By the Sounds of It

When I was studying sound engineering and first heard of psychoacoustics, I had this picture in my head of a serial killer who beats his victims to death with a guitar (or something to that effect).

In reality though, psychoacoustics is a very real field of study, dealing with the way sounds are perceived and our physiological responses to sound. I must admit I was fascinated by this, and the more I learned about how certain frequencies, or combinations of frequencies, influence our physiology, the more I understood how certain pieces of music could elicit such an emotional response; how certain sounds in film soundtracks can build so much tension; and of course how the sound of a great engine or exhaust can make a grown man smile like a six-year-old on a sugar high!

Whether you prefer the metallic scream of the E46 M3’s straight-six, the soulful howl of a Porsche flat-six or the iconic burble of a cross-plane crank V8, us petrolheads simply cannot resist turning our heads to see what is making that glorious racket. Whether it’s the snarl of induction noises, the rumble of a wide open exhaust system or the cacophony of chirps, tweets and whistles you can get from a turbo that turns you on, the sound of a car has a huge impact on its appeal.

Frighteningly, it’s an art that almost went missing for a while.

Old cars sounded great, because that’s just the noise they made. The exhaust systems were not very efficient at silencing the engines and their intake systems didn’t have big dampening air-boxes to kill the induction noises. The engineers focused on making them perform and the sound was simply a by-product. They weren’t tuned or artificially engineered to sound a certain way – that was just the noise they made.

The iconic GT40, for example, had an exhaust system known to enthusiasts as the “bundle of snakes.” The exhausts from selected cylinders were crossed over to the other bank of the V8 engine, as engineers worked out that the timing of the exhaust pulses would draw more air into the corresponding cylinder on the opposite bank. This was purely a performance design, but it gave the GT40 an incredibly distinctive sound.

Likewise, the 4-rotor engine of the Mazda 767B was designed to give ultra-high performance from a smaller displacement engine, but the high RPM rotors sounded unlike anything anyone had ever heard before. I might not be able to tell you what races the 767B ever won, but I know what it sounded like!

Fast forward a few years and suddenly loud exhausts were considered antisocial, which meant it was suddenly more important for a car to be whisper-quiet than it is to show off its singing talents. We went through a (horrible) period in car history where those sounds we all love to hear on a Sunday morning were all but lost!

Luckily, some auto-makers have always known that the sound of a car (and particularly a sportscar) is extremely important. Jaguar have always made their cars sound great; even the subdued and civilised models sound fantastic. Porsches have always sounded spectacular and now that some models have 9,000rpm redlines, they really sound beautiful! Mercedes gave us the AMG range with sonorous V8’s that conjured up images of muscle cars on the open road.

When Lexus designed their LFA supercar, they called on the expertise of Yamaha’s Centre of Advanced Sound Technologies to help them not only create the iconic soundtrack of the LFA, but to ensure that the engine sound reaches the driver in the most effective and clear way without being obtrusive. Yamaha even called on their musical instrument designers and spent millions to develop physical, acoustic treatments for the car so that they would not need to use any electronic or artificial interference to make the car sound good from both inside and out.

Thanks to these, and a few other car makers, the importance of noise has been rediscovered. These days, almost every single major car company employs teams of sound engineers that fine-tune exhausts, intakes and insulation to make their cars sound exactly the way they dreamed of. They create resonators and active exhaust valves that change the sound of the car when being driven in anger. Even my 15-year old BMW was fitted with a “sound generator” that basically pipes the induction noise into the cabin.

Car noises are now big business!

Some of these innovations have made modern sports cars sound a little bit artificial though. As an example, the new F-type with its pops and crackles coming from the exhaust is perhaps jumping the shark a bit, but it does make it sound very angry and exciting. Audi actually developed a system that injected small amounts of fuel into the exhaust to make it bark, crackle and pop on gear changes and when coming off the throttle. The thing is, as stupid and pointless as these systems are, and as much as you KNOW it’s not real; when the back of your car sounds like machine-gun fire – you can’t help but have a massive smile on your face.

My current daily driver is a damn-near 20-year old Isuzu KB. A boring, uncomfortable, practically agricultural commercial vehicle, but I absolutely love the damn thing for two very simple reasons…

Firstly it has more power than the chassis can realistically handle, which instantly makes any vehicle fun to drive. Secondly, the V6 tucked away in its nose makes an absolutely fantastic noise. Over time, the baffling in its exhausts has worn out and due to rust, some of the silencers have been removed and replaced with straight pipes, making it quite loud. A vehicle that I should hate has actually become something quite brilliant simply because of the way the sounds make me smile. I drive around on freezing cold mornings with windows open and the heater on, just so I can listen to it growl and pop as I blast under another bridge to hear it echo off the walls.

Sound is obviously important to us, but where does that leave us in an electric future of quietly humming transport appliances? What about the stupid downsizing trend making its way into cars like the Boxster? I can’t decide if it sounds like a posh Subaru or a broken Porsche…

To be honest, I’m quite optimistic.  Porsche offer plenty of alternatives with 6-cylinder engines that sound fantastic. Dare I say it – I would be keen on driving something electric as a daily, but only if that means that petrol and oil reserves are saved for enthusiasts who appreciate the seductive chorus of suck-squeeze-bang-blow.