The tech behind the music part two: Virtualization

In my last post, I talked about how the shift from analog to digital tools revolutionized the way we can edit audio, and how we’ve been able to “virtualize” expensive audio gear, like compressors, into much more affordable plugins.

But this is only where virtualization starts to get interesting. Now that we’re able to create a digital model of a piece of gear, how about an entire room?

Wouldn’t it be interesting to record at the Notre Dame Cathedral? No problem! Just pick up a "convolution" reverb (digital audio workstations, or DAWs, are starting to come standard with these — Logic has one), and find yourself an IR (impulse-response) file for it, such as this one.

Impulse Responses are basically created by someone who stands in the real space and fires off an audio sweep that runs from a really low to a really high frequency. You can see the sweep in action here (it sounds terrible):

They then record how this sweep sounds from various spots in the room. Subtract the sweep from the recorded signal and voila! You've recorded the sound of the room itself.

One really interesting benefit of technology like IRs is that, it not only makes quality more economical, but it also opens up new areas of experimentation. For example, it's now possible to create the sound of a grand piano played inside of a glass bottle.

Virtual amp modelling

But wait, we’re not done! Wouldn’t it be great if you could virtualize the gear, an awesome space and even the expertise of a great recording engineer, all at once? That's what guitar amp simulation plugins are now doing. Here's an example of how guitars are traditionally recorded:

Believe it or not, placing a microphone in front of a guitar amp is still the default method in many major studios.

In theory, though, you should be able to model the sound of that mic, the speaker of the amp, and the way they interact in a room at various distances. And this is exactly what modern guitar amp simulators do. Here's an example of using a virtual microphone to record a virtual guitar amp:

Mo technology, mo problems

Ackerman Music blog studio2Many people will argue that, if you know what you're doing, you'll get a way better sound doing it the old fashioned way. And they may still be right. But that gap in quality is getting smaller and smaller. For someone like me, who records in my apartment living room, and doesn't have access to expensive amplifiers, there's no question of which system I prefer. I can record the sound of a vintage tube mic two feet away from a wall of speakers topped by a Marshall amp head cranked to 11, and it won’t result in a single noise complaint from my neighbors. (Oh, and most DAWs come standard with pretty decent guitar amp simulators these days too.)

Virtualizing not only allows you to capture a magical place or piece of equipment, but it actually makes those things more flexible. Just think: when you're using real hardware, if you come back to work on a piece of music after a month spent working on other music, you have to turn all the dials back to the settings you had before. Or you have to remember where you placed all of those mics to get that awesome room sound. That's a lot to keep track of. But those problems go away with software.

One unexpected downside is that decisions that used to be made early on tend to get pushed to later in the process. You used to have to commit to a certain guitar sound. Now, you can be changing your amp right up to the final mixing stage. This abundance of choice and ability to constantly tweak can be paralyzing if you let it get out of hand. It also risks losing some of the magic of making music. It's telling that some of the most popular plugins and hardware are all about adding noise back into the signal (noise we worked so hard to get rid of!). There are many emulations (such as the Kramer Master Tape) that will make your pristine digital audio sound like it was recorded on not-so-pristine tape. Limitations can spark creativity. So now that I can create any sound I could possibly imagine (and many that I can’t!), I find myself inventing limitations to produce better material.

Virtual performers

It might make a lot of musicians more comfortable if virtualization of the studio stopped here, but there’s one more thing we’re now able to model: musicians themselves. In some areas, this is still fairly rudimentary. I have yet to see acoustic guitar virtual strumming or virtual vocals that have impressed me much. But with something like the drums, you can get some very realistic “performances” without having to touch a set of sticks.

For a long while, the focus has been on modelling all of the nuances of “playing” a drum kit in a type of synthesizer called a “sampler”. This allows the drum hits to be triggered by MIDI (overly simplified, this is a protocol that allows you to say, “play this note at this time with this velocity”), but requires you to still know enough about drumming to program a realistic performance. More recently, plugins have been taking things a step further. Logic Pro X’s Drummer, for example, allows you to create some very complex drumming performances with just a few parameters:

No, this can’t beat a real drummer. In fact, using a computer drummer can make you appreciate just how much a great human drummer adds to a song. But the computer can get you close, and if you’ve worked with a few real drummers before, you can often make your own edits and end up with the best of both worlds. And again, when you’re recording in an apartment, the advantages of the virtual world quickly start to outweigh the advantages of the real thing.

“How terrible! It’s only a matter of time before no one has to play an instrument any more! What’s going to happen to real music?” Well, I’m not too worried. It’ll be a while before computers can be as exciting and emotionally engaging as a real band on stage. And nothing prevents anyone from using older methods of producing music. But it also opens music up to a whole new group of people. If you’ve got a good sense of melody or just great taste, but don’t know how to play an instrument, you can now create compelling compositions on your own. Given how art constantly feeds off of other art (I’m starting to see many rock bands adopt elements from electronic music these days), we should only look forward to more people making their own music.

How to get started

Do you want to take a stab at this yourself? Well, you're in luck, because at-home music production has never been cheaper. Logic Pro is only $200 and has pretty good versions of almost everything I've talked about. Garage Band comes free with most Macs these days, and offers a lot of the same basic concepts. Reaper is open source software you can get for free. I haven't used it, but I hear a lot of great things about it.

After you’ve grabbed some software, head over to a site like the Recording Revolution. Along with a lot of good, basic knowledge, this website is passionate about teaching you how to do more with less. If you're starting out as a complete novice, Coursera has a good (and free!) course to show you the ropes. Amazon also has some great books on the subject. "Mixing Secrets for the Small Studio" and "Zen and the Art of Mixing" are two I recommend. is a great resource for anyone wanting to dive into one of their DAW software packages (they cover at least Logic, Cubase, ProTools, and Reaper). And last, but certainly not least, YouTube is full of pros and amateurs alike freely demonstrating their techniques.

What happens when you make something amazing and want others to hear it? Don’t worry about getting that record deal (if you’ve read much about the “deals” many bands get, you might not want one). A site like can post all the music you want on iTunes for $20/year. Often when we think about technology and music, we think about the challenge of easy file sharing for bands looking to make a living off their music. I like to point out that technology has also done a lot to empower bands, and it’s helped bring about an explosion of great quality, innovative music. If you’ve got a great tune in your head, you now have easy access to all the tools you needed to make it and get it out to the world. These are exciting times for musicians and music lovers alike!