Been testing out turntables, and because I had a Technics with a strobe, I'm obsessed with checking the speed. My Technics started straying with the strobe and I could hear the difference. So I bought a tachometer to check the speed on the turntables I'm testing. Now the problem is what is the proper way to test the speed. For example, I was checking the speed with a record playing. If the speed is at 33.3 during the middle part of a record, the beginning part will be 33.2, then it will transition from 33.2 to 33.3 for the middle part of the record, then transition from 33.3 to 33.4 for the remaining third of the vinyl side. When the tonearm IS NOT on the record, the speed will run at 33.5. So I see others testing with their phone, which will put weight on the platter, or testing with a stroboscope, which won't have the tonearm on the record. So the question is what is the proper method to test turntable speed? With a record on or off the platter? With the tone arm on the vinyl or off the vinyl? Do you test with the album off and tone arm off and assume that the weight of the vinyl and tone arm are part of the calculation of the proper turntable speed? I'm going to copy the vinyl to my hard drive and compare a digital copy to the vinyl for proper speed. That will get me as close as possible I guess. But putting this out here for opinions. Thanks.