Hello Gabriel,
Is there a price difference between the Whest PS30.R and the PS30.RDT?
I totally agree on the Mint tractor. It is much more accurate than the Dr. Feickert universal protractor. IMO, it doesn't matter how much you spent on your analogue setup, the Mint tractor will bring a high level of accuracy to record playback.
The Dr. Fieckert Adjuts+ software is also amazing. It takes into account the value of level and phase angle to set up the azimuth. Before I got Adjust+, I used a test record for setting up the azimuth, by playing an azimuth dedicated tract with my phono preamp in mono, and rotating the headshell until the signal from the L and R channels get canceled.
The problem with this method is that, depending on the cartridge design, it's possible to have both L and R channels produce the same DB, but each channel could be out of phase in reference to the other. This condition produces undefined lower notes, muddy midrange and splashy highs. In other words, the sound is out of focus. With Adjust+, the phase angle of the L and R channels are set to match, even if, due to particular cartridge design, there is one channel producing +-DBs than the other channel. I went back and forth with both methods, and the sound with the Adjust+ is absolutely in focus. One I got acquainted with Adjust+, there is no going back.
Besides setting up correct azimuth, one can set the turntable speed much more accurate than with any strobe disc and light. Other measurements are wow & flutter, cartridge/tonearm resonance and cartridge frequency response.
Best,
iSanchez