I think Pete's 12 step sound program pretty much answers the question of how to improve your tone quality. I'm sure this is covered there, but I'd pay close attention to 2 things (for a start): 1) Be sure to put lots of air in the horn; it can be fast air for volume, or slower air for less volume, but you always want to fill that horn with air. 2) Watch how you articulate each note; how you start and end the note. Especially be careful to start the note cleanly.
Regarding how you judge your sound, obviously a good recording is one way to do it. But I still think what I hear bouncing off a wall should be a pretty good representation (at least of how it sounds relatively up close). I've read statements in this forum that the sound bouncing off a wall in front of you is not a good way to judge your sound, but would like to know why not. It makes sense that it might sound different in the back of the room, or through a P.A., but that tone bouncing directly off the wall in front of me should be pretty close to the natural acoustic sound of the horn. Any thoughts on this?
I'll admit that articulation was never my strength- I was happy enough just to slack off and get the sound I wanted whilst playing Legato.
Interestingly enough, I was testing out an Ebay saxophone at the same time that I made the recording (it cost $155 including shipping). I noticed that in order to deal with the issue of the sound peaking, and the recording become shrill and buzzing, I had to sacrifice the clarity of the sound. To my own ears, while I was playing, my Yamaha horn had significantly smoother and more event one, especially on the low and high notes. When listening to the recording, I could barely hear the difference! This, of course, could be due to the poor quality of my microphone. Recording myself playing is a good way of reminding myself of what I can improve on, but not really a good gauge of how my tone sounds like, in my opinion.
Thanks for the link, Pete, I visited it last night, and came to the realisation that I was biting too hard. I'll need to work my way back to having a good embouchure again. It's also a great resource for learning the altissimo notes, and other techniques that I want to work on.
I think that my practice will revolve around scales and long notes, as well as working on my embouchure for a week or two at least.
Thanks for all the help.