MUSICIAN, LIVE & STUDIO ENGINEER
Kildare / Dublin

Apr 21, 2016Sitting sounds into a mix using Maths.Posted In: mixing, delay, stereo ambience, steve albini, mix with the masters

Sometimes when mixing, you’re trying to make sure that all the different sounds are cutting through clearly and the nuances of the various performances aren’t getting lost. Other times though, the challenge is getting a particular sound to sit back into the mix, so it feels connected to the rest of the instrumentation, rather than sitting on top. A lot of the time it’s because that sound is too dry, maybe due to being recorded direct, and so the disconnect comes from it not feeling like it’s in the same space as the rest of the instruments. Here’s another technique I learned from Steve Albini which uses a multi-tap delay and good old-fashioned maths to create a stereo ambience effect that works brilliantly in that situation.

Steve used a hardware delay unit for this technique during our Mix with the Masters seminar, but I’ve done it in the box with great results.
You’ll need a stereo delay plugin where you can set up six discrete delays which alternate from left to right, with the distance between these delays growing according to a law. In the case Steve showed us, he used the powers of 1.3. You can use any seed number you like, you’re just using it to generate a sequence of numbers.

In this example:
1.3 to the power of 2 = 1.69
1.3 to the power of 3 = 2.197
1.3 to the power of 4 = 2.856
and so on…

You end up with a sequence like this:

1.69, 2.197, 2.856, 3.712, 4.824, 6.274, 8.157, 10.604, 13.78, etc…

Move the decimal point one place to the right and rounding the numbers to the nearest whole to get a new sequence:

17, 22, 29, 37, 48, 63, 82, 106, 138, etc…

Now pick 6 consecutive numbers from this sequence, say: 29, 37, 48, 63, 82, 106
Next, find the nearest prime number to each of these.
This gives a final sequence of: 29, 37, 47, 61, 83, 107.
Use these as your 6 delay times…because they’re prime numbers, they will never re-enforce each other by occurring at the same time.

Add this delay to a bus, send the track you want to sit back in the mix to that bus, and then use the bus fader to blend the amount of the delay effect to taste. As you slowly blend in the short ambience that this delay creates, the problem track will start to sound more like it’s in a space, and will merge back into the mix. You don’t want to hear the effect as a delay - a little goes a long way here.

Why does it work? In any room, you’re going to have 6 reflective surfaces - the four walls, the ceiling and the floor. The 6 delays here are faking the reflections of your sound source occurring in a stereo space. This is a far more subtle way of creating an ambience than using reverb. I’ve found it has worked particularly well on vocals, bass and synths…try it out!