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Here are a couple of audio test tones, which we made some years ago, useful not primarily for classical measurements, but for gaining listening experience on acoustics phenomena, resonances or any other sort of acoustical anomalies which may exist in your room or your loudspeakers.
The usage is very simple, just play the file, and LISTEN/analyze with your brain. You will hear all sorts of unwanted additions to the original signal or its pause, which will clearly reveal any resonance in your listening space, loudspeakers, even the buzzes from the loose objects in the room, or resonances from different acoustical instruments (if you still keep it in the control room ).
The signal itself was generated mathematically, from the program code, quantized to 24bits, written directly into the wav file, without any recording/processing. So you can use it even to test plugins, or equipment? All ideas welcome.
Even though the archive is not that big (~20MB), after extraction, files (avi clips) will decompress into more than 1 GB, so be prepared...
We made avi clips (xvid codec) because this was only way to inform listener which frequency is currently played.
Avi clip which cover lowest audio range, starts from 10Hz, so please be careful with listening levels... increase volume from its minimum very carefully, and control your wofer cone movement visually and/or use your finger very gently to sense it.
This lowest one I use for analyze unwanted noises from motors and suspensions of loudspeaker drivers, it is also useful for testing all (audible) room resonances below 100Hz.
Test is based on Hann wavelet with four periodes. Similar tests is extensively used in loudspeaker design, but often with measurement microphone. Sometimes it is called "cosine tone burst" or similar.
Here is the archive:
All ideas and impressions are more than welcome. Enjoy!
NOTE: "BOZO" in the company name isn't famous clown, but starting letters of names of owners (Bogic Petrovic and Zorica Davidovic)