As a first step (and also just as a learning exercise), I'd like to measure the T-S parameters of my particular pair of 201's.

I have all of the information I need to get started except:

How should I calculate a reasonable volume for the closed box I will use to measure Vas?

The Readme.txt file contained in PiAlign.zip says, "The test box should be 0.5 - 2.0 of the expected Vad, which can be
approximated using the ratio method described above."

I may be misreading the Readme.txt document somehow-- because I can't spot the ratio method for approximating the expected Vad. Can you help me out?

Thanks very much,

-uW

He showed that even though individual samples will vary somewhat due to the manufacturing process, this causes some of the T/S parameters to vary in such a way that in the end, the effects cancel out. In a given box, ported the same way, the woofers of a given model will perform very similarly even though Vas, Fs, etc may vary slightly.

He stated that what really mattered were the ratios of various T/S parameters. And even though T/S numbers varied from sample to sample, they varied in such a way that these ratios were the same.

Thanks for your patience,

-uW