Warm up time for record playing

Yep, the rubber suspension in the cartridge, the bearings and motor for the tt, these all need to find "steady state" and one side of an LP does it.

Thanks,  I appreciate all the responses.

One lp side is a general rule. It's still dependent on room temp.

Others have stated that it’s the time your ears/whatever take to adjust. Makes sense on a certain level, and I agree your ears probably do need some time to adjust to volume levels being projected at you in your listening room vs what your ears have been processing throughout the day prior. BUT, I have the same experience with my analog rig in regards to warm up period. I will put a record on and leave the room and come back only to flip sides. After a couple LPs I come back and start really listening. I can hear an improvement vs when I start listening without a warmup. I wasn’t there listening throughout the whole warmup period so that rules out the theory of my ears adjusting. It’s cartridge suspension, TT motor, whatever it is, is warming up. That’s been my experience. 

Yup, it's the cartridge suspension alright.
Agree one LP side is about right.

Back in the day we used to aim a tungsten bulbed desk light with a reflector just above the cart to warm it up quicker.  Can't get those any more.