Want to really hear music at an open-air concert

Outdoor music season is coming: a great time to sip wine and enjoy the fresh air and music while sitting on your favorite blanket. You know what’s not so great about outdoor concerts? The sound, which is a problem, because that’s kind of the whole point.

Walls and ceilings play an important role in how we hear music. They absorb or reflect sound waves, or do both bit by bit. A sound engineer’s main job is to control these reflections, because they make a big difference in the audible sound. Imagine a large concert hall: long and narrow, with a hard surface. It’s no accident.

“In a concert hall, you hear reflections from the walls and ceilings,” says Trevor Cox, professor of acoustic engineering at Salford University in England and author of “The Sound Book: The Science of Sound Wonders of Light. “Those extra seconds of sound embellish the music and give you a sense of encompassment. Outdoors, the sounds go away.

So, how can you make the most of an acoustically suboptimal situation?

First, stick to fast music. Some genres need reverb – those that reflect sound waves. Slow-moving pieces benefit from three seconds of lingering sound. It blends the notes together, creating an ethereal feel. That’s why cavernous churches with hard, stone-like reflective surfaces are great places for organ music. Dynamic music, like rock ‘n’ roll and hip-hop, needs less: you don’t want to hear the aftermath of notes when the musicians are already four bars ahead of you.

Outdoor venues usually have little natural reverberation. Sound waves travel up and outward without bumping into anything, and the random objects they bump into, such as grass and human flesh, are absorbing. Even if reverberation were possible, sound engineers wouldn’t necessarily want to use it. They might have to prevent sound from penetrating nearby houses. They also worry about the weather: with temperature inversion-when cold air is trapped under a layer of warmer air-the sound rising up can be reflected back into the audience, fighting unpredictably against new sounds coming from the speakers. The best tactic in these circumstances is to create a focused sound beam.

“Expanded speakers send music in a certain direction, like a spotlight,” Cox says. “You can place speakers with different directivity to create patterns and confine the sound to a very focused area. When you’re swept up in an explosion of that kind of sound, you want rock ‘n’ roll or more upbeat jazz. If you have to go to an outdoor classical concert, try something bright, like baroque music.

Some outdoor environments provide better sound than others. The best place is a seating area with a slant and a stage below. There’s a reason why amphitheaters have been set up this way for thousands of years, and not just to help people from behind see.

“Greek amphitheaters are amazing places,” Cox says. “They seem to have used stage space to add reflections from the floor, and the high seats keep the sound from going through too many heads.”

Position yourself in a spot with an unobstructed line between you and several speakers to improve your listening experience. But that’s not the only factor to consider when holding an outdoor concert.

First, don’t sit too close to the speakers. The sound they produce is intended for people hundreds of feet away, often over several obstacles. Standing only a few feet away is the sound equivalent of drinking from a fire hydrant.

Then find the mixing desk. The sound engineer is usually about two-thirds of the distance between the stage and the back of the auditorium. If you sit close by, you get the sound exactly as the engineer thinks it should be heard.

If the sound engineer is moved away from the stage, you should wander around before deciding where to sit. Different surfaces absorb sound at different frequencies. (For example, manufacturers stuff car doors with materials that absorb high frequencies, so you hear a distinct thud when you close the door, Cox writes in his book.) and high frequencies. It helps to stop and close your eyes once in a while: our heavy reliance on sight undermines our subtle listening skills.