I did find another error in the formulas and fixed it. I also added the other 2 resistor network.
The latest is available here as always: http://robrobinette.com/images/Audio/Headphone_Resistor_Network_Calculator.xls
Ignore my previous post.
Most of the time I was using my work computer, which uses Excel.
Last night I used my home computer, which uses an Excel knock-off. It couldn't handle some of the formulas and I got wierd results! Bah! POS!
Just did a re-check with REAL Excel, works quite nicely!
Nice work, BTW!
Hopefully the fans will use it!
Edited by Chris J - 12/4/13 at 9:39am