Obviously I enjoy the subject of audio. So please indulge me in this. The above mono vs stereo discussion reminded me of the following subject.
I've always been frustrated when the tower speaker mounting positions are greatly offset in the front to rear depth. Why does this matter?
For example, if the speakers were to be offset by 2 feet, then from around 200 to 350 Hz you will have a progressive null in the response with a deeper cancellation centered at 275 Hz. And that is an area where you need all the lower midrange warmth that a tower speaker can give you. But it also smears the time alignment of all frequencies. That's a very real and audible form of distortion that sacrifices coherency. For instance, with two speakers staggered at 2 feet, at around 8 kHz, that very piercing area of the treble, one tweeter is propagating that frequency 15 times more than the other. Up until now, the tower dictates the speaker mounting positions and there was absolutely nothing you can do about it. Up until now. With Digital Signal Processing and the right amplifier channel make-up you can do total time correction.
Also, with a horizontal array, by fanning out the speakers and using center to outside time delay, you can eliminate for the most part any off-axis time smear and comb filtering....that's when listening off-axis, the far left and far right speakers are at different distances from the listener perception point and tend to partially sum and cancel at various listening positions and at various frequencies.
This solution can also greatly impact the subwoofer to tower speaker coherency, especially if you choose a particular focal point behind the boat based on the way you use the system.
Many will say you can't get good sound quality in a boat. That's certainly true when on plane, with engine noise, wind noise, and the hull slapping against a little chop. But that is not the only scenario of how people listen to music on and around their boats. With a boat you definitely have some disadvantages. Like the fact that sound energy flash dissipates in open air. But with that comes certain advantages. On the flipside, in an open boat you have almost exclusively the incidental radiation, meaning the originating sound only and without interference from reflected energy. If you understand this, you can use it to your advantage, especially in the way you tune a boat system differently from a car system. In contrast, in an enclosed car, truck, or SUV cabin, there are six sides folded around you and your speakers. Yes, that definitely tends to preserve the sound pressure level, but it also creates as much reflected radiation as incidental radiation. And this causes problems with standing waves, both in positive-reinforcement and in negative-cancellations. Again, things that you are fortunate to avoid in an open boat.
Just food for thought. There are others that are building these type systems today.
