Good (stereo) vibrations
When it comes to 1960s classics, there are few more memorable than Good Vibrations by the Beach Boys. But for many years, fans were destined to listen to the track in mono only. Stereo was out of reach.
Not any more - SFI-funded researcher Dr Derry Fitzgerald has cracked the puzzle of converting the track to stereo, and the technology he developed to do it could unlock several other early recordings and even help to boost home remixing and music education.
For a listener using headphones. a mono track sounds as though all of the sounds are in the ‘middle’, whereas stereo allows instruments or vocals to sound as though they are coming from the right or left, explains Dr Fitzgerald, who is a Stokes Lecturer at Dublin Institute of Technology. “With stereo you can get a much bigger sense of space in the recording,” he says.
Stereo became popular in the mid-1960s when consumers started buying stereo-enabled record players and hi-fi systems, but the Beach Boys still recorded the 1966 track Good Vibrations in mono. Part of this was down to the creative preferences of Brian Wilson, the group’s founder. “He is deaf in one ear and he just preferred to work in mono,” says Dr Fitzgerald, a life-long Beach Boys fan.
In the 1990s, computer audio technology made it possible to remix some of the Beach Boys tracks in stereo, but Good Vibrations was still lacking a certain something, he notes. “The tape with all the vocals on it is missing, so the sound engineers were stuck, they couldn’t remix the track in stereo.”
In his work at the Audio Research Group in DIT, Dr Fitzgerald realised the technology he was developing could get around the problem, by chopping up the vocals and instruments from the original mono track into separate signals that could then be remixed in stereo.
“I try and give the computer a mathematical model of what a musical instrument’s sound is in very broad terms - drums have different characteristics to voice, and piano and guitar are different again,”
he explains. “The computer uses the models to recognise the various instruments and vocals in the original recording and splits them out of it. Then because I have these little separate tracks I am able to mix those into stereo.”
He tried it out with Good Vibrations and sent it to the engineer who did the Beach Boys remastering, not expecting much of a response. But he had caught the right ear. “Much to my shock they asked me to remix some other songs,” recalls Dr Fitzgerald.
He ended up remixing several tracks in stereo for reissued Beach Boys albums, which brought him enormous fulfillment as a fan. Even Brian Wilson himself expressed his gratitude when Dr Fitzgerald met him backstage at a concert in Spain. “He said thanks very much for the work I had done,” recalls Dr Fitzgerald. “ He is not really in a position to appreciate it himself being deaf in one ear, but he had been told about it.”
The signal-splitting technology could also be applied to other mono recordings, and Dr Fitzgerald is now eyeing up tracks by the young Elvis Presley and Frank Sinatra, though even earlier tracks from the ’78’ era could benefit from the treatment.
The approach could also benefit home remixing of mono tracks and in music education, it would allow a particular instrument to be brought forward so a student can follow it more easily.
Meanwhile, for Dr Fitzgerald, the labour of love that was remixing Good Vibrations is a good memory; despite the intense involvement, he still holds it dear.
“It’s quite a computationally intensive process and it takes a lot of fine-tuning and tweaking to find the settings on the algorithms that work well for the song,” he says. “There were days when I would spend hours listening to the same 30-second snippet of Good Vibrations over and over again and I never got tired of it, which is a testament to the song.”