The Sounds of OEM Audio

There are few people who know more about automotive audio than the people at HARMAN as the company has Bang & Olufsen, Bowers & Wilkins, Harman Kardon, Infinity, Lexicon, Mark Levinson, and Revel in its portfolio, which encompasses car brands ranging from Audi to Volvo.

According to Arndt Hensgens, HARMAN’s chief engineer of acoustics, developing the right sound for a vehicle interior is exceedingly challenging. He points out, “There is a huge range of materials – plastic, cloth, leather and glass – which all absorb and reflect sound waves at different rates and every model has a different shape cabin, adding yet more complexity."

Which means that there are differences even within the same vehicle, depending on the trim.

So how do they do it?

Hensgens says, “Car audio is a long and delicate process that combines technology but most importantly, the human ear. Each model-specific car audio system is meticulously tested by HARMAN’s trained team of audio specialists, nicknamed ‘Golden Ears’ for our abilities to hear subtle audio differences.”

So what do these Golden Ears listen to?

The top five pieces of music are:

“Fragile” by Cassandra Wilson

“Walking on the Moon” by the Juri Horning Trio

“Fields of Gold” by Eva Cassidy

“Colour to the Moon” by Allan Taylor

“Pictures at an Exhibition” by Modeste Mussorgsky, performed by Fritz Reiner and the Chicago Symphony Orchestra

Yes, you can try it at home.

What they are listening for are bass response, spectral uniformity, spatial imaging, and dynamic capability. Which probably explains why they have Golden Ears and the rest of us probably don’t.

Not all of the testing is done within the confines of acoustic chambers, however. They also take vehicles out on the road to make the adjustments required.

“We use the car on tracks and roads of varying surfaces,” Hensgens says. “The speed, road surface, number of passengers, the roof being up or down, even if the car is petrol or diesel: all elements affecting the audio.

“We also consider the type of music a person buying that particular car would listen to. Only when we’re happy that the audio is at its finest will the system be signed off for production."