Re: My recent ventures into DIY audio...
Building a "point source" box using off the shelf components is a fun and challenging learning experience. A little experimenting, tweaking and patience can yield reasonable results in situations that are not critical. Here's a little test for any of us homebrew builders. Take your best sounding effort. Put two of them next to each other with the backs touching. Now start spreading the fronts apart with the backs still touching until you find the angle where they are transparent in their coverage patterns and the frequency response sounds smooth and consistent everywhere within the combined horizontal coverage pattern. The search for the holy grail. This is what separates the big boys from the rest of us.
I have been in this business quite a while, and can remember specifically a bunch of times "when the light bulb came on"-or at least started flickering.
We have a local 2500 seat venue that I used to do concerts in all the time. I knew it well and always took out the same system-4 stacks per side (all with 90°) horns There was a bit of "splay" in the cabinets to get a little bit wider coverage.
Now before you start jumping on me-this was back in the 90's-and there was not the information base/availability of basic audio/acoustic/interactions etc. Yes it was known and studied-but not redily available to the "common folks" like myself-out in the trenches.
Anyway-I did a wedding in the same room-same stage-but only used 1 stack per side because it did not need to be concert level and they didn't have the budget for a larger system.
Both myself and my righthand tech both said "WOW it is not as loud as the full system-but it sure does sound a lot better-clearer etc".
I was not sure exactly why-but it was the interaction between the boxes that was causing the sound to not be as clear as it could be. The regular "full system" sounded just fine-UNTIL I heard a clearer system in the same room.
When I had combfiltering explained decently to me (THANKS PAT BROWN AND SYNAUDCON), it started coming together and making sense.
When your frame of reference is better-THAT is when you start to realize all the "little things" that make a difference. All the little things DO add up.
Nobody will argue that a single box sounds better than multiple boxes. Of course the problem is getting a single box loud enough to do a large crowd. THIS is where the real design work begins. You either need to use multiple boxes that work well together without interaction-or you need a really loud single box.
This is accomplished by just piling a bunch of drivers in a box. Not so bad for the lows and mids-but once you start to get to the high freq-THAT is the problem area. The size of the wavelength and the physical size of the drivers really fight each other.
Once you start to think of audio in terms of the size of the wavelength-everything starts to change (in the way you look at things).
I'll stop now before I start to ramble on.
