Hello,
I finally found time to try a little more the REW software that I downloaded 3 months ago, using a ECM8000 + Edirol UA-25. For a "free" download, REW is quite impressive. I wanted to give you some initial feedback. "Vaut mieux tard que jamais" as we said in french.
I started by measuring the frequency response of a small Polk Audio loudspeaker, on a bookshelf, against a wall (The microphone was on a tripod, about 12-15 inch in front of the loudspeaker). The shelf is situated into a fairly small room into my house. I did a comparaison of the result using REW (v4.11) and using the FFT function from that popular "free" software: Audacity. In the latter case, of course, I had to "convert" the result of the FFT into 1/12 octave frequency bands, copying the large text file into Excel...). With Audacity, also, I had to use pink noise as a test signal, instead of a freq log. sweep...
The result?
1-Both curve (REW "smooted" to 1/12 oct, and the curve from Audacity) were very similar (some differences at lower frequencies). So far, so good! A good indication that things seem to work well...The result makes sense anyway for that small loudspeaker on its shelf...
2-REW is (much) easier to use. It's fun too.
3-REW provide a lot of information. For instance the RT-60 (I got 0.2 -0.4 seconds. The room is fairly small and (definitively not empty) filled, so that makes sense - I'll try to calculate it to check).
A few questions:
1- Using Pink noise VS frequency sweep as a test signal: Do your expect different response from the loudspeaker? Why?
2- How to interpret the (very nice) waterfall ? Is it only useful for RT-60? Speaker wall resonances?
3- Is it possible to use REW with Pink noise test signal ? Any advantages to do so?
4- Is it possible to analyse already recorded .wav files, as wity Audacity?
5- I did everything with the Edirol audio capture set at 44.1 kHz. Is that right?
Here again, I'm impressed. Look like a useful software that seems to work very well! Also, a very educative tool for audio enthusiasts, not only engineers...
Thank you
L P Simard
I finally found time to try a little more the REW software that I downloaded 3 months ago, using a ECM8000 + Edirol UA-25. For a "free" download, REW is quite impressive. I wanted to give you some initial feedback. "Vaut mieux tard que jamais" as we said in french.
I started by measuring the frequency response of a small Polk Audio loudspeaker, on a bookshelf, against a wall (The microphone was on a tripod, about 12-15 inch in front of the loudspeaker). The shelf is situated into a fairly small room into my house. I did a comparaison of the result using REW (v4.11) and using the FFT function from that popular "free" software: Audacity. In the latter case, of course, I had to "convert" the result of the FFT into 1/12 octave frequency bands, copying the large text file into Excel...). With Audacity, also, I had to use pink noise as a test signal, instead of a freq log. sweep...
The result?
1-Both curve (REW "smooted" to 1/12 oct, and the curve from Audacity) were very similar (some differences at lower frequencies). So far, so good! A good indication that things seem to work well...The result makes sense anyway for that small loudspeaker on its shelf...
2-REW is (much) easier to use. It's fun too.
3-REW provide a lot of information. For instance the RT-60 (I got 0.2 -0.4 seconds. The room is fairly small and (definitively not empty) filled, so that makes sense - I'll try to calculate it to check).
A few questions:
1- Using Pink noise VS frequency sweep as a test signal: Do your expect different response from the loudspeaker? Why?
2- How to interpret the (very nice) waterfall ? Is it only useful for RT-60? Speaker wall resonances?
3- Is it possible to use REW with Pink noise test signal ? Any advantages to do so?
4- Is it possible to analyse already recorded .wav files, as wity Audacity?
5- I did everything with the Edirol audio capture set at 44.1 kHz. Is that right?
Here again, I'm impressed. Look like a useful software that seems to work very well! Also, a very educative tool for audio enthusiasts, not only engineers...
Thank you
L P Simard
