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Mixing Bass and Drums with Sound Radix Auto-Align


Matthew Weiss here —,, and of course,

Now, I’m going to do a quick demo of a program called Auto-Align. It’s by a company called Sound Radix, which I’ve said many times, is one of my favorite plug-in manufacturer companies, and what Auto-Align does, is when you have two things that have similar material in terms of the sound – like a kick drum that’s recorded with two mics, for example – those mics are a distance apart.

The waveforms do not come in perfectly in-phase. They come in slightly out of time. Sometimes that timing difference is a good thing, sometimes that timing difference causes phase cancellation, which results in a thinner or tonally disproportionate sound that we don’t necessarily like.

So, what I’m going to do is I’m going to remove my instances of Auto-Align here, and play it. Then I’m going to bring them back on in.


Notice that the sound gets much fuller, much punchier, and just springs to life right away when I have Auto-Align in. That’s because phase, it’s one of those things that we hate to think about because it’s such a technical idea, but it’s so crucial to how the sound translates. Getting the overheads to be aligned is really important for getting our stereo image to sit the way we want, and here down here, I have a couple of bass recordings of DI and an amp that were not perfectly in time.

Now, all of this I actually recorded myself. This is not something I got in to mix, this is something I did for, and actually, that whole process was recorded, in case you want to hear me doing some stuff live in the studio, but that’s just an aside.
So, I got things pretty close, because I’m a pretty good engineer, I like to believe. But that said, sometimes things aren’t perfect. For example, the right overhead was coming in 25 samples – Ha, seconds… 25 samples early, versus the left overhead, which in translation, ends up being something like three inches of difference, more-or-less. It’s very slight offset. You know, had to flip the snare bottom phase. That’s fairly normal, and I think that was off by maybe 15 samples.

Yeah, the snare bottom was off by 15 samples, which, you know, again, that’s like, just the tiniest bit of distance. Otherwise, it was right in there, and the bass, if you check this out, this is one of these places where, like, using an Auto-Align plug-in I think is absolutely crucial is the bass.

This waveform is not totally properly showing, but you can see there’s a slight offset. Here’s where this is hitting it’s null point, and this is hitting the null point just before hand. That’s because I have a slight air gap in between the microphone and the bass cabinet, and the DI is direct, so there’s zero timing difference between the direct signal and where it hits the tape, or where it hits the computer, and there’s a very tiny timing difference in terms of the amp.

So, I aligned the DI signal, which was 35 samples too early, and by the way, just to give you an idea of how close that is, here, I’m super zoomed in, and you can see that the difference is very, very slight. So, just to tell you how close it was to begin with, but even just adding up these little tiny differences in timing and phase, all-in-all, it does make a profound difference at the end of the day.

It’s a bunch of slight differences that really add up, and if you’ve seen my other tutorials, you know I’m really big on slight differences that add up, because that’s a crucial part of getting the mix to retain the original tracking intention, but making it sound better than it could have.

Matthew Weiss

Matthew Weiss

Matthew Weiss is a Grammy nominated and Spellemann Award winning audio engineer from Philadelphia. Matthew has mixed songs for Snoop, Sonny Digital, Gorilla Zoe, Uri Caine, Dizzee Rascal, Arrested Development, 9th Wonder, !llmind & more. Get in touch:

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