In the last few days, a contingent from the AES-TAMABA Student Section, along with students from the "Architectural Acoustics" course in the Technical Superior Sound and Recording program at TAMABA Institute, led by Professor Indio Gauvron and Faculty Advisor Gustavo González, carried out the first experience and trials with the aim of estimating the sound absorption coefficient in the spectrum of different material samples, based on a rudimentary and quick method that involves comparing impulse reflections.
Due to logistical, volume, and acoustic space considerations, we chose the main hall of the Centro Asturiano de Buenos Aires, located at 475 Solís Street in the Autonomous City of Buenos Aires. For the experiment, we used a Samsung PC, an AVID Fast Track Duo interface, and measurement microphones from the ARC and ECM8000 brands by Behringer. Impulses of 3 samples, 6 samples, and 10 samples were provided by Professor Indio Gauvron and were played back through an ALESIS audio monitor in its M1 model.
The idea behind this method is to obtain IRs, discard the "direct" reflections (monitor-microphone), and, with a suitable time window, along with the reflections (direct reflection; reflection with sample), then, using FFT or DFT (depending on their length), obtain both spectra and compare them to determine level differences. With these results, we calculate alpha using the A = 1-R model.
We conducted several measurements and recordings before commencing with the data processing and analysis. In the evening, during the weekly meeting of the Section, we shared the experience with students who couldn't attend.
We remain focused and hard at work!
