I always like to hear what individuals consider to be “good sound”. If you ask for a demonstration of good sound from one person, you get a certain type of presentation, mostly based on what that person does for a living in the music business, whether consumer or professional. A professional wants to hear everything but the sound of the room. The consumer wants to hear everything including the sound of the room. It is an interesting comparison that has similarities in certain areas but none in others.
Professional engineers/producers want to be able to hear everything in the mix. They record numerous tracks and need a monitoring system that will reveal all the nuances of each track. They must be able to recognize each measure in the recording and remember what other take had a better measure to use that was from a previous take. This ability to hear something that was done correctly and substitute it for something not performed as well, is the essence of an engineer.
Acoustical memory is short, although much longer on trained professionals than others. They must be able to hear these take differences, remember that this take had a certain something and the other take had the same but was a little better at something else. The engineer must know without hesitation, which one sounds better and where it is located. These subtle differences and the ability to hear them clearly, enables a multiple take session to be condensed down into one track or final song.
Flat Frequency Response
To hear everything in the mix, the monitor needs to have a flat frequency response. With a flat frequency response, it is easier for the monitor to produce each and every frequency without adding any bumps or dips to the frequency response of the music. It is important that the mix information be revealed in exactly the way it was recorded in order for any electronic adjustments to be made further on down the electronic road.
Near Field Monitoring
To make sure only the recording is heard and not the room, the engineer sits in what is called a near field position. With this position, side wall reflections are minimized and there is less reflected energy from the room’s walls at the monitoring or mixing position. We want more of the direct sound from our monitors, free from side wall reflections, which can add comb filtering effects that blur and smear our images in the mix.
No Room Sound
Room wall reflections confuse the wanted direct energy from the speakers at the engineer’s ears. The engineer want s to hear the direct sound from his or her monitors because that is the sound that travels in a straight line from the monitors to the engineers ears. It is the pure sound without the reflections from the room. Room reflections are part of the room sound and the room creates its own room sound by placing its acoustic signature on the signal by using reflections.
Consumers want to hear everything like the professionals but they approach it from a completely different paradigm. Consumers or another name is audiophile, wants to hear everything that is in the recording. Audiophiles want to hear everything in the original recording. They want to hear everything that is in the recording and have it come through their speakers and into the room they are listening in. This is where the paradigm shifts with professionals and consumers. A different road is now taken.
Hi – Fi Speaker
The hi-fi speaker, unlike the monitor, does not have a flat frequency response. Its response is the response of the speaker in a room. The speaker designer knew that his speaker would be played in a small room where all wall reflections within the room would come into play. The speaker designer knew that his speaker with the chosen drivers and crossover would have a certain sound that included the room sound.
Speaker manufacturers go to great lengths to get their speakers to sound good in a small room acoustical situation. They know that reflections will be laced with the direct sound of their speaker and perceived by the end user as the sound of that particular speaker and manufacturer. They know that room sound created by these room surface reflections will be in their presentation. They design their speaker with a frequency response curve and drivers with certain crossover frequencies to help create a total speaker sound which includes the direct sound, same as the professional monitor, but also takes into account and embraces the room wall reflections.
Certain hi-fi speakers are known for their mid range and vocal clarity and smoothness. Other speakers are known for a tight bass response and a well integrated crossover that tries to make three speakers sound like one. Others have the ability to angle the tweeter, mid range, and bass drivers towards the listener in a vertical plane. All of these designs are created to assist the speaker engineer in creating his idea of what a good sounding speaker should sound like within a small room acoustical environment.
Audiophiles listen to everything in the mix but they also listen to the room. They want individual instrument and vocal separation, dynamic range in loud and soft passages and most importantly, they want a sound stage. A sound stage is the imaginary stage where all the music takes place. It is a virtual stage that places the vocals in one position on the “stage” and instruments in another position on the sound stage. It is created by taking the direct sound from the loudspeaker and mixing in the correct balance of room sound or room reflections.
Creating Sound Stage
Controlling side room reflections in our rooms contributes to our sound stage width. We want our sound stage width to acoustically appear wider than the speakers position in our rooms. We control sound stage depth and length by treating our front and rear walls with diffusion. Sound diffusion treatment makes any room boundary surface acoustically “disappear”. Sound stage height can be increased with a combination of diffusion and absorption installed in the ceiling. Every effort in hi-fi from the speaker design to the room treatments necessary to enhance the hi-fi presentation is about the room sound and its impact blended with the speaker sound.
Professionals want to hear what is in the mix and only that. They do not want to hear any room sound because then they mix for that room sound and then the recording is played in a different room, their recording does not sound correct. If they mixed with bass in their room, then they may have not added any bass to compensate for a recording that when played in another room has no bass. Professionals want only the direct sound from their monitors without any reflected sound from the room walls. Audiophiles or consumers want to hear everything within the direct sound, just like the professional. However, audiophiles want to hear their room sound in the presentation and go to great lengths to treat the room wall surfaces to achieve a more realistic and emotionally involving sonic presentation.