Demonstrations: Acoustically sound

If you’re selling hi-fi, or home cinema, and using a demo room to help you do so, good acoustics are an essential element, says tech journalist Rob Lane

Everyone building a new demo room is aware that the acoustics of the room have a huge bearing on the sound, but that doesn’t mean they pay it enough respect, or get it right when they do.

“Acoustics are often neglected as part of the demo room design process,” explains Emma Bigg, founder/director at acoustic-savvy AV consultants Octavius RE. “This is almost always due to lack of understanding.”

Chris Adair, founder/MD of Adair Acoustic, agrees: “Not only do people not have any idea what makes a good-sounding room, but the industry is filled with rumours of companies that tried to design the acoustics of their demo rooms and created spaces that were ‘dead’, ‘uncomfortable’, ‘killed the image’…”

Demo rooms need to look appealing, so, as a result, aesthetics often trump sound quality – going against the grain of what the demo room was originally supposed to achieve: great sound.

Mr Adair adds: “Looks win out and a demo room is more often than not constructed on a wing and a prayer that the acoustics will turn out fine – and they frequently don’t.”

One of the excuses for bad acoustics – or even for not bothering to try for decent acoustics – is that the customer isn’t going to have a great acoustic space at home, so why make the demo room brilliant? This is just a convenient cop-out.

“The key is not to create a real-life situation – it is to demonstrate the characteristics of the products,” says Ms Bigg. “Besides, no two listening rooms are the same and you couldn’t possibly recreate all the variations. Making the product sound good in the client’s real-world space is part of the after-sales service.”

A pricey loudspeaker needs to be heard in the best possible acoustic environment– so why demonstrate it in inferior, living-room conditions?

“Play them a great system in a great demo room and they’ll be working out how they can get this experience in their own home,” says Mr Adair. “In a great-sounding demo room, you are already off on the right foot. However, if you start with a terrible acoustic environment, then nothing will sound great.”

Mr Adair knows this only too well. In 1992, he built a high-end demo room that “cost a small fortune at the time” for his previous company. He had the room isolated – a room within a room – and parachuted in a professional acoustician.

However, because of the team’s fear of a ‘dull room’, they kept the acoustician focused on the isolation and sound insulation, keeping him at arm’s length for internal acoustics advice. This was, according to Mr Adair, a hugely expensive mistake.

“At the time, I had a little knowledge,” explains Mr Adair. “And as we know, a little knowledge is a dangerous thing. This turns out to be especially true when it comes to acoustics.”

Following the disappointment of the failed demo room, the business moved away from high-end hi-fi into custom installation, and Mr Adair left to do a degree in acoustics.

Today, he runs Adair Acoustic, headquartered in Devon, with offices in London, concentrating on performance and reliability, for hi-fi, home cinema, home technology and lighting – along with some commercial work.

“Ideally, you want a room that is lovely to talk in as a starting point,” he says. “But for music, you need the room to ‘sing’ a bit: you need it to reinforce the sound gently. A little reverb is always nice, but it has to be just a little and it should be diffuse, and the bass needs to be controlled in proportion. This way, you clearly hear the direct sound from the speakers and have the ‘rose tinting’ of the room’s lovely acoustics.”

“You are looking to minimise any effects of the room so the customer is just hearing the product on demo,” adds Ms Bigg. “This allows the customer to make an informed judgement about how a product compares with more expensive alternatives.

“With home cinema, you should be looking to achieve the same acoustic standards as pro cinema – essentially to create a ‘zero sum’ room. So, very low reverberation time, no or minimal early reflections. You should just be able to hear the speaker – very pure, very clean.

“To really suspend your disbelief, the room has to vanish acoustically – and so if you can achieve this, the experience is incredible.”