Testing a Concert Hall
It’s always fun to see how different kinds of engineers test what they do. For example, acoustics engineers must test their concert halls – something that’s especially important for classical music halls where the performers are not equipped with microphones. In New York City, the venerable Alice Tully Hall in Lincoln Center has been undergoing renovations for the past couple of years. Now the construction is nearly complete, and this recent article from the New York Times describes some of the acoustics testing taking place. It’s surprising how many parallels there are to software testing:
Functional Testing – The new hall has movable stages, remotely controlled noise dampeners, sophisticated noise shapers, and more. Each of these needs to be tested to make sure they work in a variety of conditions including with multiple instruments, performers, and performer locations.
Beta Testing – It’s not enough for the acoustics engineers to say the hall works as expected. Actual audience members must provide feedback to make sure the hall sounds great from every seat. For good results, the audience needs to remember that they’re not just enjoying a performance, they’re there to help the engineers refine their design. That means sitting through multiple stage adjustments and providing useful feedback at each step.
Load Testing – Load testing the acoustics of a performance hall may seem odd, but there are big differences between the acoustics of an empty hall and a full hall. People – bodies that is – absorb sound by simply sitting in their chairs. Good acoustics testing requires filling the hall to make sure it sounds just as great with a large crowd as it does with a small crowd.
Apparently the feedback has been outstanding for the new Alice Tully Hall. Hopefully once it reopens, New Yorkers will be proud of their newly renovated concert hall.
Wow, this blows me years ago when I was working as a sound engineer back in the UK. Acoustics is a very complex yet fascinating world and indeed it can have similarities to the software testing world. Actually this is the case with all acoustic & recording worlds in which both similar tests can be conduct during actual recording & mixing/mastering stages. As recording are based on ‘pure’ inputs (either Mic/Line or Midi inputs), the whole process of recording, editing & mixing is actually a lone test procedure.
During studio setup the engineer tries various setup possibilities which may include:
* Instruments setup
* Microphone setup
* Type of microphones and the amount to be used (e.g. a drum set can be recorded by 2 mics to 10 mics or more!)
* Use of acoustic boards/foams
* Use of acoustic effects (e.g. Reverb springs/boards)
* Use of Digital processor effects (e.g. Reverb springs/boards)
* Actual instruments and their timber.
After all parts have been recorded, starts the fun part.
From here the possibilities are virtually endless: Sound Modules, Effects, Editing techniques – all can be used for producing a complete new sounded result of the recorded one. Think of this as an infinite matrix of sound possibilities and the engineer is the ‘mad professor’ who stirs the sonic cauldron and concocts new sonic recipes.
What would have been if Jimmy Hendrix didn’t use his Wah-Wah pedal?
What if Pink Floyd did not use their synthesizers?
What if legendary Psychedelic rock bands such as Jimi Hendrix, The Grateful Dead, Big Brother & the Holding Company, Jefferson Airplane, The Byrds, Pink Floyd (before the album Meddle), and The Doors would not experience illegal drug use while recording their songs?
I see them all as big & significant testing pioneers which we awe them much for their contribution & daring!
What do you think?
Bernard.