The Plangent Process for Retrieving Everything from Analog Tapes
Recorded on September 28th, 2016
A few years ago I ran across this article in Tape Op about something called the Plangent Process, a crazy and elegant method of harvesting the rock-steady ultrasonic bias signal originally recorded on an analog tape and using it as a wow and flutter correction signal. If you can capture the reproduced bias tone and measure how far off it is at every instant of playback, you can do some insane math to realign the audio signal in time and get an eerily steady playback from something that was purely analog before. Wow and flutter are effectively gone. That’s what Plangent Processes does with proprietary wideband tape heads and preamps and some fancy FM DSP. Once you grasp it, it seems so obvious that you wish you’d thought of it.
There are a crapload of ear-opening example clips, if you can get past the tiny text and cramped layout. Actually, not just ear-opening but shockingly great. Besides the obvious immediate advantages of removing wow and flutter distortions introduced by stretched tape or inexact tape transports, the Plangent Process restores high-frequency sounds that were just smeared and absent before. All the claims you read about space around the instruments and a solid sound-stage are 100% true. The Bruce Springsteen “Born to Run” 30th anniversary remasters used Plangent and they sound incredible.
In fact, it’s so good that it makes me wonder if it could be too much of a good thing if applied to some older rock records that are already deemed “good enough”. Maybe “Immigrant Song” would be even more impressive if run through this setup, or maybe it would be robbed of its heft — I don’t know. But it sure is fun to play through all those samples and hear the before and after.