Aaron.
After listening to and considering many commercially available options, I've now decided to go this very route myself with my monitors-to-be. My studio will be no-compromise in almost every other aspect, and since budget is limited, I'm pretty sure I will get most bang for the buck with a set of 'home made' monitors applying drivers normally used in VERY expensive speakers. As I'm new to speaker building (yes, I am self confident), It'll take LOTS more education before I actually start building, but here's my plan so far:
IMO, the trickiest part of speaker building is the merger of the drivers through the crossover circuitry, especially in three- (or more) -way speakers. I've escaped this problem with a very classy active solution, using a digital xover (Behringer DCX2496) which splits the 24/96 signal from my digital mixer into three stereo signals. The DCX allows for easy trimming of xover freqs and slopes, equalization, plus miniscule time alignment between bands (to compensate for driver alignment if need be). After that, the signals are converted to analog and go to three stereo power amplifiers which drive the treble, mid and bass drivers separately and independently. This way, the amplifiers will have no other circuitry to 'worry' about, only the drivers themselves, resulting in a substantial loss of distortion etc.
Another tricky part is constructing a ported system, especially with a front facing port, which You'll need for soffit mounting. That's why I'll go for a sealed enclosure system.
Here's another reason: speed. A sealed enclosure is much easier to get right for a novice, but it also has generally better transient response. Punch. Well defined bass. Me likes.
I'm also going for a highly damped, dry, unresonating, 'unforgiving' character, which to me is essential for studio monitoring. It isn't as essential to all manufacturers, mind You. Sure, it's great to try Your mixes in an average consumer speaker as well, but make Your crucial choices with proper maximum definition tools is what I say.
One of the compromises commercial speaker manufactures face is that of size, which affects frequency response extention in the bass region. I (like many who consider soffit mounting) can make my speakers very large if need be (and probably will). I'll probably also put the mids and trebles in one box and the bass drivers in separate enclosures right next to them or below to minimise resonance interference.
The drivers I'm currently considering are RAVEN R1 (or R2) for treble and Focal 5W4211 for the mid. I haven't decided on bass drivers yet. The RAVEN is a ribbon tweeter with great FR extending into some 35kHz. The major benefit lies in its transient response, though, since the diaphragm is practically weightless. Distortion is also veeeery low. I might go for a planar tweeter instead of a ribbon, as they're less sensitive but exhibit similar characteristics. The Focal mids have a very flat response in the pass band and I'll probably use two of those in a Mid-Tweeter-Mid (D'appolito) configuration.
The woodwork in itself is equally important. Cabinets have to be right size, rigid and as unresonating as possible, but there's loads of information on this on the web, although You probably won't get away with less than substantial handiness...
I'm guesstimating that my system will cost about (quick conversion from Swedish kroner...) somewhere between €2000 and €4000 (probably the latter), of course not counting the work hours I'll put into it myself. It largely depends on what power amps I'll choose eventually. It is my firm belief that I'll end up with monitors far superior to anything commercially available for the same amount of money.
As far as the actual soffit mounting is concerned, this won't be any different from soffit mounting any other monitor. Remember, the cabinets need to be physically decoupled from the surrounding wall to minimise resonance, so building the speakers straight into the wall would be a rather bad idea IMO (if that's what You mean).
Any thoughts from 'master' barefoot?
/Chris
