 at a time, and take reading in seats 2 and 4 for each speaker.
2 seats x 8 panels x 3 speakers = 48 readings too much time.

That's too many measurements, being more pratical:
1 seat x 5 panels (2 LH + 2 RH + 1 ceiling for 1st row only, leave 2nd row treatments out) x 2 speakers (LH and CTR) = 10 measurements
>>0.5 hour removal time, 1.5 hour replace/measure time, give 0.5 hour for "do-overs", budget solid 3-4 hours for this.

Possible to also "bunch" the 2 RH and LH panels into just 1 install, then:

1 seat x 3 panels (LH set + RH set + ceiling cloud) x 2 speakers = 6 measurements

Quote:
Originally Posted by localhost127 View Post

also, did you place a blanket or anything between the mic and the highly reflective couch? -cant tell from the photo.

These ETC charts were all done Saturday 9/24.
1st row couch was lowered with almost 12" mic clearance, but "no" - at this time I had not put blanket on 1st row couch or 2nd row couch. That will be added to next round of measurements procedure.
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post #67 of 292 Old 09-27-2011, 01:02 PM
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Quote:
Originally Posted by mtbdudex View Post

100% agree - in ideal world. Real world is busy dad with 3 kids, soccer saturdays, cub scouts/girl scouts weekdays, yadda-yadda.

understood - loud and clear!
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post #68 of 292 Old 09-27-2011, 01:48 PM - Thread Starter
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Ok;
lets learn how to read and interpret an ETC, for discussion sake.
Seat #2 chart with all my treatments currently in place, what can we learn from this?


a) I see a -20db drop almost immediately afterward, is that "good" or "bad"?
What is our criteria for "good" and "bad" for that?
(or whatever judge criteria there is)

b) then, I see a -15db/50ms slope of energy being absorbed/lost/reflected/etc via simple extrapolation of the chart thru the first 225ms, my swag. Again, how do I interpret that as "good", "bad", "acceptable" but could be improved, etc.

c) I plotted the Schroeder integral, what insight can I gain by that non-linear (squiggly) curve?
From REW:
Quote:


Schroeder Integral
The Schroeder Integral is a curve obtained by backwards integration of the squared impulse response, ideally starting from a point where the response falls into the noise and applying a correction (a starting value for the integral) which assumes the rate at which the Schroeder curve is falling continues for the whole response. REW uses an iterative procedure to estimate the best starting point for the integration, often called "Lundeby's Method" (from the paper by A. Lundeby, T. E. Vigran, H. Bietz, and M. Vorländer, “Uncertainties of Measurements in Room Acoustics,” Acustica, vol. 81, pp. 344–355 (1995)). The slope of this curve is used to measure how fast the impulse response is decaying, deriving a figure for "RT60" which is the time it would take sound to decay by 60dB. The curve shown on the Impulse graph is for the currently applied filter, if any. When calculating decay data for the octave and one-third octave RT60 results the impulse is first filtered to the corresponding bandwidth and centre frequency before the Schroeder Integral for that band is determined and the various RT60 measures calculated.

d) -36.4 db FS at the bottom of the chart, what does that mean/imply?
[edit] I see it varies as I change the let/right graph limits...still why does REW display it unless some significance/info to grasp?


This is part of the process, understanding the data presented in the chart, so I'd like to grasp that clearly.
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post #69 of 292 Old 09-27-2011, 02:44 PM
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Quote:
Originally Posted by mtbdudex View Post

This is part of the process, understanding the data presented in the chart, so I'd like to grasp that clearly.

And you're far from alone. Thanks for being the guinea pig.
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post #70 of 292 Old 09-27-2011, 03:59 PM - Thread Starter
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ok;
I found answer to a) above via http://www.realtraps.com/art_measuring.htm

So, -20db is "better" than 10-15db softer than the initial direct sound.
Check.

Quote:


Envelope Time Curve (NM)

The measurement below shows sound pressure level on the vertical axis and time on the horizontal axis. The graph is sometimes normalized so that the direct sound received from the loudspeaker is set to 0 decibels (dB) and 0 millisecond (ms). This chart, taken from FuzzMeasure, has not been normalized.

From this graph you can see the level and time of reflections from room boundaries and other objects within the listening room. The target for this measurement is typically that the level of reflections should be at least 10 to 15 dB softer than the direct sound.

Let's pretend there is a strong reflection at 10ms after the direct sound - the left-most peak at 8 ms on the chart below. To find where this is coming from in a room you will need to convert time into distance. The speed of sound is 1,125 feet per second (i.e. the sound from your speakers travels 1,125ft in one second). That equates to approximately 1.1 feet per thousandth of a second (i.e. 1.1 feet per ms). So in 10 ms the sound has traveled 11ft. You should then look around your room to identify the boundaries or objects that are causing the reflection. Remember that the sound has to travel to and from a boundary before it reaches the microphone position.

Once you find the boundary in question then you can determine if that reflection is problematic and should be treated. Some reflections are not necessarily problematic (e.g. side walls away from reflection points), and there are different options on how to treat the reflection (it can be absorbed or diffused or reflected away).


This is a very good read, into it now; "A Sound Engineer’s Guide to Audio Test and Measurement, Glen Ballou"
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post #71 of 292 Old 09-28-2011, 10:03 AM - Thread Starter
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Lunchtime thoughts/postings:

RH Main Frt ETC charts -from 9/24 readings & set-up method, same as above post:

RH Main Frt seat 1


RH Main Frt seat 2


RH Main Frt seat 3


RH Main Frt seat 4


All I'll say about the RH side is I know there are reflections, and my IB sub/ A/V rack located behind the RH speaker can't help much....I'll leave that dig-out analysis for later (and re-do @ 400hz-20khz)
(seen in this pre-LH corner bass trap pict)


CTR Main ETC charts -from 9/24 readings & set-up method, same as others:

CTR Main seat 1


CTR Main seat 2


CTR Main seat 3


CTR Main seat 4



There is a LOT going on with the Ctr speaker, and these ETC charts show it, flutter reflections! More so, I hear them at times.
It's on my to-do list to treat the rear wall, currently it is NOT treated at all.
Look here (I've got brown kraft paper on those corner bass traps to not over absorb the room at mid-hi freq):


As temp test I'll put some OC703 loosely there via just laying on the 2nd row seats and re-test.

My plan for rear walls was diffusor (type/design tbd), but I'd be quite nearfield to them for 2nd row, like 18"-ish from ears.
From what I've read in that case 2" OC703 directly on the rear wall works better, or space it if more low bass absorb is needed, but I'm decent in that regards so simplest direct mount to wall would suffice there.


Other:
To gain a more intutative grasp of "bad" reflection spikes on the ETC, next time I'll bring some big/hard board and put that in the sound path to see how it affects the ETC, as trial in learning how to read.
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post #72 of 292 Old 09-28-2011, 11:00 AM
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aligning with the schroeder integral is in essence attempting to have an even, exponentially decay field.

you'll notice you still have lots of little 'hot' (in gain) specular reflections poking up.

modeling your ETC to look like some ideal response is not necessarily what you're after.

you're doing a few things.

0) you're now actually able to physically measure and SEE just how energy is impeding and decaying with respect to a listening position. for example, you said you could 'hear' that flutter between the front and rear wall with regards to the center speaker. now you have measurements showing the anomaly, and will have measurements once you fix the issue. you now have the visibility.

1) verifying that your broadband traps are truly (measured) attenuating the specular reflections of which they are designed to do. this includes VERIFYING with the ETC that the reflection is indeed attenuated to the appropriate levels (eg, if you had a design requirement to keep everything -20dB down)...and that the panels are attenuating this reflection across the entire listening position.

2) you are able to actually see how the specular energy behaves and DECAYS within your room.

3) you can see the effect that a diffuser has at breaking up a loud (measured) specular reflection in the ETC (and turning it into a diffused energy return, decaying with time)... this is why i always ask what 'tool' people use to show what their diffusers are doing within the room - the ETC is the tool to do just that!

4) on some of your graphs, it looks like there is some very early energy (like 1-3s after the original signal)



compare that with this where it is a clean drop-off after the original signal (besides that reflection around 8ms):



you would likely want to hunt this down...again, you need to zoom in further (0-50ms) to have some resolution.


now, generally, you attenuate these early reflections for a length in time (ISD-gap) - which removes the time-smearing of early reflections when the brain is unable to distinguish an early reflection as being a distinct, separate signal (echo). since these reflections are attenuated, then they are also NOT combining at the listening position with the original signal to cause constructive and destructive interference (comb-filtering).

if you were to remove all the panels within your room and take a frequency response in the specular region, you would see this comb-filtering. as you attenuate the early reflections, this will diminish. this is why you treat specular frequency response issues with regards to the time-domain with the ETC! it's a bit backwards but once you see the reason for those freq-response anomalies (reflections + summation with the original signal at the listening position), and you remove (attenuate) these early reflections with respect to the time-domain and the ETC...then you are using the time-domain to clear up the frequency-domain. make sense?

now, when you attenuate these reflections, you're essentially creating an 'effectively anechoic' space for that length in time. it isn't anechoic, but it is effectively anechoic as when the energy is below -20dB or more, you will not be able to hear it (below detection threshold level). now, if the goal was to create a dead room then you would simply attenuate all of this energy - but the goal is not to create a dead room!

once this 'effectively anechoic' (ISD) time period is over (of which whose length gives the perception of the size of the room), you want to RE-INTRODUCE the energy back to the listening position. hence, you are terminating the ISD (the anechoic period is now OVER - and energy is now re-impeding the listening position). when energy is reintroduced either by a loud specular reflection or a loud diffused return, it will reinforce the localization cues of the direct energy (your brain will lock on to the direct signal from the speakers). now, since this is a small acoustical space - the remaining energy bouncing around the room still has a direction component - which can confuse the brain (eg it's hearing 'loud' specular reflections/signals from directions OTHER than the speaker as that energy continues to bounce around the room). the reason why the termination and a diffused decaying sound-field is important is to remove the localization cues from this energy.

Quote:
Originally Posted by SAC View Post

The termination of the ISD does several things as well psycho-acoustically. It provides the sense of liveliness to the listening space. Second, it aids in localization by 'removing' the localization and tonality shifting cues from later arriving signals - causing the focus and localization to lock onto the direct signal. And the later arriving exponentially decaying diffuse soundfield adds to the sense of space/size to the listening environment.

re-read some of the commentary in post #25:
https://www.avsforum.com/avs-vb/showt...8#post20832678

pick a 'hot' (high gain) specular reflection on the ETC. do the string test and trace out what boundary or object that energy is incident from.

for example in this measurement:



what is that hot reflection at ~60ms??
also, why are you now seeing energy at around 6-8ms *after* you added the sheets of OC703?

another *gotcha* that you could be taking away from this exercise is the reflective component of OC703 (eg at high grazing angles). many think that OC703 will absorb regardless, but the ETC will detail you if you are getting reflections off of your rigid fiberglass! is that the source in the case of the above chart @ 6-8ms?
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post #73 of 292 Old 09-28-2011, 11:09 AM
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also, looking at this measurement:



you need to zoom in for more resolution - is there any edge diffraction off of a device at 1-3ms or so? (can't tell when zoomed out this far)? it's likely it could be the floor. if so, you'll notice that the carpet doesn't stop it - because carpet absorbs HF content but not lower specular energy, where the bulk of the energy is to begin with. this is why it's somewhat comical when people recommend rugs...as the rugs generally arent acceptable absorbers of the lower specular energy where the bulk of the gain is.

there is a termination (in red), but it is not reinforced by a loud, diffused decaying sound field. it's a specular reflection within the decay that is much, MUCH lower in gain - which may sound dead to you.

what is that specular reflection (in red)? do the string test and find out what boundary it is off of.

also, you now have responses from each of the listening positions. and they are all slightly different. you can hunt down where certain energy is being reflected from and attenuate it - and as each listening position starts to have the same looking ETCs, then you will have a more consistent response across that row.


also, see the spikes in blue? trace that out and find out what's going on. remember, the ETC details how the specular energy is behaving within the room with respect to the listening position. since this is the center speaker - is there energy bouncing back and forth from the front of the room to the rear, until it is entirely damped?
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post #74 of 292 Old 09-28-2011, 12:26 PM - Thread Starter
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localhost127;
Thx for replies and bandwidth - really, I'm starting to grasp ETC and it's role/positioning as a acoustic tool, some detective/experimental work for this weekend.

btw, I'll suggest to the author of REW (John), besides ms on the horizontal axis to overlay distance, as that is in the end what we need to correlate to, one above and one below the axis line.
No need to whip out the calculator every time to say "sound from speakers travels 1,125ft in one second, and I have this spike at 7ms I need to hunt down, so that's 1,125/1000*7= 7.875 feet dist traveled", when it can be plotted for you to easily use.
(heck, I donated $ to him because I use the software and see it's value, so feedback from me as a paying customer should count for something)


[edit]
done http://www.hometheatershack.com/foru...same-axis.html
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post #75 of 292 Old 09-28-2011, 12:42 PM
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Quote:
Originally Posted by mtbdudex View Post

localhost127;
Thx for replies and bandwidth - really, I'm starting to grasp ETC and it's role/positioning as a acoustic tool, some detective/experimental work for this weekend.

yes!

Quote:
Originally Posted by mtbdudex View Post

btw, I'll suggest to the author of REW (John), besides ms on the horizontal axis to overlay distance, as that is in the end what we need to correlate to, one above and one below the axis line.
No need to whip out the calculator every time to say "sound from speakers travels 1,125ft in one second, and I have this spike at 7ms I need to hunt down, so that's 1,125/1000*7= 7.875 feet dist traveled", when it can be plotted for you to easily use.
(heck, I donated $ to him because I use the software and see it's value, so feedback from me as a paying customer should count for something)

it already does that i believe! i forget off the top of my head - but it will give you distance on the graph. keyboard shortcut IIRC (ill verify when i get home).
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post #76 of 292 Old 09-28-2011, 03:33 PM - Thread Starter
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Quote:
Originally Posted by JohnM View Post

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.
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post #77 of 292 Old 09-28-2011, 03:42 PM
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Quote:
Originally Posted by mtbdudex View Post

Response from John.

cool - just make sure you are measuring total time of flight (so, the delta between the reflection and original signal PLUS the distance from the speaker to the original signal) = total flight path for a particular reflection.

have fun!!
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post #78 of 292 Old 09-29-2011, 07:40 PM
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Quote:
Originally Posted by mtbdudex View Post

So, -20db is "better" than 10-15db softer than the initial direct sound.
Check.


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.
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post #79 of 292 Old 09-30-2011, 07:43 AM
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Hey MTB,

Great work!.

Not sure if you have seen this but this little app gives you distance as well as ms.

http://www.youtube.com/watch?v=2m4Sv7JiVLk

You need an Iphone or ipad though...

Test,

Mpray1983- "User error due to sneeze or fart occurred during measurement"
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post #80 of 292 Old 09-30-2011, 07:46 AM - Thread Starter
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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.

Got it, this chart was made in 1990 by Mr Toole, I may have seen it before in my various readings, or from his book I have "Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms".

So, I'm mostly "good" in that viewpoint, other homework still.
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post #81 of 292 Old 09-30-2011, 07:58 AM - Thread Starter
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Quote:
Originally Posted by test4echo101 View Post

Hey MTB,

Great work!.

Not sure if you have seen this but this little app gives you distance as well as ms.

http://www.youtube.com/watch?v=2m4Sv7JiVLk

You need an Iphone or ipad though...

Test,

I've got iPhone4(Feb-2011) AND iPad2 (at home), will try it out, thx!
[edit - Well, of course not free $20 + more for ETC module, as I have REW will stick with that for now, if I was an acoustician for a living I'd get this as tool set http://www.studiosixdigital.com/etc_...ime_curve.html]

How did I live for 5 years prior to my iPhone 4 w/o data plan I don't know.
From this -yea it had stick antenna................................to this:
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post #82 of 292 Old 09-30-2011, 11:28 AM
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Hey Mike,

Rats...I didn't realize the app wasn't free. Oh well.
Not sure how accurate it would be anyway.
Better off with REW.

I gotta say, it took me some time but I'm really starting to understand ETC and am getting pretty excited to start some measurements myself.
I didn't realize at first the implications of this thread.

I would love to see you try to pinpoint at least one early reflection using the string method though!
It would great to put a face to an early reflection (so to speak).

Keep up the great work!

You too localhost127! Just a pleasure to read. I love the fact you DO include SAC's advice. He participated in one my threads and I found him just amazing to read.

BTW Mike, whats wrong with a stick Antenna?
This is what I STILL use!



No need to feel sorry for me (unless you want to)

Test,

Mpray1983- "User error due to sneeze or fart occurred during measurement"
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post #83 of 292 Old 09-30-2011, 11:36 AM
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Originally Posted by test4echo101 View Post

You too localhost127! Just a pleasure to read. I love the fact you DO include SAC's advice. He participated in one my threads and I found him just amazing to read.

ha! i have so much bookmarked from him from ages ago when you would read it and just go "uhhh, ok..." and move on. now i go back and re-read and didn't have the comprehension back then that he's essentially handing everything to you on a silver platter - and was so blunt about it (in a good way) that most people didnt even realize the significance. funny how that works!

regarding the "mirror-trick" and how everyone assumes it is "the right and only way to do things" ... this comment made me chuckle:

Quote:
Originally Posted by sac View Post

assuming one even uses any - such as the infamous mirror technique that was initially introduced as an explanation of concept, not as a definitive treatment protocol!

...

As I mentioned, the mirror is a illustration of concept that was first presented to help folks visualize ray performance. It is capable of only indicating some of potential pathways - it provides no information as to which pathways are important (as in "detrimental"), and it provides no information as to indirect diffractive sources.

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post #84 of 292 Old 09-30-2011, 11:40 AM - Thread Starter
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Originally Posted by test4echo101 View Post

BTW Mike, whats wrong with a stick Antenna?
This is what I STILL use!


No need to feel sorry for me (unless you want to)

Test,

Ha, I'd still be using that phone, it was plug in to sync, not even OTA sync, but after 1,000's of plug/unplug the connector went DOA in Jan-2011 and I could not charge/use it.
That is ONLY reason I have iPhone4, as I was really waiting for IP5 for 4G network.
Heck, manual sync was good enough, I saw all my work outlook calendar and contacts, no email was ok.
It was a mobile tool that "worked", now, I'll keep this IP4 until IP6 is out, skipping IP5.
peace.

Oh, Go Detroit Tigers in the baseball playoffs!!
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post #85 of 292 Old 09-30-2011, 11:54 AM
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Quote:
Originally Posted by localhost127 View Post

ha! i have so much bookmarked from him from ages ago when you would read it and just go "uhhh, ok..." and move on. now i go back and re-read and didn't have the comprehension back then that he's essentially handing everything to you on a silver platter - and was so blunt about it (in a good way) that most people didnt even realize the significance. funny how that works!

regarding the "mirror-trick" and how everyone assumes it is "the right and only way to do things" ... this comment made me chuckle:

Yep...that is exactly my experience with him as well. He puts more info in one paragraph than most people post in a month. Unlike some others, all his info seems to be spot on.
If you skip even one sentence, you miss something significant.
Glad he's chiming in over at HTF.

He's gotta be old...He knows too much.

Test,

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post #86 of 292 Old 09-30-2011, 11:56 AM
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Oh, Go Detroit Tigers in the baseball playoffs!!

Ha! You know it! Can't wait to bring those damn Yankees down!
However, I think YOU should be focused on measurements, not baseball right now. I'll text you the score....lol


Test,

Mpray1983- "User error due to sneeze or fart occurred during measurement"
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post #87 of 292 Old 09-30-2011, 02:50 PM
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Originally Posted by test4echo101 View Post

Glad he's chiming in over at HTF.

He's gotta be old...He knows too much.

Yeah, I'd imagine he is, shall we say, "senior" since he was involved in all those early LEDE and RFZ workshops. And one can only imagine he was well advanced in acoustics and probably out of college (for who knows which time) by then.

I think MTB mentioned HTshack deleting "mas"... my understanding is that was the same person as SAC. And I have the same problem on GS except that I don't think he got booted. I think his habit was to go back and delete lots of his old posts, who knows why (I'm talking about the ones the mods didn't delete for being argumentative, heh). Maybe it was the same thing on HTshack. Tthere have been several times I wished I could have seen the entire post based upon people's quoted sections in replies. He did tend to be long-winded, not like I should complain about that heh, but I actually usually "got" his sense of humor and definitely have also gotten large amounts from his posts.
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post #88 of 292 Old 09-30-2011, 05:10 PM
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PM him. he's more than happy to have 5hour conversations on the phone with you

mentally exhausting...but more learned in a day than the past year.

incredible.
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post #89 of 292 Old 09-30-2011, 06:06 PM
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PM him. he's more than happy to have 5hour conversations on the phone with you

mentally exhausting...but more learned in a day than the past year.

incredible.


All I can say is YUUUUUUUUUP!...

Test,

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post #90 of 292 Old 10-02-2011, 01:23 PM
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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,

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