The latest generation of sonic vibration machines are digital, not analog like the older ones that gave off so much heat.
The Sonic Life vibration machines have a speaker under the plate unlike the other type that has the speaker in the rail, but those are way more expensive, like 4 times as much as the Sonic Life Personal.
The newer digital sonic models have much lower EMF than the analog models they had years ago under the plate. The Sonic models have the smoothness of a pivotal machine and the linear power of a Vibeplate. For those that like the gentleness of a Zaaz 20k (you can go try one at Costco or Sam's club). The sonic models are super gentle and have nearly all the ballistic impact taken out.
With the Sonic Life models you don't have to turn it off before stepping off like the older generation models. They use to shut off when the machine sensed there was no weight on the plate. The latest models are only around 100 pounds and are very light compared to the older ones.
Although they are more gentle, they move work the lymphatic system less than mechanical types but for people who have severe issues where they can't handle any ballistic impact, this might be the only one that they can move up and down on. The Vibeplate and the Sonic Life are my two favorites for people with back issues. Both types are good in their own ways as they have the least ballistic impact of any linear machine. One type I like the most for bone density and the other for lymph drainage. I still like the high amplitude pivotal types the best for lymphatic drainage as long as someone doesn't have any back problems. For those who can't afford a sonic type and need something with low ballistic impact, the Vibeplate and Zaaz 20k are my two favorites.
If you are interested in a sonic machine or a machine with ultra low ballistic impact without jarring, let me know on my vibration quiz.