The recording and mixing engineers at Tamla Motown Hit Factory studios in the 60’s and 70’s used a special technique to get maximum punch into their mixes without squashing the dynamic life out of it. (as is so prevalent in today’s music)
The trick is to make the mix “sound” louder, by using compression. Radio stations have used compression for 50 years or more to “boost” the loudness of their transmitted signal. In the early days of “pirate radio” in New Zealand the transmitters on Radio Hauraki’s ship “Tiri”, were low powered and so had a limited signal reach. In order to extend that reach they compressed the signal extensively; and it worked well. The Hauraki “sound” off air was heavily compressed.
But an over-compressed mix is NOT the way to present a song master to the manufacturer of any carrier if you want it to stand up as a great-sounding track when played through a good stereo Hi Fi system. Motown engineers recognised this fact and strove to strike the perfect balance between compressed “impact” and yet still retain the dynamic feel of the music. They also knew that radio would be adding further compression when broadcast, so they did not want to over-do it.
This technique has been copied by many professional producers and engineers over the years, but from what I hear on radio and online streaming most of the recordings suffer from constant over-compression. I call it “Dynamic Boredom”. It sounds as though every instrument was compressed individually, and then on top of that, the entire mix got squashed to make it SO loud….and in the process became the same from start to finish, with no light and shade. It sounds like a black and white picture. By retaining some of the musical dynamics you get all of the colours of the audio spectrum, so to speak; including depth of field for free.
This is the trick; sometimes called Parallel Compression mixing.
Firstly, Motown seldom used compression when laying tracks to the multi-track. If some compression was required on vocals, it was a subtle smoothing out of the peaks; nothing more. Perhaps the same on the bass guitar.
Then, when time to remix they would patch the LR mix to TWO stereo buses, The main mix buss plus a sub-mix buss. Then put a carefully selected stereo compressor across the sub-mix stereo buss that was brought up on a pair of faders to be ADDED to the uncompressed mix as required. The compressed signal was NEVER monitored at all whilst working on getting the mix together. Once the mix was considered to be right, then the compressed buss was gradually mixed in with the uncompressed mix to add punch without destroying the original feel of dynamics.
This is virtually the same technique as Parallel EQ, or Parallel micing, (DI plus mic on guitar or bass)
It means simply mixing two signals together, from the same basic source, one of them processed, the other unprocessed. Try it… you’ll like it!