any info on Petroff Labs full range speakers?

It looks like W. Edward Johansen ran Petroff. You may want to email Mama Jazz? Maybe W. Edward Johansen would be willing to answer your questions.

Petroff Audio Labs / Petroff Audio Research is creation of one Michael Petroff. I worked for Mike back in the late 80's building very elaborate home systems. I cannot recall where we sourced the drivers, but they were custom made. Later we started our own line of tube subwoofers for the car audio market under the company IntegralAudio. Mike also sold several analog circuit patents (mostly to control stage/imaging) to Harmon Int'l/JBL et al.

You have a very early set. Hope you enjoy them.

Hi there, I’m the son of the owner of this long-since gone company. He passed away in January of 2023. My father was not run by a man named ’W. Edward Johansen.’ If there ever was a relationship with such a person he would have been an investor or partner. My dad never had people above him for any of these businesses. As for the drivers I don’t know about PL but Magnitude Acoustics he used Atomic which is still around.