AND
ways to use it to measure, characterize,
and correct for various audio system issues.
Presented by
JJ Johnston (and others)
of
The PNW AES Committee
9am-4pm, Saturday, January 28th, 2012
Old Redmond Firehouse Teen Center
Redmond, WA
This will be a FREE all-day workshop/seminar, with breaks interspersed and a no-host lunch.
In the 9am-12pm morning session, JJ will explain what a Fourier Transform is, and what it's for, in NON MATHEMATICAL terms. Then he will explain some of the ways that an FFT (that's Fast Fourier Transform) can be used to measure, characterize, and correct for various kinds of audio system issues, audio testing, and the like. The talk in the morning will use "Octave" which is a freeware package available from sourceforge, that runs on windows, linux, and OS-X.
We will show how to get this freeware and install it (although we won't do that in real time due to practical constraints). If you're anxious, the link is given below. We will set up a measurement system and show the Octave commands that can be used to run an actual room probe, ThD probe, and the like, in near-real-time by using the combination of Audacity (for capture) and Octave (for analysis).
We will discuss issues like windowing, time resolution vs. frequency resolution, and what "smoothing" in the frequency domain means in the time domain. The morning session will be somewhat of a hands-on lecture, as JJ, after showing the basics, will show how to do a variety of things in real time. The Octave scripts will be shown on the "big screen" next to the results they calculate. In short, you will get to see some of the processes that are going on inside of your various boxes.
This should easily take us to lunch, and attendees are welcome to either enjoy a BYOSL (bring your own sack lunch) or to go to one of the many fine eateries nearby. Given that you will need to drive to your lunch destination, we'll take an hour for lunch, which should be more than enough time.
In the afternoon, Bob Smith and Dan Mortensen will present an overview of acoustic measurement systems. The topic includes the basic signal flow for single and dual channel systems, system calibration and a more detailed comparison of measurement microphones. Then a number of commercial and free analysis systems will be discussed. Differences are highlighted between dedicated hardware, pre-integrated, DIY-integrated and complete DIY systems. Following the slide presentation, Dan Mortensen and Bob Smith will demonstrate several analysis systems in action including Meyer Sound SIM and SmaartLive v7. Time permitting one or two others may be briefly shown.
*********************
ways to use it to measure, characterize,
and correct for various audio system issues.
Presented by
JJ Johnston (and others)
of
The PNW AES Committee
9am-4pm, Saturday, January 28th, 2012
Old Redmond Firehouse Teen Center
Redmond, WA
This will be a FREE all-day workshop/seminar, with breaks interspersed and a no-host lunch.
In the 9am-12pm morning session, JJ will explain what a Fourier Transform is, and what it's for, in NON MATHEMATICAL terms. Then he will explain some of the ways that an FFT (that's Fast Fourier Transform) can be used to measure, characterize, and correct for various kinds of audio system issues, audio testing, and the like. The talk in the morning will use "Octave" which is a freeware package available from sourceforge, that runs on windows, linux, and OS-X.
We will show how to get this freeware and install it (although we won't do that in real time due to practical constraints). If you're anxious, the link is given below. We will set up a measurement system and show the Octave commands that can be used to run an actual room probe, ThD probe, and the like, in near-real-time by using the combination of Audacity (for capture) and Octave (for analysis).
We will discuss issues like windowing, time resolution vs. frequency resolution, and what "smoothing" in the frequency domain means in the time domain. The morning session will be somewhat of a hands-on lecture, as JJ, after showing the basics, will show how to do a variety of things in real time. The Octave scripts will be shown on the "big screen" next to the results they calculate. In short, you will get to see some of the processes that are going on inside of your various boxes.
This should easily take us to lunch, and attendees are welcome to either enjoy a BYOSL (bring your own sack lunch) or to go to one of the many fine eateries nearby. Given that you will need to drive to your lunch destination, we'll take an hour for lunch, which should be more than enough time.
In the afternoon, Bob Smith and Dan Mortensen will present an overview of acoustic measurement systems. The topic includes the basic signal flow for single and dual channel systems, system calibration and a more detailed comparison of measurement microphones. Then a number of commercial and free analysis systems will be discussed. Differences are highlighted between dedicated hardware, pre-integrated, DIY-integrated and complete DIY systems. Following the slide presentation, Dan Mortensen and Bob Smith will demonstrate several analysis systems in action including Meyer Sound SIM and SmaartLive v7. Time permitting one or two others may be briefly shown.
*********************