Room too dead???

Post and discuss acoustic topics, Studio design, construction, and soundproofing here

Postby cadesignr » Tue Jul 05, 2005 3:57 pm

I am curious. With all the ASTM standards for everything under the sun, why is it that the ONLY advice I hear for evaluating ones room  is usually......listen to your favorite CD's.  How does that REALLY define what is happening, as everyone has their own opinion, which makes all of this stuff subjective. Even with EFT(ETF?) what is used for the sound that tells you ...IT SOUNDS GOOD AS PER STANDARD????? ,  and,how would one truely say....YEA, there it is!!! PERFECT!!

Maybe there should be an ASTM or some other standard AND reference recording or test recording  for evaluating control room:
A. Speaker position
B. Engineering Position
.C.  Decay at set frequency bands
D.  Diffusion(maybe?)
E.  More?
F.  Less?
G.  None...ie....it is impossible


 Maybe there should also be ASTM Standard to read before posting  suggestions like mine
  :bang  :D (sorry if mine makes no sense....ie...ASTM STANDARD 6943. 1 Reference suggestion by forum member shall be only submitted upon full understanding of said relational advice to problem.  Options.
 Shut up
 Reread standard
 Evaluate suggestion prior to posting.
 Grow thicker skin post suggestion
 Take up new hobby
   :oops:  :mrgreen:
fitZ
cadesignr
 

Postby bert stoltenborg » Tue Jul 05, 2005 4:10 pm

Lets also make standards for musical instruments.
Every guitar should be like a stratocaster but with a PAF-humbucker in bridge position, every amp like a marshall 2104, etc etc.
Lets make the world one big standard, like the soviets tried. That will make life soooo exiting....

(Paul and Ido probably would like a standarisation for women, and Eric one for cables)

:mrgreen:  :mrgreen:
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Postby J.F.Oros » Tue Jul 05, 2005 4:10 pm

bert stoltenborg wrote:Hey Eric,

We're OT-ing again.

Lets start a band: the OT-twins.

Do you need a bass player  :D  (the OT-trio) ?

And to keep the OT: Bert, if you decide to go "public" with your anti-politicians&stuff attitude (well, more public then here anyway) you kould have a cool domain name :

www.stoltemb.org

(you just have to find what "stoltemb" means  :( )

:mrgreen:
Last edited by J.F.Oros on Tue Jul 05, 2005 4:16 pm, edited 1 time in total.
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Postby bert stoltenborg » Tue Jul 05, 2005 4:13 pm

Goddam it, what is it that nobodies seems to be able to spell my name right?

:mrgreen:
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Postby bert stoltenborg » Tue Jul 05, 2005 4:15 pm

Hey Flaviu,

can you also sing?

Eric as singer-drummer (every Belg can sing from birth), and we on background vocals.
Eric probably wants to be the loudest anyway....    :twisted:  :twisted:
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Postby Paul Woodlock » Tue Jul 05, 2005 4:18 pm

bert stoltenborg wrote:Lets also make standards for musical instruments.
Every guitar should be like a stratocaster but with a PAF-humbucker in bridge position, every amp like a marshall 2104, etc etc.
Lets make the world one big standard, like the soviets tried. That will make life soooo exiting....

(Paul and Ido probably would like a standarisation for women, and Eric one for cables)

:mrgreen:  :mrgreen:


No chance! :)

Women come in all flavours and that's how it should STAY.  :P

On a wider note.. Advertising tries to encourage people to conform to some politically correct and boring 'standard'. Most people, being sheep conform.
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Postby J.F.Oros » Tue Jul 05, 2005 4:21 pm

Hey Flaviu,

can you also sing?

Eric as singer-drummer (every Belg can sing from birth), and we on background vocals.
Eric probably wants to be the loudest anyway....      

I think we should go for instrumental.
And if we will play jazz, will have to learn a lot of standards, but having Eric we are covered on that  :D
Last edited by J.F.Oros on Tue Jul 05, 2005 4:32 pm, edited 1 time in total.
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Postby bert stoltenborg » Tue Jul 05, 2005 4:29 pm

:D

I always wanted to be a fusion guy!

:lol:
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Postby J.F.Oros » Tue Jul 05, 2005 4:40 pm

bert stoltenborg wrote::D

I always wanted to be a fusion guy!

:lol:

Me too, but fusion with the wrong person (even if SHE looks really good) can be verry unpleasant sometimes  :bang
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Postby Eric.Desart » Tue Jul 05, 2005 4:40 pm

bert stoltenb[size=150]o[/size]rg wrote: (Paul and Ido probably would like a standarisation for women, and Eric one for cables)
:mrgreen:  :mrgreen:

bert stoltenb[size=150]o[/size]rg wrote: Eric probably wants to be the loudest anyway....    :twisted:  :twisted:

bert stoltenb[size=150]o[/size]rg wrote: StoltenbOrg, please.

bert stoltenb[size=150]o[/size]rg wrote: Goddam it, what is it that nobodies seems to be able to spell my name right? :mrgreen:

:twisted:  Stoltenburg:  one of the VERY CLEVER things politicians do is NOT showing their ACHILLES TENDON
Image
divinely-inspired
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Postby J.F.Oros » Tue Jul 05, 2005 4:57 pm

Eric, you just named the first album we would release with our new band:

ACHILLES TENDON

How cool is that ?!  :8
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Postby avare » Tue Jul 05, 2005 6:33 pm

why is it that the ONLY advice I hear for evaluating ones room  is usually......listen to your favorite CD's.  


I don't understand you.  You have been on several forums and have read about the recommended practices from (in no order):

AES
CCITT
EBU
NARAS
Tonmeister SSF

EAch one details physical and measurable cdriteria.  Numerous people have posted that professionals test an dfine tune the rooms....


Andre
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Postby cadesignr » Tue Jul 05, 2005 7:58 pm

Lets also make standards for musical instruments.

They do. It's called TUNING(440=A)! :evil:  DUH!!  ie....

   "Can someone make sense of my instrument. I TUNED IT MY WAY..but I can't seem to play with other musicians..." :roll:

ALL studios have different equipment that STILL MEET STANDARDS. Same with insturments. but you  must  tune them TO THE STANDARDS!

Lets make the world one big standard, like the soviets tried. That will make life soooo exiting....


I don't live in europe,  so I wouldn't know, however
your attempt at  sarcasm is only matched by your european condencending manner and arrogance, OF WHICH there is a standard you hardly meet.   It is duly noted Bert.

I don't understand you.  You have been on several forums and have read about the recommended practices from (in no order):

AES
CCITT
EBU
NARAS
Tonmeister SSF


  I don't understand  you either andre. IF SO< then WHAT the SPAMMER is the problem with this thread.  If  there ARE a set of standards set forth in these PROFESSIONAL org's, then why not link him to those that are relevant?  .....hell, if all of us were PRO AE's or acousticians..what the hell would we be here for.  I mean,  even if you met the criteria(which "I" personally did NOT KNOW EXISTED except for outdated LEDE as quoted in Alton Everest Handbook),  how does one KNOW you have met them, which seems  is EXACTLY   what this thread is ABOUT, no? 8O

Numerous people have posted that professionals test an dfine tune the rooms....


 Well there you have it  from the horses mouth Tasman. Of course, seeing as there are already "standards", in place I guess, accordign to andre,  these so called pro standards must  render the previous replys such as these......


Everything closes in and gets claustrophobic. In a way, it is like wearing permanent ear plugs. Acoustic perspective goes. You feel physically detached from what you are hearing and above all, it gets extremely tiring very very quickly. You'll soon know when it is too dead because you simply wont be able to listen for very long. When balancing my room, I found you can go a long way before it gets too dead but there is a fine and narrow line between deadness and being comfortable. Being a narrow line, I found it quite easy to identify when I hit it. Sit down and listen for 30 minutes. If you get any fatigue that might be described as acoustic numbness, you've hit that line. My room and Paul's are massively damped (far more than some people recommended) yet are not tiring at all so if you have just done bass traps, I doubt you are there yet. Above all, use your ears....


and...

from Morfey's Dictionary of Acoustics
Dead room: a room in which the total absorbing area approaches the actual room surface area. Note that such a room cannot qualify as 'live'; compare live room.
Live room: A room in which the amount of sound absorbtion is small enough that the mean free path Lav is greater than square-root(a), where 'a' is the room absorbtion.


and....

If the bass varies wildly all around the room then there isn't enough standing wave absorption ( bass traps ) IMO.




[size=18.....]fucking USELESS...[/size]......  
Although, this one tells me something...
In a small room (with lots of treatment) you cannot derive real reverberation, only direct sound and hard reflections. Reverb is absorbed so much that is not measurable.


Thanks andre. I will remember this.
fitZ
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Postby Bob » Tue Jul 05, 2005 8:03 pm

bert stoltenborg and cadesignr:

RT is a statistical phenomenon.
A soundfield in a room is built from direct sound, directed reflections and statistical stochaic reflection (reverb).
In a small room (with lots of treatment) you cannot derive real reverberation, only direct sound and hard reflections. Reverb is absorbed so much that is not measurable.
A target RT in such a room is just a (rather crude) way to calculate the amount of treatment needed, (for what that's worth).


RT60 is also not well defined for small rooms with little-to-no absorbtion. See Critical Distance by Scott far below.
However, the original definition of RT60 by Sabine was somewhat because of the tools of the day. Today's tools can measure much shorter intervals of time and extrapolate.

cadesignr: nevertheless RT60 can still be used. Some acousticians use it all the time, and others do not.
From the studiotips acoustic faq
Knowing a room’s volume and its Sabin content it is possible to estimate many of a room's basic acoustic properties including the strength of its reverberent field. This estimate is generally expressed as a room’s RT60 which is short hand for the time in seconds that a sound will take to decay to 60 dB below its initial impulse energy level. A high RT60 means that sound will bounce around for a long time before it is absorbed. Dead rooms have low RT60’s. Keep in mind that only large rooms can have a "real" RT60 - medium and small rooms can't support a random field of reverberations - they are just to small. Nonetheless, these calculations can help one estimate how much absorptive treatment will be needed to tame the "boom" in any given proposed room.
Estimates of this sort are helpful in the design process for many purposes, but the main purpose you should concern yourself with working with these numbers is that of estimating how much absorptive treatment a room will need. Smaller rooms cannot tolerate high RT60’s (long reverb times) without introducing strong colorations to the low frequency part of the reverberant field. Even large rooms will need to limit reverb times in order to be considered good sounding rooms for various purposes. Generally, for a tracking/recording room, the lower the low frequency energy expected, and the larger the room, the higher the RT60 can/should be.


I use the above, via formulas from the Sabine Equasion and ITU rather than text/english, on my http://www.bobgolds.com/Mode/RoomModes.htm

Maybe we should change the name of this beast; it seems after some years it still causes confusions.
I used to call it "Theoretical RT60" for almost a year because of postings at Yahoo Acoustics, until Terry Montlick (an experienced accreditted and professional acoustician who hangs out at AVSFORUM) wrote that he uses RT60.

Yahoo! Groups : acoustics Messages : Message 147 of 11509Yahoo!   My
     
           From:  SRF7@xxx.xxx
           Date:  Tue Nov 23, 1999  6:09 am
           Subject:  Re: new article



           In a message dated 11/20/99 9:18:46 AM Eastern Standard Time,
           tford@j... writes:

           > >address. Several people have refered to RT60, reverberation time
           > >in a acoustically small room does not exist. By definition the
           RT60
           > >is a statistical measurement that is made at some point beyond
the
           > >critical distance. The "critical distance" is the point in a room
           that
           > >the level of the reflected sound is equal to the direct sound. In
           a
           > >acoustically small room the critical distance does not exist.
           > >
           > >Greg

           > Hi Greg,

           > How does that work? I would think that if the room were small and
           > reflective enough that the reflected sound could easily be almost
           as large
           > as the direct sound (minus standard reflective losses). It would
           sound like
           > your typical bathroom. Not an ideal recording or monitoring
           environment, but
           > certainly possible. What am I missing?

           > Regards,

           > Ty Ford

           Best I recall...

           Sound encounters uncompressed (and unexpanded) air and uses energy
           to conform
           the static (or at least incoherent) medium (air at rest, or at least
           not
           conforming to the waveform) into a transferring medium (vibrating
air
           conforming to the waveform) as the wave travels (by virtue of
           creating
           coherent conformance in the air mass to the waveform). Sound waves
           propagate
           in 3 dimensions and therefore the energy necessary to propagate a
           given
           amplitude wave rises to the 3rd power per unit of linear distance
           from the
           sound source (or more rationally sound diminishes in power at the
           rate of the
           inverse of the cube root of distance from the source ... that is to
           say
           really fast). The foregoing notwithstanding, its not that simple,
the
           waveform encounters an additional impediment in that air gets warmer
           even
           while transferring the wave (air is not a frictionless medium) and
           thus
           absorbs some of the energy as heat. Suffice to say, it takes a lot
           more
           power to make a given level of noise 10' feet away than it does 1'
           away, and
           the change in requisite power exceeds the cube of the increase in
           linear
           distance.

           For this reason, even given Sabin numbers of zero (perfect
           reflection) for
           the walls, sound power is dropping off at an enormous rate for
           reflected
           sounds because such sounds are of course twice the distance to the
           wall
           further away (past your head to the wall and then back) from you
           than the
           sound source itself. Throw in a Sabin number for the wall and a bit
           of
           humidity in the air and its gets worse ... at least as far as the
           propagation
           of the sound is concerned.

           Thus, you have to get a good distance away from the source for the
           sound
           (called critical distance, the calculation of which is a matter of
           room
           volume, but is altered by the frictional quality of air and the
           overall Sabin
           content of the room) before there is any possibility of the
perceived
           amplitude of the reflected sound equaling the perceived amplitude of
           the
           source.

           In a small you room this never happens (the critical distance does
           not exist)
           for the simple reason that you can't get far enough away from the
           sound
           source for the reflected signal to reach parity in amplitude. Thus
           you can't
           measure the time to reach a 60 dB drop from initial amplitude at the
           critical
           distance because there is nowhere to stand to take the measurement
           (no
           critical distance).

           Its late... I hope this makes sense ... email me if it doesn't and
           I'll try
           again.

           Scott R. Foster


------------------------

The terminology "RT60" has a very specific technical meaning that
was originally derived by Sabin. It was further refined by Fitzroy
which takes into account rooms that have different absorption
coefficients on different surfaces. The key here is that the sound
must be well mixed in a way that the angle on incidence on the
reflecting surfaces is statistically random. Inject a steady state
sound, like pink noise, into a room. If you are beyond the critical
distance you can wander around with a sound level meter and the
sound pressure will not change significantly. The ability of a
material to absorb sound is quantified with a value called the
"absorption coefficient" and is statistically based. It is really the
average absorption coefficient since the amount of energy absorbed
by any material depends on the angle of incidence of the wave.
In a acoustically small room the angle of incidence is not random
and any attempt to calculate RT60 will be futile. Any attempt to
measure it will depend on where you are in the room and will
yield wildly varying results. In a small room we are dealing
with modes, Don Davis calls the decay "Modal Decay Rate",
which is a technically more accurate description.

Greg

--------------------------

I would like to add that although RT60 is a useless measurement in small
room acoustics, doing the reverberation calculations for rt60 is useful in
determining a rough amount of absorption materials needed to treat the
room. The calculations will also help determine at what frequencies more
absorption is needed. Which would be dictated by the frequency that has the
greatest amount of absorption in the room. The selection of absorption
materials is then based upon what is needed to have roughly equal
absorption at all frequencies except for maybe a slight rise in the reverb
time in bass frequencies.

Dan Nelson

-------------------------------

======================================

SAME THING SAID AGAIN

Smaller spaces do have an RT60. My usual rule of thumb for RT60 is (based on ideas from Scott, Greg and Dan):

a) doing the reverberation calculations for RT60 is useful in determining a rough amount of absorption materials needed to treat the room (Fitzroy style),

b) RT60 in a small room can not be measured. The sound must be well mixed in a way that the angle of incidence on the reflecting surfaces is statistically random. You have to get a good distance away from the source for the sound, called the critical distance, before there is any possibility of the perceived amplitude of the reflected sound equaling the perceived amplitude of the source. In a small room this never happens (the critical distance does not exist) for the simple reason that you can't get far enough away from the sound source for the reflected signal to reach parity in amplitude. Thus you can't measure the time to reach a 60 dB drop from initial amplitude at the critical distance because there is nowhere to stand to take the measurement (no critical distance). Inject a steady state sound, like pink noise, into a room. If you are beyond the critical distance you can wander around with a sound level meter and the sound pressure will not change significantly. Within the critical distance any attempt to measure it will depend on where you are in the room and will yield wildly varying results. In a small room we are also dealing with modes.

======================

http://www.avsforum.com/avs-vb/showthre ... ost4014340

Terry Montlick Laboratories
Home theater acoustical analysis and certification
www.componentacoustics.com

We measure it all the time, Bob. It's absolutely no different for a small room than a large room. This measure has nothing to do with critical distance, as the direct sound is of no consequence.

The old-fashioned way was to fire an impulse (balloon pop or starter pistol) and measure the decay of the sound. It can and will decay to 60 dB of its initial reverberant energy (NOT the level of the first sound arrival, which is the time-delayed original impulse, and which is irrelevant to the measurement). Paper strip charts recorders used to be the standard way of doing this. Averaged over a number of readings, you get a very good measurement of reverberation time.

We use a more modern technique, of course. We derive the impulse response by deconvolving a stimulus sound of pink noise from its measured recorded sound in the room. This impulse response is then filtered for various frequency bands, and the RT60 for each frequency band measured from the dB slope of the amplitude. Often, we don't have a full 60 dB of dynamic range, but this has nothing to do with the room size. Nevertheless, RT60 can be extrapolated pretty accurately (+/- 5 hundreds of a second) using this method.

Last edited by Bob on Tue Jul 05, 2005 8:25 pm, edited 2 times in total.
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Postby Bob » Tue Jul 05, 2005 8:21 pm

Some more stuff
RT60 opinions

I have never found RTs to be very useful for small room design.
Reasons:

1. Small rooms are only diffuse at very high frequencies.

2. The difference between 0.20 seconds and 0.30 seconds at 250 Hz in a
bedroom or project studio - while it is a 50% "jump" in RT - doesn't tell
you much of anything. I would venture to guess that many folks wouldn't even
hear much difference. (Put into relative terms, a large room going from 1.50
seconds to 2.25 seconds - same percentage "jump" - is much more of an issue.
In the mid and high bands, this could detrimentally affect intelligibility.)

3. Whether you use Sabine or Fitzroy won't make much difference. Fitzroy
might give you closer predictions to what the untreated room would actually
be. (His paper seems to suggest as much, though I have found plenty of cases
that don't "fit.") But to that I would say, "So what?" Take an example:

15'x12'x8' room; gypsum board walls & ceiling; carpet floor.
Sabine RTs (500 Hz, 1 kHz, 2 kHz) = 1.23 sec, 0.90 sec, 0.51 sec
Fitzroy RTs (500 Hz, 1 kHz, 2 kHz) = 1.30 sec, 1.46 sec, 0.74 sec

Treated model:
With 225 square feet of 3" acoustic foam, Sabine RTs (500 Hz, 1 kHz, 2 kHz):
0.25 sec, 0.23 sec, 0.20 sec
(This is about 36% coverage of walls and ceiling.

With 170 square feet of 3" acoustic foam, Fitzroy RTs (500 Hz, 1 kHz, 2
kHz): 0.25 sec, 0.23 sec, 0.19 sec
Note: 120 square feet on the walls, 50 square feet on ceiling. This is about
28% coverage of walls and ceiling.

(End of example)

4. In small rooms early reflections are the key. Absorb them well - and
there are plenty of "primers," as well as people here, that can help with
the "how to" - and you will never have to worry a lick about RT. The above
example jives with what I tell people every day: I.e., At least 20% to 35%
coverage of walls and ceiling with good acoustical treatment fairly evenly
distributed will go a long way in a small room. For mixing areas, treating
the early reflection points first is key. After that, so on and so forth
into bass and diffusion and the rest as appropriate.

Just so ya know: It's not that I'm "anti-RT." But I am about using the right
tool for the job. To this day, RTs have never helped me in small rooms.
Therefore, I am reluctant to ever start using them.

Best regards,

Jeff D. Szymanski
Chief Acoustical Engineer
Auralex Acoustics, Inc.

PS - Fitzroy is a wonderful tool for those rooms that have one "small"
dimension relative to the other two. E.g., a 100'x90'x10' ballroom. Sabine
won't give you anything close to reality. Fitzroy will be a much better
predictor.

==========================================
Actually, the Sabine RT formula assumes a diffuse sound field. This means
that the room is big enough that the placement of absorption isn't relevant,
just the amount. The Fitzroy equation is better for small rooms because it
takes into account where the absorption is. Imagine a project studio where
all the absorption is on the ceiling & floor - much of the sound is going to
bounce around off the walls before it ever hits the ceiling or floor. Now
picture the same amount of absorption distributed on the walls, ceiling &
floor. It's more likely to suck up some of the sound on the 1st or 2nd
reflection. I'll send you a spreadsheet that we use to calculate both the
Sabine & Fitzroy in octave bands. Of course, the results are only as good as
the inputs, so choosing the right absorption coefficients will make a big
difference. Even then, the calculation won't necessarily match reality, but
it should help give you an idea of what frequencies are giving you problems.

Stephanie Renaud


---------------------
---------------------

First, the document being referred to here can be downloaded from AES at:
http://www.aes.org/technical/documents/AESTD1001.pdf

Second, it might be worth noting that the RT60 recommendations from this document also state tolerances of ±0.05s between 200 and 4000 Hz. These are tolerances for average RT60. In other words, you should - in practice - evaluate the RT60 at no fewer than 4 positions in the room (more if you can) and average the results to determine whether the criteria have been met. One thing spreadsheets won't typically show you is the position dependence of RT60. This makes sense since your predictions are statistical - inherently averaging all locations in the room.

In design, many of you are already aware of my reluctance to use RT60 as a primary predictor for any small room. "Small" being < about 10,000 ft³ (or < about 300 m³). If you approach the room as a discrete reflection challenge, you will typically reduce the RT60 to meet the criteria being discussed here by default.
Best regards,
Jeff D. Szymanski
Chief Acoustical Engineer
Auralex Acoustics, Inc.

-------------------------


Andrew Steel wrote:
My question is what the source is for generating the typical limit lines seen on graphs of reeverb time like those in CARA. The upper limit generally seems to rise at low frequency and the lower limit seems to slope down at high frequency. I know there must be variations based on room volume, application etc and that they are empirically derived. I expected tables or formulae with 'ranges' like those for room ratios in a book or two.

For sources on the ranges, if I'm not mistaken, they have simply been derived over the years through subjective studies. Comparisons of the studies versus what is measured versus what is predicted give us the upper and lower limits we use today. Anyone else know more/different?

For ranges of RT60 that are generally acceptable for different types of rooms, you can look in almost any acoustics text. Beranek and Harris come to mind immediately.
Andrew Steel wrote:
Jeff,
I am also very interested in the position dependance of reverb if you have any good references?

Well, it just is. I mean, RT60s are statistical values. By measuring them, we have removed some of the statistical nature of the quantity.

Analogy: Knowing racecars going around a track average 210 mph doesn't tell you who won the race. And vice versa: Knowing the top speed was 215 mph doesn't tell you the average speed of, say, 33 cars. (Got Indy 500 on the brain, folks! It's May: You can't get away from it in this town!)

RT60s do not take into account any of the idiosyncracies of different positions in the room. The predicted values are taking the general characteristics of the room - volume and surface areas of different materials - and giving you a single value (for the frequency of interest - which by itself is a "big picture" since you're usually looking at octave bands and not discrete frequencies). An average, if you will. There is nowhere in a room you'll be able to measure that value since the formula used to predict RT60s eliminates the position dependence via statistics. To get an idea of whether your predictions are close to what's actually happening, you need to take multiple measurements.

Example: Measure the RT60s behind a couch and see what you get versus placing a mic in the middle of the room, away from any furniture. The position relative to a large absorber like a couch will skew your data. In the prediction, you have simply included "couch" as a line item with some number of Sabins added to the room. This reduces the average. However, if the couch is clear across the room relative to where you are, the RT60s might not seem/measure all that low.

For a complete treatment on RT60 and how we've gotten to where we are, you might look up the Collected Papers on Acoustics by Wallace Clement Sabine. Copies are available through the http://asa.aip.org/ .

Best regards,
Jeff D. Szymanski
Chief Acoustical Engineer
Auralex Acoustics, Inc.
Regards
Bob Golds
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Postby Eric.Desart » Tue Jul 05, 2005 8:57 pm

cadesignr wrote:
Lets also make standards for musical instruments.


Lets make the world one big standard, like the soviets tried. That will make life soooo exiting....


I don't live in europe,  so I wouldn't know, however
your attempt at  sarcasm is only matched by your european condencending manner and arrogance, OF WHICH there is a standard you hardly meet.   It is duly noted Bert.


fitz i very explicit hint you to control your unnecessary aggressive tone.
this is no fun anymore but your uncontrolled frustration.

you want exact general answers and formulas where there aren't.

bert is NEVER, I repeat NEVER been mean to anyone.
you find too easy arguments to justify your agression.  your reply is plain mean and immature.
bert is not europe, keep your political ignorance and simplicity out of this forum, which tells about you, not europe.

andre refers to other threads and sources, which in itself shows the question marks.

bob, now as usual/often provides an enormous amount of usefull data, but also their you will find questionmarks.

if that frustrates you then knock your head against a wall, not against other members.
this isn't the first time.
i will not hesitate to use my function here.
think twice before you reply to this.
Last edited by Eric.Desart on Tue Jul 05, 2005 10:04 pm, edited 2 times in total.
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Postby Bob » Tue Jul 05, 2005 9:36 pm

avare:

why is it that the ONLY advice I hear for evaluating ones room  is usually......listen to your favorite CD's.  

... the recommended practices from (in no order):
- AES
- CCITT
- EBU
- NARAS
- Tonmeister SSF
Each one details physical and measurable cdriteria.


Is there anything in there that would be applicable to my thread here: DIY measurements - what do experts want to see ?
And if so, any URLs that I could read?
Regards
Bob Golds
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Postby avare » Tue Jul 05, 2005 9:48 pm

WHAT the SPAMMER is the problem with this thread.  If  there ARE a set of standards set forth in these PROFESSIONAL org's, then why not link him to those that are relevant?  .....hell, if all of us were PRO AE's or acousticians..what the hell would we be here for.  I mean,  even if you met the criteria(which "I" personally did NOT KNOW EXISTED except for outdated LEDE as quoted in Alton Everest Handbook),  how does one KNOW you have met them, which seems  is EXACTLY   what this thread is ABOUT, no?


Youir language is innappropriate.  

These recomemndations are not normally mentioned because threads like this usually involve a listneing facility already built and the writers often balk at even spending the money for a cheap Behringer type measurment microphone, much less SMAART etc.

As far as links goes, here is three.  There are more of the referenced documents on the internet but this will get you started.

AES
http://www.aes.org/technical/documents/AESTD1001.pdf
NARAS
http://www.grammy.com/pe_wing/5_1_Rec.pdf
Tonmeister SSF
http://www.denhaag.org/~aestusec/students110th/docs/surround.pdf

The bibliographies in the documents direct you to additional recommendations.

Please stop the belligerent swearing.

Andre

edit:  put words into english.  It hopefully did not affect the meaning.
Last edited by avare on Wed Jul 06, 2005 12:17 am, edited 1 time in total.
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Postby avare » Tue Jul 05, 2005 9:52 pm

Bob wrote:avare:

why is it that the ONLY advice I hear for evaluating ones room  is usually......listen to your favorite CD's.  

... the recommended practices from (in no order):
- AES
- CCITT
- EBU
- NARAS
- Tonmeister SSF
Each one details physical and measurable cdriteria.


Is there anything in there that would be applicable to my thread here: DIY measurements - what do experts want to see ?
And if so, any URLs that I could read?


I'm not certain off hand.  I linked some docs in the previous post, and I will re read the docs bearing in mind your thread.

edit: The AES gives the summary in technical terms of room acoustics and perfomance.  I made an error with EBU.  It is the ITU, not EBU.  The ITU docs were on line at the right price a while ago.

Andre
Last edited by avare on Tue Jul 05, 2005 9:57 pm, edited 1 time in total.
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Postby Eric.Desart » Tue Jul 05, 2005 9:55 pm

i can handle the forum.

please stick to content or being the bunch of friends (even when different or disagreeing) we're supposed to be.
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