Let’s consider invisible speakers for three situations: background music, home theater, and critical listening.
Invisible speakers are a good choice for the surround and effects channels.
A great background music system fills the room with accurate, full-range, enveloping music at low to moderate volume levels.
Accuracy is tough to pin down in the audio world. For us, it refers to the percentage variance from the input signal. Here’s an analogy. Let’s represent a musical passage as a 12” square being fed into a speaker system. A ‘perfect’ speaker would reproduce that exact 12” square. But a speaker with inherent distortion will produce something less than a square — perhaps a rectangle with rounded corners.
Measuring the difference between the output and the input gives us a ratio, and thus, a distortion figure. Perfect accuracy gives us distortion of 0%. Typical high-end distributed audio speakers have distortion nearing 15%. Invisible speakers have distortion ranging from 5% to over 50%, with the worst offenders spitting out a lopsided polygon.
We define Full-Range from 55 Hz thru 17,000 Hz (See: Frequency Response). That’s equivalent to an ‘A’ three octaves below middle C, up past the highest notes of any instrument into the ‘atmospherics.’
Envelopment refers to the dispersion characteristics of the speaker — the broader the dispersion, the more musical information you’ll hear as you move about the room. Good envelopment means there are no hotspots or dropouts throughout the listening area.
Moderate Volume is anything under 85dB. Chain saws, lawn mowers, and snow blowers create about 85dB of output, so we’re defining ‘moderate’ as loud, but not too loud.
Invisible speakers are an excellent choice for background audio systems, and in some cases, outperform traditional architectural speakers with broader dispersion and smoother tonal balance.
Which invisible speaker technology is best?)
A great home theater system presents fully understandable dialog, a 3-dimensional soundscape, and palpable bass.
Understandable dialog is imperative in a home theater system — and yet is often overlooked during the design stage. Crisp dialog (and effects) are best reproduced by a narrow dispersion, high-impact directional speaker system. Invisible speakers, with their wider dispersion are a good choice when using 2 per channel. You see, using two invisible speakers stacked atop each other creates the vertical dispersion pattern best suited for vocal reproduction.
3-D soundscapes are built with well-positioned surround and overhead speakers with slight diffusion to enhance the environment. Here’s where invisible speakers shine, and are highly recommended.
Gut-pounding bass is best achieved through dedicated box subwoofers. And yet, invisible subwoofers — when a sufficient number are installed — do an admirable job of filling the room with palpable bass. (See: How does the Live-Wall Sub compare.)
Upshot: Yes, but use 2 speakers per channel for the front stage.
While some invisible speakers have low distortion and admirable
tonal balance, there are no invisible speakers currently available that
outperform audiophile box speakers.