There are several ways of accessing audio systems. Some of my all-time favorite speakers have been made by Magnepan, a builder of planar magnetically driven speakers which have high resolutions and very low coloration. They are wonderful speakers both sonically and . Notice, however that they are placed in a large size room. This is required to give them the necessary space to breath. Other requirements are that they need very stable and powerful amplifier which is a costly proposition if they are to sound at their best.
What if our room is smaller and we are not able or do not want to spend the money are very expensive associated equipment? And perhaps we are looking for a different type of listener experience that large planar speakers can provided? We are not picking on the Maggies because they are not unlike many other large planar or even large dynamic large speaker enclosed systems. The Maggies represent some of the best speakers available of this type. What type? Speakers which are more like musical instruments placed on the room that a window of the recorded sound (especially if the sound has to do with live well-recorded acoustic performances.) The Maggies are beautiful musical instruments but they do not excel in stereo imaging. They are also very much influenced by the room acoustics in which they find themselves. In fact, they are designed inter-react the listening room.
There is another type of speaker which is designed to be as immune from the room acoustics as a possible. In order to do that the dispersion of the high frequencies in recorded sound must be limited. Furthermore, the front baffle of the speakers must help prevent spillage around the sides, top, and bottom of the speakers to limit any boxy coloration. We want to eliminate edge diffraction as much as possible.
Having a small-sized baffle is an advantage. If the drivers are not coaxial drivers where the tweeters and mid range drivers converge, then the drivers ideally should be close together and phase and time-aligned. This is another reason for a small box speaker. The box should be well-braced and damped so as not to give false resonances. We want only the recorded sound, not the sound of the speakers cabinets.
What we are looking for theoretically is two small points in space from which the recorded sound emerges. The points should not sound small, however. They should sound like open windows on the sound. If they are then their will be sound space behind the speakers as well as to their right and left boundaries. In other words, the leakers must disappear. They should not sound like musical instruments. They should have as little sound as possible, only that of the recorded music. If the recording is done well the music should sound more alive and open.
What we may want is to imagine be transported to the performance space, rather that the performance being transported to our room space. We are talking about true monitor speakers. There speakers need to have wide and frequency response.
And they should be of low coloration so as the human voice sounds human. This low coloration is very difficult to engineer, especially with multiple drivers in the speakers. Multiple drivers mean that different speaker sizes must be matched, but these speakers have different dispersion as well as moments of inertia. The more the drivers, the more complicated must be the crossovers. A few companies manage to pull it off but at great expense. (B&W and Thiel come to mind as excellent examples. KEF for coaxial drivers.)
This is when the small mini-monitor comes in handy. The drivers are more evenly matched. If we are talking about only tow small similar size drivers all the better. If the lower range driver has an extended frequent response, then the crossover region can be placed about the spectrum of the human voice. Any crossover anomalies will not be as apparent. They would be pushed above the range of human voice.
There are significant downsides to small monitors, however. One is that they do not reproduce deep bass. The other is that they have limited power handling capabilities, especially in large rooms when popular and rock music is cranked up. This type of music is usually played loud but the music really has limited dynamic content. In other words, one volume fits all. This is not to say that there is something wrong with listening to this music. However, small monitors are not a good match. They will work in a smaller room when the level of the reproduced sound is not excessive.
What is a good match for small monitors? Music with dynamic range such as Jazz or classical music which, when played, may require occasional power reserves to facilitate the attack produced by some musical instruments during certain passages. Large RMS power is not required but dynamic power is needed. It helps when the speakers are self-powered by built-in amplifiers tailored to the specific drivers.
We still have the problem of low bass and power handling which will limit the loudness of the speakers in the room, even in a moderate size room. Power must be siphoned away from the small drivers so that their distortions levels will be lower because of less cone excursions, enabling them to play louder during the dynamics of the music. The subwoofer is the perfect solution. It will surely extend the bottom end, but more than that, will greatly extend the dynamics of the music.
Of course the bass output of small monitors is increased when they are moved closer to the walls and corners of the room. This is a poor way to extend bass because of increased room reflections and much less stereo imaging. Ideally the monitor should be placed a few feet from the walls, and especially corners. They should be placed on speaker stands that bring them up to ear height. In this way they will sound more open and articulate.
We are writing about a low-cost audio system so we need to eliminate costly amplifiers. The amplifiers need to come with the speakers. The speakers must have good definition and articulation and carry must of the musical range above low bass. They should blend into the room both cosmetically and sonically. Stay tuned for the perfect solution.