Acoustical Measurement Software

[saurabh]

"ETF runs in all 32 bit Windows operating systems. ETF is a post processing application and computer size/speed is irrelevant to its operation. To ensure efficient operation, a user should have 64 MB of memory and 400 MHz of processing speed.

ETF was designed for room acoustics and small medium sized rooms. It is ideally suited to home theater installations and where high quality playback is required.

The basic ETF package includes all of the capabilities of conventional acoustic analyzers. The basic package includes impulse response, unfiltered frequency response, 1/2,...,1/12 fractional octave measurements, 1/3 Oct RT/60, 3D graphical representations of spectral decay, band filtered energy time curves, microphone speaker distance (automatic) and phase measurements. All measurements are gated meaning that room reflections can be removed from the measurements and pseudo anechoic measurements can be taken. "

http://www.acoustisoft.com/index.html

I could not locate the Test Tone CD as mentioned in their help file but an alternative file can be downloaded at http://www.realtraps.com/test-cd.htm which you can burn.

Measures from your PC/ Laptop , seems interesting, I will give it a try !!!.

[Snap]

Have you checked out SMAART Live? That is a pretty sweet program. That is what I use for Pro sttuff and home.

Let us know what the ETF does for you.

[ThomasW]

Actually the original ETF audio file contained a shaped white noise burst in keeping with the fact that it's taking MLS readings. Using sine wave test tones doesn't work with MLS software.

I'll look around I probably have a copy of it somewhere. You'd need broadband connection and a big mailbox to get it.

[saurabh]

Its too bad, I cant run it from my laptop cos of the Line-IN/OUT constraint. I spoke to them and they advised me to go for a USB sound card. Also the test tone file is no longer available for download and they will have to ship the CD at my cost and above all test tone method is not advisable by them for correct results. Hmmmm.......too bad

[BlazeMaster]

is there any other affordable software out there that'll help you graph your in room results to determine what type of acoustic treatments you need?

[Snap]

I don't know of any Blaze. If there is one out there that is cheep that makes graphs I want to see it! my RTA just shows the freqs and a bunch of other info.

[BlazeMaster]

figures, i'm sure that if it does exist, I'd probably have heard of it and used it by now.

[ThomasW]

You can model the acoustical properities of the room with CARA or RPG Acoustics Room Optimizer

[BlazeMaster]

but are they affordable and easy to understand for someone like me who has a vague understanding of room acoustics?

[scient]

Calibration software?

Is this the same as calibration software?

I was to be able to use software on my PC, have it play test tones and feed the output from the speakers back to the PC so that it can analyze the room acoustics and the frequency reponse of my system so that I can tune it.

Do the softwares that you mention do this or should I be looking for something else?

[eddiem67]

I would say yes, the software will give the graph of your set up based on you room and speaker placement. Simple movement of speakers can help flatten out your response using the graph. If you dont have a laptop, you can always just buy Audio Controls RTA unit.

[AndrewM]

but are they affordable and easy to understand for someone like me who has a vague understanding of room acoustics?

I have CARA and have used it in a couple of rooms with good results, it's an affordable product (granted that's always relative). Past that it isn't simple and easy to use, nor is it grossly complex either. Essentially you program your room into the software, including every detail, it will turn it into a 3d model. Then you program in your equipment (speakers essentially), and then you can analyze what the sound will do in the room.

There is no measurement ability in the software, so everything will be based off what you program into it (so the more accurate the better). The power comes in because you can analyze all sorts of thing, you can program in a "zone" where your speakers can be placed, and during the analyzing the program will look at every possible placement (within that "zone") and show results based on the best, you can do the same for listening position. It's also a great way to take the "hard" part out of doing room treatments, as you can analyze what various treatments will do in various spots in the room.

Andrew

[ThomasW]

If you dont have a laptop, you can always just buy Audio Controls RTA unit.

I have an Audio Control SA3051 Real Time Spectrum Analyzer and it's fundamentally a useless product for anything other than measuring SPL.

1/3rd octave RTA's don't provide fine enough incriments to be very useful.

And for what it cost $1000.00, one could buy Praxis.

[eddiem67]

I was actually talking about the IASYS unit, but might actually cost more than a laptop and software package.

http://www.audiocontrolindustrial.com/product.asp?Product_Id=19940&d_id=5650&l1=5650&l2=

[csuzor]

I have tried the software from http://www.acoustisoft.com/ (thanks for the link)
and I get some fancy results, including frequency spectral decay plots, and frequency response curves, and impulse response curves, etc.



It is fairly easy to use:
plug the line out from PC into one of the multi-inputs on preamp
plug a microphone into PC microphone in
calibrate the microphone
run the normal and low frequency tests
view results

I have a normal PC in the lounge room, so the soundcard is full-duplex. I did not use the left channel for response validation, because I am using a microphone direct to the PC, and not a microphone amp.

However, I would have preferred a 360deg response microphone, because I had to point the microphone towards the speaker. Taking good measurements will take some practice. The demo version only allows 2 test data, then you have to close the program and restart.

And now that the results are there, what to do with those? That interpretation of results into actions is not easy... Any experts here?

Christophe

[scient]

And now that the results are there, what to do with those? That interpretation of results into actions is not easy... Any experts here?

I agree with you Christophe. Now what?

[Paul H]

... And now that the results are there, what to do with those? That interpretation of results into actions is not easy... Any experts here?

Christophe

What is your underlying reason for taking measurements? Are these for speakers under construction? What types of adjustments are you considering?

I'm sure some of the folks here who can help will jump in, but they'll need this type of information to be able to help.

Paul

[csuzor]

What is your underlying reason for taking measurements? Are these for speakers under construction? What types of adjustments are you considering?

I'm sure some of the folks here who can help will jump in, but they'll need this type of information to be able to help.

Paul

Thanks Paul,

if I spend the time to get accurate measurements, it looks like it will show some room reverberation modes at specific frequencies. To fix this, I guess either adjusting room acoustics (how?) or using a graphic equaliser (costly?) could help...

For the moment, I don't have a sub, but this is an upcoming purchase... there are models with digital room correction... can this software help me decide if I will need correction?

Finally, to correctly position 5 speakers, I imagine there are a bunch of acoustic factors to consider... can such software help?

[saurabh]

Well you have to read the help files and example setup on their website, you will get some idea on how to decipher the measurements. I did that but unfortunately, I work solely out of my Laptop, which this software does not recommend. You will also have to take measurements from two-three different setups to compare which one is the best placement option. I thing they have a good help on the website for this, go through it. Atleast I was able to follow most of it while reading it........too bad cant put it to practice.