OK, I started at the beginning with the intent (or at least hope) of reading the whole thing.  This really looks promising.  The second chapter on statistics was a little dry but I'm sure quite necessary.  The author does succeed (at least so far) in avoiding inscrutable mathematics.  The reader must have some math expertise (such as understanding things like the sigma symbol indicating iterative summing).  Some computer code is also present - Basic is the language used in presenting examples, but it's easy enough to follow even if you've never used Basic.  You possibly don't need any programming expertise all, but I suspect it helps.

Try the blog link at the site.  There are a bunch more pdfs for general electronics, fabrication and other good stuff.
 
Back in the day (mid 70's to mid 80's for me) chip reps use to visit once a quarter.  After returning from taking the engineers and purchasing agents to an extended lunch they would bring all the techs out to their car, open the trunk and grab as many manuals, cookbooks or spec sheets you could carry.  I'd get double loads to share with the electronics department of the local community college.  Seems the reps never hit the engineering or tech schools in the area.

Oh what fun!  I just need another life time!

If you find this reference too daunting, you might try "Digital Audio Explained for the Audio Engineer" by Nika Aldrich. A much lighter read, but not overly dumbed-down.
 

I actually just finished reading pretty much the whole thing (the online book, not the one Dave just recommended).  The author does a remarkable job of staying away from complex arithmetic (complex as in real and imaginary components to a number).
 
The final six or so chapters are supposed to get into the really deep stuff, but it turns out that the online version of the book has the content of those chapters mostly missing (mercifully missing, I might speculate).
 
This really is a pretty remarkable text for those with sufficient interest.  I came away with a pretty solid understanding of how convolution works in the time domain.  Of course, any software doing convolution on all but really short segments is going to use FFT.  That is pretty thoroughly explained as well, but I can't claim more than a vague theoretical understanding of how convolution works in the frequency domain - coding this stuff must be a real <rhymes with ditch>.
 
By the way, thumbs up for Dave's recommendation as well.
 
 
 

dmbaer
This really is a pretty remarkable text for those with sufficient interest.  I came away with a pretty solid understanding of how convolution works in the time domain.  Of course, any software doing convolution on all but really short segments is going to use FFT.  That is pretty thoroughly explained as well, but I can't claim more than a vague theoretical understanding of how convolution works in the frequency domain - coding this stuff must be a real <rhymes with ditch>.

Not having read the book in question (it may have been covered), but the short answer is:
 
Convolution in the time domain is the same as multiplication in the frequency domain. 
 
Convolution in the frequency domain is the same as multiplication in the time domain.