Dave Dameron said: In the manual I have each amplifier has a 12AX7 and a 6BQ7A twin triode plus a 6BH6. I'm sure we can work something out. I've being searching for a first born child (boy or girl) for a completely unrelated hobby. OR you could just keep me up to date on your music experiments. Keep in mind that this Operations Manual has theory but no example programs. It's the EC-1 Operations Manual that has the example programs. A good source for magazine articles on analog computers is the American Journal of Physics. Including one article on replacing the Heath ES-201 amplifiers with 741 op-amps. They have a searchable index on the web. And I found the issues at the S.F. Public Library (other libraries may differ). Other magazine called "Simulation" in their Febuary 1997 issue had an article on simulating an analog computer in Excel. Which looks like a great way to "single step" your program before moving to the computer. (See Windows does have a use) :) Speaking of computer music generated by old machines, if you don't already have a copy, I recommend "Music by Computer", John Wiley and Sons, 1969, 139 pages. This book was started from papers submitted to the "Computers in Music" session at the 1966 Fall Joint Computer Conference in San Francisco. In a pocket in the back cover is four 7" floppy records with a total of 8 sides, containing examples of computer generated music and sounds samples to accompany each paper. I don't think I've seen this article. (hint) :) Regards, --Doug ========================================= Doug Coward Press Start Inc. Sunnyvale,CA =========================================