[ZVX-8 Qts published not matching calculated]

I know it is derived. You can use the published Qts and let the software define Qms or Qes, or use published Qms and Qes to define Qts. All get vastly different responses.

Am I the first person to put this information into a calculator? How did they come up with the recommended box sizes?

Guess I have to clean up my work station until I find my little DSO.

[ZVX-8 Qts published not matching calculated]

Hi, I just picked up a ZVX8-D4, it will be here Monday. I'm working on modelling a box. I've tried 2 versions of WinISD and Speakerboxlite, both give me a different calculated Qts than the published. Is this normal? Am I doing something wrong?

2Ohm
Published: FS 41.8Hz, Qms 3.6, Qes 1.25, Qts 0.76
Qts calculated: 0.928


4Ohm
Published: FS 40.0Hz, Qms 7.60, Qes 1.15, Qts 0.72
Qts calculated: 0.999