Record vs. Playback
I am always amazed at the difference between the recording process used for music and the playback process environments that individuals use to enjoy this recorded music in. In the recording process, the engineer has to make sure that all instruments and vocals are heard in the mix and that nothing is smothered or buried under another vocal or instrument. Different microphones are used to record vocals and instruments and separate microphones are used to even record the sound of the room. The professional recording engineer has separate rooms that are used to record certain instruments and vocals. Unfortunately, when this recorded music is played back, it is played back and heard in less than ideal environments that do not meet the same standards that it was created in.
Many sonic advancements have been made in the realm of car audio. There are car audio amplifiers that today resemble the equipment we have in many professional recording studios. One can use different amplifiers to power the middle and high frequencies. There are separate amplifiers one can even use to power the bass speakers in our cars, so that no energy is lost in the transient response coverage when a bass note is played simultaneously with a guitar note and the energy from the amplifier needed to produce the bass note does not rob energy from the middle and high frequency vocals and instruments. Bi-amplification and even tri-amplification are popular amplification scenarios today in car audio.
Car Audio Components
There are also many improvements in other components in the car audio signal chain. Digital to analog convertors have also come a long way in their ability to convert detailed, digital signals from our compact discs into analog waves that our ears can hear through our speakers. One can even purchase separate digital to analog convertors that are not integrated into the receiver in the dash. These processors can even send the signal to multiple speaker arrays which are spread out and located in different positions inside our vehicles with the sonic goal of bringing a more lifelike presentation to our mobile music environments. Special care and attention has been given to the number of speakers and the speaker positions inside our vehicles by car manufacturers to try and portray the music in a realistic manner. Electronics “steer” the audio signal to try and produce a multitude of “room sounds”.
Glass Bowl Effects
Unfortunately, all of this technology can not hide the impact of the music inside of our “glass bowl”. Listening to music inside of our vehicles is like listening to music inside of a glass room. Reflections from our windshield and our windows produce a harsh glare that can destroy any musical presentation our mobile equipment is capable of producing. Sound takes on the characteristics of the surfaces that it strikes. If it strikes wood, it takes on the welcomed smooth and warm “sound” of the wood. If it strikes glass, it takes on the harsh and glaring characteristics of the glass. This phenomenon is especially apparent with high frequencies which can produce an ear piercing glare. All of this reflected glare conceals parts of the music. The engineer who created the recording never wanted this to be part of what one heard in his recordings.
We can minimize reflections from our windshields by placing absorptive material on the windshield itself; just kidding. We realize that we must be able to see out of our windshield, but we can treat the primary reflection from our speakers to the windshield with small amounts of acoustic foam that do not interfere with our vision. We can also treat the dash of our vehicles with acoustical foam to minimize reflections from the windshield to the drivers and passengers listening
position. Don’t forget to treat the deck area behind the backseat and rear window. If you do not have rear seat passengers, you can also treat the rear side windows by temporarily placing acoustic foam on those windows. Make sure you are not obscuring any lateral or side vision pathways. Low frequency absorbers can be added to tighten up our bass response. They can be added inside our trunks or even placed behind the rear seats in our sports utility vehicles.
In our room playback systems, we can also do many things to enhance our musical presentations. We can position our stereo systems in our room in a manner that produces a frequency response that is smooth and even with no exaggeration or loss of any frequency groups. We can control side wall reflections at our listening positions by treating them with sound absorption or sound diffusion technologies. Front and rear wall reflections can be treated with sound diffusion technologies that can spread reflections our evenly without any loss in signal. Our ceilings can even be treated to make our ceilings acoustically disappear and make our rooms appear sonically larger. Bass absorption technologies are available to minimize resonances produced by low frequency energy and clean up any muddle or smearing excess bass energy can produce.
Lets meet our recorded music and recording engineers half way and play it back in environments that allow for equal representations or all recorded material. Recording engineers go through great efforts to make sure we hear all of the music the artists use to create their music. They even design separate rooms to record vocals and drums in so that all sounds are captured and represented in the music. We do not need to have separate rooms for our musical playback environments, but we do need to have environments that allow for all the music to be heard and hopefully felt. Lets make sure we listen to the music without hearing the room or the car.