Links
I have found several sources of information invaluable. I have also learned what it's like to teach yourself using peer information from forums and other web sites. You need to find people who really understand what they are talking about and validate what they are saying. Usually by looking at their projects and how they present their results. It's very easy to be misled by both egomaniacs and well meaning people who have misunderstood something. (Over the years, I've found myself on both sides of both of these fences).
The best sources of information I have found so far (the insights, careers, and intelligence of these men are awesome):
Rod Elliott; His huge web site covers everything analog (with some digital projects sprinkled in), from line level circuits to power amps, speakers (to a lesser extent), and AC power. If you start here, it may be a while before you surface. He has collaborated with Robert White on several of the speaker projects on his site. He is an excellent teacher and sells high quality printed circuit boards for many of his projects. His no nonsense attitude has appealed to me since my first visit to his site back in 2003.
Siegfried Linkwitz is a bit of a legend (as in the Linkwitz-Riley crossover), his extensive web site is focused on dipole speakers, but he has also extensively documented his active crossover designs and his thoughts on sound recording and reproduction. Mr. Linkwitz is from the group of people responsible for the incredible technical products produced by Hewlett Packard from the 1960s through the 90s.
http://www.silcom.com/~aludwig/contents.htm
Much of the content in Art Ludwig's site is beyond 99.9% of the people who will visit (including me). His site is probably one of the most in-depth system designs documented on the web. He started with a general knowledge of acoustics and deep experience with advanced electronics and derived the design formulas (seriously) we all use. Most of his math is still beyond me, but to follow his well documented system build is quite fun (he's another man from the old Hewlett Packard brain trust).
http://www.roger-russell.com/aboutmc.htm
Roger Russell's history of McIntosh. An accurate, bittersweet description of what has happened to an audio giant. Unfortunately, this isn't a lone incident. This appears to be a trend in industry everywhere. The loss of insight and informed guidance by strong leaders who understand the technical aspects of their products, as well as their customer's needs and expectations, seems to be coming to an end everywhere.
The Project May site is a bit scattered, and appears to have died. The rest of the site is a great look at the industry and Altec/JBL as they developed and the sound industry grew into its big years.
These sites are very interesting, and great sources of information.
http://www.audioheritage.org/html/perspectives/drews-clues/1-intro.html
Back in 1997, Drew Daniels designed this system for Disney. The details and results are there. An interesting look into pro-sound, and what it cost to achieve good results in medium sized venues back then. Many of his ideas can be scaled down and used in home systems.
John Krutke (zaph) has reviewed a huge selection of drivers on his site. His published system designs are widely accepted and appreciated by all. He is another man whose no nonsense attitude is greatly appreciated. He has designed speaker systems for both Parts Express and Madisound, and his first driver (!) design is sold by Madisound. It is an excellent 5" mid-bass driver that I use in my system in my study.
http://sites.google.com/site/undefinition/diy
Paul Carmody has put together what may be the most beginner-friendly site for speaker builders on the 'net. He's assembled a great collection of speakers and gives great pointers for beginners and experienced builders alike.
http://www.audioheuristics.org/default.htm
Mark K's pages with his driver tests and designs. Over time, I noticed conversations between Mark and John Krutke in the forums that led me to Mark's site, lots of driver information and good general information too.
All of the publications from the Audio Engineering Society are available in PDF form here. Membership dues are $99 + $135 for a one year subscription to the Electronic Library (free downloads of as many articles as you want). If your math skills extend to differential equations, Bode Plots, and filter math, this is where most of what we use today comes from. One of the coolest things I have seen here was Neville Thiele's and Richard Small's masterclass presentation at the 2008 AES Convention. This is a two hour video of the class as presented by Thiele and Small for a group of speaker designers, about using their parameters when designing driver enclosures.
http://www.rane.com/digi-dic.html
http://www.rane.com/library.html
The Rane technical library is an exceptional gathering of accurate information, all for free.
I'm a fan of forums, they are an excellent way to learn, they're great for getting questions answered (from noob level to complex issues). These are my favorites:
http://techtalk.parts-express.com/forumdisplay.php?f=2
My favorite forum. Look for:
Jeff Bagby (Jeff B.) http://www.salksound.com/speakers_archos.shtml (surf around there, he's involved in many of their designs and posts on their blog)
John Kreskovsky (johnk... pay no attention to his typing, he's a permanent member of the way-smart club) http://www.musicanddesign.com/index.html
John Krutke (jkrutke) http://www.zaphaudio.com/
John Murphy http://www.trueaudio.com/st_diff1.htm
Bill Fitzmaurice http://billfitzmaurice.net/
David Ralph (DLR) http://www.speakerdesign.net/
Paul Carmody (used to be undefinition) http://sites.google.com/site/undefinition/diy
Curt Campbell (curt c) http://speakerdesignworks.com/index_page_2.html
Dennis Murphy (framus) http://murphyblaster.com/content.php?f=main.html
Daryl (ignore his acidic personality, he's smart), Ben Schaffer (Wolf), Dan Neubecker (dlneubec), Dirk, Pete Schumacher, Andy Graddon (Andy_G), Marty Halfenbreadl (martyh), Bill Schneider (williamrschneider), shawn_a, Deward Hastings, Mark (WWWJD, great with electronics and speakers as well), and about a hundred others I'm leaving out. These guys are friendly and like to help. In the years I've been on this forum, I've learned a tremendous amount, just by watching (and occasionally stepping on my tongue).
http://www.htguide.com/forum/forumdisplay.php4?f=6
Look for Jon Marsh (jonmarsh), Brandon (augerpro), Jim Holtz, Jed Knuz (Jed) http://www.clearwaveloudspeaker.com/), Chris D'Alessio (CJD), Mark K, Dan Neubecker (dlneubec), Chuck (chasw98), . There are many others, Jon and Brandon are the ones I've followed recently.
http://www.diyaudio.com/forums/top/
A large forum with strong speaker sections and great amplifier sections. Look for Earl Geddes (gedlee) on speakers.
For Amps
http://www.diyaudio.com/forums/chip-amps/
Great learning source for basic construction techniques and ideas. This section of the forum is focused on chip-amps and is a great place to start. Look for Andrew T. (AndrewT), pacificblue, panson_hk, and Rainwulf (find his post on power supplies, it's great). I suspect the other amp sections here are just as good.
http://www.avsforum.com/avs-vb/showthread.php?t=855865
Chuck (chasw98) has also posted a great series of amplifier tests on the AVS forum. I like this series of tests, it puts things into perspective (he tests amplifiers under loaded conditions, using what appear to be hot water heater elements wired to create 2Ω, 4Ω, and 8Ω loads capable of handling 3.6 to 14 kW. Most of the amps he tests are designed for pro use in live venues and sub amps with big reputations. However the results are fun and useful to see, and they provide some good references and best-practice thoughts for good hi-fi power amplifier design. I do take many the responses to the tests with a grain of salt. Instead step back and think about what it will really take to make you happy with your system. Go watch some bar bands and find out what they're using to power the main PA, or check out some dance clubs' PA amps. Remember how loud it was? Will you play your music like that? Over 115 dB, constantly? If you will, go for it, but you may find that 100 to 400 watts of serious amplification, strategically placed in each channel (multi-way active speaker systems) will play loud enough to hurt you (and maybe your neighbors).
Jay R. Taylor
March 2010