What about if you can use an open source software to do quick measurements during gigs and improving the reproduced sound quality of that scrappy club you used to play in?
This is one of our next challenges: to develop a module for ExpoChirp for PA system calibration and room correction.
Katja is doing an amazing study on long FIR filter with low latency.
This the third test performed in a large meeting room in my office in London (UK).
It is a quite large and acoustically lively room because of the glazed facade and all the hard surfaces but with carpet on the floor.
The ambient noise was quite loud as the air condition system was on (about 55 dB(A) in the center of the room measured during a 5 min period); this demonstrates the qualities of the ESS technique of being able to measure trustable results even in a noisy environment.
The test has been performed using our test loudspeaker (GENELEC 8030A) and an omni directional measurement mic (Earthworks M30) through a EDIROL UA-101 soundcard.
The measurements have been performed with 3 different software using the same settings for test signal lenght and recording (EASERA, Aurora plug-ins, ExpoChirp).
Results comparison are only between EASERA (top) and ExpoChirp (Bottom).
This the second test performed in a small meeting room in my office in London (UK).
It is a quite small and acoustically lively room because of the sloped roof with a funny shape and all the hard surfaces.
The test has been performed using our test loudspeaker (GENELEC 8030A) and an omni directional measurement mic (Earthworks M30) through a EDIROL UA-101 soundcard.
The measurements have been performed with 3 different software using the same settings for test signal lenght and recording (EASERA, Aurora plug-ins, ExpoChirp).
Results comparison are only between EASERA (top) and ExpoChirp (Bottom).
This the first test in my project recording studio in London (UK).
It is a quite small and acoustically dead room because of the light weight roof and a lot of household stuff around.
The test has been performed using one of my studio monitors (EVENT ALP 5) and an omni directional measurement mic (Earthworks M30) through a Focusrite Saffire LE soundcard.
The measurements have been performed with 3 different software using the same settings for test signal lenght and recording (EASERA, Aurora plug-ins, ExpoChirp).
Results comparison are only between EASERA (top) and ExpoChirp (Bottom).
Here you can find the paper presented at the PD convention in Weimar (DE) in August 2011.
Here you can find the paper we have presented at the latest Reproduced Sound conference in Brighton (UK).
This is the link, on Katja’s website (check it out if you are into PD programming - brilliant stuff), where everyone can download the latest stable and tested version of the software.
Updates will be posted as soon as the tests are finished.
Beta testers and programmers who would like to partecipate in the development are welcome, just drop us a private email.
ExpoChirp is a Pure Data (PD) implementation of a typical Impulse Response (IR) measurement tool often used for professional acoustics and audio measurements.
It is based on Exponential Sweep Sine (ESS) technique presented by Prof. A. Farina of Parma University at the 108th AES convention on 19-22th February 2000 in Paris, France.
The ExpoChirp project aims to be a cross platform open source implementation of up to date IR measurement and analysis techniques. ExpoChirp modules show graphical data in all stages of the measurement procedures and this enables users to assess the working, specifications and quality of the implemented routines, which is useful for education purposes and for special cases in real life IR measurements, as already described.
The ExpoChirp project was initiated in 2010 at the Pure Data forum by bassik and katjav.
Only basic modules for test signal generation, test response recording, IR editing, spectral analysis, and convolution filter testing have been programmed using third party PD class objects together with self developed PD objects like the test signal generator module.
This blog is intended to show all the progress we are making on the development of the software and all the new features that will be added.
This link brings you to the original Pure Data Forum discussion.
No progress in the software development will be shown on the forum without being published on the blog.
