Back in the early days of the House Jacks we had long late-night discussions about what we should and shouldn't be, and what was and wasn't a cappella.
I argued (successfully) for the use of distortion on Naked Noise, and I produced Code Red, for which the Beelzebubs (again?) took heat for destroying a cappella.
In short, I'm no stranger to controversy, and I have no interest in limiting the boundaries of a cappella. Make great music however you can.
However, there is one topic on which I might appear antediluvian, and that's the use of effects pedals in a live show. You'd think the House Jacks would have been early adopters, but we have always avoided using effects. Moreover, I usually cringe when I hear them, and by usually I mean almost always.
1) The magic is gone: There's something special and powerful and almost spiritual about the sound of the human voice in harmony. Moreover, there's something amazing in the depth and breadth of the timbres that can be created by groups nowadays. Vocal percussion alone is stunning to all but the most jaded audience member, and increasingly groups are finding more realistic tones in their background textures, weaving in electric bass, a horn section, distorted guitars, etc. All created entirely vocally.
As soon as you introduce an obvious on-stage effect, you've signaled to the audience that it's not only you making the sounds. Plus, you call into question all of the sounds you're already making. You can argue all day that it's only 5% of your sound, but that won't be the impression you leave. You're man plus machine.
2) Live and studio are two different things: Your live show does not need to sound like your studio album. In fact, it probably shouldn't. They're two different things, and I personally hate going to hear a band, and then getting a replica of the album. I could have stayed home and saved money.
There is a reason that studio albums are enhanced: the sights, smells, ambiance of a live show is impossible to capture in digital audio bits, so much more is added to fill out the sound and round the edges off things that would never bother someone live, but stick out as imperfections under repeated listenings. You don't need your live show to be as perfect, as it's something different, and ultimately the connection between audience and performer, the message and mood of your music, is much more important than specific frequencies.
Your CD might need to hold up to other instrumental pop music when in shuffle mode, but live you control everything. A black and white photo might look out of place in a gallery of color photos, but you don't look at a collection of black and white photos and think "if only that rose were red..."
3) They sound bad: Perhaps my opinion would be different if the technology were better, but the fact remains, to my ear, that pedals sound lousy. Octave pedals sound artificial, digital, soulless, monochromatic. They have a brittle quality, casting unbalanced overtones, which clash against a group's blend. The best option remains to only favor the core pitch, and have it mixed quietly under the live bass note, but even then it's angular, obvious.
And a distortion pedal? It's like one of those tacky colorized black and white photos where everything is black and white except the red rose in the middle. It's like it's the worst of both worlds, to my taste: either give me a color photo, or a black and white one, because this mixed image looks artificial, jarring, amateur.
4) People staring at their feet: I love getting lost in the music, lost in the moment, and that is broken as soon as your singers go from emotive extroversion into studio musicians twiddling with knobs, looking down and stomping on an errant cockroach. It's as if they shift from "I'm sharing this piece of my heart" to "I'm producing sounds," and makes me wonder why they didn't just bring along a guitar or synth. In short, it's very difficult to make it transparent, and effortless,
5) They're cold. This is rather ineffable, but people are warm, machines cold, sonically, experientially. One of a cappella's greatest assets is it's warmth, in the face of so much artificiality and mechanization in current music.
6) People generally hate, or at least disrespect alteration. The term "autotune" is used with derision, even if it's not understood. Plastic surgery is looked down on by most, especially if it's apparent. Photo retouching, artificial ingredients... people prefer the honest and natural, especially if given a choice. Signal to the audience that you're enhanced, and they'll like you less. That's human nature, or at least current Western culture.
All this said, I'm not hoisting a flag with the words "never use pedals!" Instead, I'm cautioning people against using them unless they're certain the benefits outweigh the detractions. The response I usually get is along the lines of "but it sounds better," to which I reply "but your performance is not just about approaching the sound of instruments. If it is, why not just use instruments?"
Seriously. I'm not at all against instruments. I love them, and in fact my grand piano and assortment of guitars crowd our living room. What I'm saying is this: a cappella has never been and will never be about replicating instruments. If you think it is, then you have lost your way. Music is communication, and I sure hope you're trying to say something more than "look at me! I sound like a guitar!" because that's nothing more than a parlor trick that gets old quickly.
Novelty acts have their place, but great a cappella is not a novelty act, and in fact we've spent a great deal of effort over the past 20 years proving that point. Perhaps I can draw an analogy:
Imagine two solo musicians, both with live looping rigs. One is tricked out with loads of effects, and has a series of moments where he shows off all the cool sounds he can make. Lots of fun. The other uses her rig almost secondarily, like KT Tunstall does when performing "Black Horse and the Cherry Tree" live. It's not about the effects, it's about the song, and what a great song it is. The novelty of her voice layered gives way to a strong mood, a moment she carefully crafts in which she takes you on a trip through her image filled story, feet tapping all the way.
At the end of the night, I suspect you'll maybe tell a friend about the first musician, but likely not return to that show. You saw it, you got the point. However, with the second, you'll likely buy the album, join the mailing list.
Now, I can't tell you to be the second kind of artist, because every single person I've disagreed with over this topic would swear they are. And yet I think the pedals are likely getting in the way of their music more than enhancing it.
In summary: be less worried about how you sound and more worried about what you're saying. If your pedals don't disappear... vanish as your audience is lost in your music, then maybe you should make them disappear.