The sound in the hall
The Rapallo installations team has been quite busy in the last few weeks and months. One of the projects we are particularly proud of, is one of our latest school projects. And it is all about the sound in the school hall….
Remember the assemblies, plays, performances, …. In your primary school hall? Whether the memories are fond ones or not, fact is that the traditional kiwi school hall is a place that takes a special place in the heart of many, many kids. And traditionally, you would not link a school hall with an impressive audio experience. Guess, what? We’ve just changed that!
When the Rapallo installation team was approached by Glenfield Primary school to upgrade the old audio system of the school hall, we scratched our heads. The challenge was to stay within a reasonably low budget but still produce a decent sound in a building that is more or less a natural enemy of good acoustics.
Many kiwi school hall was built in the 1950s-70s with a timber floor, usually timber lined walls up to about 2.4m high, and then concrete or timber paneled walls going up to a tin roof ceiling with – at best – some plywood lining. The echo in these halls are often almost as powerful as the French Alps. Try yodeling in your school hall next time and you will catch my drift.
The school definitely had no budget for any acoustic paneling which could remediate this problem, so we applied some common sense and kiwi ingenuity to the challenge. Instead of installing 2 monsters of speakers alongside the main stage, as is custom, we installed 4 speakers in a much more practical layout.
In a traditional layout, 2 speakers are used to fill the whole space. That means that the sound is too loud close to the stage and not loud enough at the back of the hall. On top of that, the reverberation of the hall makes the sound atrocious.
Instead, we added a second pair at the back of the hall and we hooked them up to a second zone amplifier so we can now independently control the volume of the front 2 speakers and the back 2 speakers.
And thanks to physics, there is an added bonus to this setup. Because the back speakers are emitting the same waves as the front speakers, instead of hearing reflection, you actually have a very clear sound everywhere in the room. Destructive interference of the reverberation waves that clash with the sound waves coming out of the back speakers, result in much less of the echo-effect than before.
Thanks to the Apart Audio setup of pre-amplifier and power amplifiers, we managed to fill the space with nice bass, good mid frequencies and enjoyable high frequencies. A dedicated amplifier looks after the stage monitor speaker.
ICT lead for the school, Scott Hillman, had this to say about the project: “ We engaged Rapallo because they listened to our needs and came up with a plan within budget that solved our problems. We now have a wireless connection to the Projector and the sound system via Chromecast, and we can still use our old microphones. They sound clearer than they ever have. And the sound of the music is excellent.”
Everybody is happy, and you know that’s how we like it.
