Sorry for the late reply, completely missed these questions.Hi does the pro mic have SPL calibration?
If not how can I do it without a SPL meter?
Can I do it like this link http://johnr.hifizine.com/2013/03/room-eq-wizard-spl-calibration-without-an-slm/
Also is the XLR cable balanced or unbalanced?
The only ways of calibrations I have experience of is using a specific calibrator or the use of an extra SPL meter. The use of an extra SPL meter is probably the easiest way and less expensive.
I have used this B&K calibrator, but it's crazy expensive.
Here is an alternative for a cheaper version, do not know if it is available worldwide or only in Europe. There has to be other similar options.
The signal is unbalanced, but XLR because the microphone requires some low voltage (not really phantom power).
Do not forget to add the calibration file to adjust for the frequency response.