Vocal Eliminator

Since the population of the world is now in hibernation, I thought I'd offer this free module to help you sing your way through it. The MRB Vocal Eliminator takes a prerecorded stereo track and attempts to eliminate the vocal. Some tracks definitely work better than others, but the random test samples seemed to work pretty well.

{INSTRUCTIONS}

Patch a pair of cables from the left and right channels of a stereo source to the IN L & R jacks of the module. The input recording must be stereo for the vocal elimination algorithm to work. This source can be the AUDIO IN from host jacks up top, or perhaps the stereo output from a sampler module. Patch the OUT jack to the L (mono) MAIN OUTS to listen to the result.

To adjust the 4 knobs for optimum performance, do the following.

Start the song playing and turn the MIX knob all the way to BASS. Adjust the BASS LPF knob as high as possible until you start to hear the vocal leaking through. A little leakage is fine and actually helps the fidelity of the final result.

Center the MIX and NULL knobs and continue listening. Most of the time having the NULL knob in the exact center is the right setting. Occasionally, moving it left or right a little will cancel the vocal better.

Adjust the MIX and VOCAL HPF knob to taste. Generally, having the VOCAL knob as low as possible is the goal.

{THEORY OF OPERATION}

This module uses a well-known method to eliminate vocals. It relies on the fact that most stereo recordings have the main vocal mixed dead center in mono. If one subtracts the right channel from the left (or vice versa), anything that is common to both channels will be canceled out, and any differences between the channels will be preserved. Unfortunately, the kick and bass are also mixed this way, so this module extracts the bass content using a variable 24db/octave lowpass filter and re-mixes it back in to the output. Most instruments, backup vocals and reverb are panned to one side or the other and will remain in the mix. The act of subtraction reduces the stereo recording to mono which is the reason there is only one output jack. Like mentioned above, performance is highly dependent on the track used. Some tracks work great, while others may sound a little phasy, and old Beatles recordings don't work at all because they panned everything to show off that newfangled invention, STEREO! Perhaps users will post names of songs that work particularly well (hint hint).

I hope this module helps you sing along with your favorite tunes to help lift your spirits during these trying times.

STAY HEALTHY EVERYONE and continue to make great music!