Dr. Seuss got it right in 1955: “If you stay home with Zebra, you’re stuck in a rut. But on beyond Zebra, you’re anything but.”

On Beyond Zebra! was never one of Dr. Seuss’s bestsellers, but it was my childhood fave. I loved its premise that the alphabet could extend past the letter Z, and that only our lack of imagination confines us to the usual 26 characters. Sure, we need A, B, and C to communicate, but we can dream in Yuzz, Fuddle, and Zatz.

I flashed on that kindergarten Gnosticism decades later when I started learning about digital audio. Once you get an inkling of its power, you start wondering whether many aspects of traditional analog tone are popular because they’re great, or because they’re traditional.

Both, obviously. I’m simply suggesting that it’s good to question our analog assumptions. Take tubes and distortion, for example.

Are Tubes for Rubes?
No—it’s just a rhyme, silly! Tubes are awesome. But guitarists of my generation were reared on tube dogma. As a young guitarist I was told over and over that only tube distortion mattered. Sometimes it was expressed in emotional terms. (“Nothing else has that feeling.”) Sometimes it was aesthetic. (“Only tubes sound warm and musical.”) Sometimes it was quasi-scientific. (“Only tubes produce desirable even-order harmonics.”)

Like sulphuric acid, digital distortion eats through almost anything, so it can be a great choice for dense passages of aggressive music.

The attitude was so prevalent that manufacturers would often employ tubes in stompboxes in ways that had no audible effect, successfully duping many tubaholic guitarists. (Electro-Harmonix even went so far as to add a purely cosmetic LED to some pedals, oriented to shine up through the glass bottle to reassure players that their “tube tone” was smokin’ hot.)

That ironclad attitude eventually softened a bit after being challenged on two fronts. On the tech side, tube emulations improved to the point that most listeners—and frankly, most guitarists—can’t tell the difference, at least on recordings. Meanwhile, extreme and experimental music genres challenged old ideas of “good” distortion. Just when tubes were no longer the only way to get “that sound,” a significant number of musicians stopped giving a crap about “that sound” in the first place.

Now, I don’t want to get sidetracked into another anarchic amps-versus-models debate, but given that—oh, hell, who am I kidding? I’m always up for an anarchic debate! Examples 1a through 1h are recordings I made of classic amps alongside modeled versions from the Amp Designer plug-in in Apple’s Logic Pro. Can you tell which are which?

I posted a version of this test on my blog a few years ago as a contest. Hundreds of players competed, but only three nailed the answers, and some did so using a trick of sorts. (If you listen to the tail end of each clip on headphones, you can sometimes hear amp noise as the last notes fade away.)

Yeah, there is a difference, and I don't doubt that a small percentage of listeners can discern it. But on the "Things That Matter" list, it's somewhere around #97. So let’s proceed on the assumption that the recording guitarist can use amps or models to equally fine effect, shall we?

Not Found in Nature
The conversation gets more interesting when you ditch comparisons and explore the ways uniquely digital sounds can contribute to a recording. I threw together a musical example, using drum tracks swiped from my frequent musical partner Dawn Richardson. There are five guitar parts: a doubled riff in the A section, a thin-sounding counterpoint line, and a more distorted doubled riff in the B section. Plus bass.

I simultaneously recorded directly and via miked amps. I made “obvious” amp choices: For the first doubled part, I cranked a vintage Fender Tremolux to mild distortion, but employed a chunky Marshall combo for the B section riffs. For the high, thin part, I ran a homemade octave fuzz through a small Divided by 13 combo. Ex. 2a is the band track. Ex. 2b is the guitars alone, and Ex. 2c is rhythm section alone. (Pardon my lazy-ass rough mixes.)

There’s nothing offensive about the guitar sounds in Ex. 2a—and that’s the problem! They’re generic. Yeah, I could make them pop more via EQ, compression, and micro-edits, but we’d probably still be nodding off.