user554: Not purely audio, but definitely related!
Jack Conte and Nataly Dawn have "pioneered" the 'videosong' format.

Rule 1 — What you see is what you hear. (No lip-syncing for instruments or voice)
Rule 2 — If you hear it, at some point you see it. (No hidden sounds)

Example — SEPTEMBER!!! by Earth Wind and Fire, 
Can anyone suggest how these are made? Preferably with freeware for Windows...

user1155: Their main software tools are Pro Tools for audio and Final Cut Pro for video editing, on MacBook Pro.  Here's Jack's list of gear:  http://jackconte.tumblr.com/Gear
Jack and Nataly gave a tutorial on making videosongs at CELLspace in San Francisco for the Disposable Film Festival a few months ago.  Unfortunately only the song performances afterward have been posted to Youtube so far.  Perhaps if you contact DFF you can track down someone with video of the tutorial and Q&A session.
Perhaps another tool will be able to meet your requirements.
http://en.wikipedia.org/wiki/Comparison_of_video_editing_software

554: <p>Not purely audio, but definitely related!</p>

<p>Jack Conte and Nataly Dawn have "pioneered" the 'videosong' format.</p>

<ul>
<li>Rule 1 — What you see is what you hear. (No lip-syncing for instruments or voice)</li>
<li>Rule 2 — If you hear it, at some point you see it. (No hidden sounds)</li>
</ul>

<p>Example — <a href="http://www.youtube.com/watch?v=xycnv87N_BU" rel="nofollow noreferrer">SEPTEMBER!!! by Earth Wind and Fire</a>, </p>

<p>Can anyone suggest how these are made? Preferably with freeware for Windows...</p>
 1155: <p>Their main software tools are Pro Tools for audio and Final Cut Pro for video editing, on MacBook Pro.  Here's Jack's list of gear:  <a href="http://jackconte.tumblr.com/Gear" rel="nofollow">http://jackconte.tumblr.com/Gear</a></p>

<p>Jack and Nataly gave a tutorial on making videosongs at CELLspace in San Francisco for the Disposable Film Festival a few months ago.  Unfortunately only the song performances afterward have been posted to Youtube so far.  Perhaps if you contact DFF you can track down someone with video of the tutorial and Q&amp;A session.</p>

<p>Perhaps another tool will be able to meet your requirements.<br>
<a href="http://en.wikipedia.org/wiki/Comparison_of_video_editing_software" rel="nofollow">http://en.wikipedia.org/wiki/Comparison_of_video_editing_software</a></p>
