Calibrating

I was in the process of rebuilding my studio desk when it occurred to me that the slight change in height would affect the acoustics of the room.

“Well,” I thought. That means remeasuring everything. And an excuse to get a new measurement microphone.

I looked about and basically by accident stumbled across Sonarworks. They’re known for making headphone calibration software, and have recently begun a foray into monitor calibration. One of their packages was a demo, which came with a rather decent measurement mic, for a whopping $40.

What the heck -a cheap, decent measurement mic, and I can demo the software and see what it has to say about my room. Worst case, I end up with a measurement mic.

Okay, it ended up being a little less cheap than I expected, since the microphone shipped Fedex from freaking Latvia, so shipping charges were a bit much, but I was still ahead of the game. The mic arrived a few days later and I put it through its paces with Fuzzmeasure and REQWizard. Got some decent readings, noted a few trouble spots that I’ve always had near my crossover points and along a hard-to-trap z-axial node/null. I made a few adjustments to my subwoofer crossover point and levels, and got some improvement.

I’ve always been skeptical of room-correction/speaker-correction software. No matter how much fancy math one does, the cold hard translation to physical reality often gets in the way of idealized imrpovements.

But that didn’t stop me from firing up their “Reference” software demo.  Just to try it.

I am impressed.

Not without caveats, of course – I can imagine this working best in a treated environment and with rather good speakers, since it has to do a lot fewer crazy adjustments if we’re only talking about a few dBs here or there.  No speaker adjustment is going to adequately compensate for poor RT60 or flutter echo. Oh, and the documentation could be better.

The sampling process is pretty straightforward. You run the wizard, it chirps and sweeps from the speakers, and it makes adjuestments based on where the mic is at various points. It’s…distrubingly good at it, too. It guessed my monitor separation as being 3’11 inches. “That can’t be, I put my stands 4′ 6″ away from each other!” I got out my tape measure and…3′ 11″. Apparently all my turning and toeing and adjusting had cut 3″ from the distance on either side. So that was impressive. It also was able to quantify something I had noticed but couldn’t put my finger on – that one of my monitors was balanced slightly (1.5decibels) louder than the other. I went back and adjusted my monitor trim and a lot of stuff evened out sort of magically.

I re-measured, re-sampled, and then fired up the compensation plugin on a remix I’d been working on. The differences were subtle, but notable. My soundstage was deeper, my “sweet spot” was wider, and the detail on my recording was clearer. It’s easy to attribute this to some sort of crazy magic, but it seems like a pretty simple compensation – if my low-mid is too loud at certain points, that mud is going to obscure a lot. If I have a null at 140hz, I’m losing out on frequencies I should be hearing. Same with any phase adjustments affecting my stereo imaging – poor phasing can cancel out stereo information.

It is, however, fussy. I was moving some cables around and knocked a speaker out of place. I put it back without resampling/recalibrating, went back into my mix, and there were audible phase problems. I ran a re-calibration and everything went back to working fine. So it’s something I’ll have to be aware of. There are also strong level differences between calibrated and uncalibrated signals, even with the trim engaged and turned up the calibrated was still quieter than the raw signal. It’s not much of a problem, it just means I need to re-adjust my output levels for K-metering (and get better at using the plugin’s internal bypass instead of the DAW master bypass). Latency is also an issue in higher quality modes, and as is often the problem when using linear phase modes, there can be pre-ringing in low frequencies.

So, the big question is, though…does it help? I would assert that yes, it does. On the few mixes I’ve done with the demo, my first-pass output has been cleaner and more translate-able than those mixes I’ve done without it. Taking mixes to do the “car test” has been dramatic – usually I find myself going back and doing endless fiddling with the low end to try and get it to sit right in the mix, but both times everything came back clean on the first try. I’d love to ascribe the improvement to my mixing skills levelling up in some way, but I didn’t do anything different than usual, so it’s much more likely that being able to hear better was simply the ticket.

This is by no means comprehensive. I will continue to see how this works (I’m more than willing to pull the trigger on a purchase when my demo expires) and perhaps try multiple calibration tests to see if the results are similar each time. This really doesn’t speak to any of the other room correction applications on the market (IK ARC2, KRK ERGO, etc), merely a single instance of SonarWorks reference in a reasonably stable, treated environment. So mileage may vary, naturally. But dang, it seems to work much better than I expected.