Some of my latest Calculation tools are available on my publications page. These include:
Room Mode Calculator (both Imperial and Metric) with analysis and recommendations
Reflections, Boundaries, & Mass calculator. This can be a useful tool to sort out a design. I use it all the time.
Absorption Coefficients - not a calculator, but an organized list of data on many products. - PLEASE let me know if you have more data that could be included. - Especially GFR data. Thanks.
Download whatever you need and ENJOY. If you have any questions, please post them here.