Line 6 KB37 Toneport

I like anything that simplifies my life, hence this review of the KB37. It’s a USB 1.1 audio/MIDI interface with one instrument in, two line ins, two XLR mic ins (with phantom power), and a 3-octave keyboard. In terms of controllers, it has pitchbend, mod wheel, five transport buttons, four knob controllers, and four switch controllers (all of which are reassignable).
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Given the cost, don’t expect boutique mic pre fidelity — but don’t expect consumer soundcard level, either. Perhaps more importantly, you can process the sound to get a variety of tonalities and character you couldn’t get from a straight preamp anyway. I’ve used the KB37 for income-producing projects, and it’s done an admirable job. The KB37 performs better than expected, and gives serious value. But there’s more to this than meets the eye. . . .


And how many times have you seen on forums “I dunno, I think I was more productive back when I just had a four-track and some processors”? Interestingly, the KB37 brought those days back to me; here’s why.

An integral part of the package is the GearBox software, which contains a bunch o’ amp models and guitar, bass, and vocal processors, all derived from Line 6’s Vetta line. These are not plug-ins, but instead, processors where you get your sound on the way in to your DAW. They also use Line 6’s ToneDirect monitoring process. This implements processing at the driver level, essentially bypassing all the overlays of Mac/Windows operating systems, so you can sing or play guitar with processing and hear no annoying delay.

Okay, that’s cool, but as you’re recording the processed signal — not a dry one processed by plug-ins — once you commit to a sound, that’s what gets recorded. The only way to change it after the fact is with EQ, reverb, and other standard mixdown-oriented processors.

That sucks, right? Hold on. For $199.99, the Line 6 website has an option where you can activate RTAS, AU, or VST (Windows) plug-in functionality for the GearBox software. But don’t buy it. At least, not yet.

Like so many other modern musicians, I can fall victim to “option overload.” I try to keep it under control, but sometimes it’s hard to commit to a sound when you know you can change it at any time. After working with the KB37 and GearBox, though, I re-discovered that commitment is good, because it lets you move on to the next part and keep the flow, just like you had to do with tape — and an inspired song beats a song where each part went under the microscope. Besides, I’m a decent player. If I really blow it in terms of the committed sound, I just re-cut.

The only bump in the road is I wasn’t thrilled with the patches that come with KB37, because they weren’t designed for my voice and my guitar. So I called up some that came close (once the Tone Select menu has focus, you can use the computer up/down arrow keys or KB37 buttons to scroll through them), tweaked them until I was happy, and saved them. So now, whenever I’m doing (for example) a video project, I plug in my mic, call up the “Craig’s Narration” vocal preset, and I’m laying down narration within minutes, if not seconds. Simple. Same with guitar: I have a library of about 12 fave patches, and when I need guitar, bingo — it’s there. Bass? Ditto (but I use the keyboard for MIDI synth bass parts too, as well as lots of other synth parts).

Yes, I activated the plug-ins because I use them for other purposes. But 98% of the time I just call up a patch I’ve created, tweak if necessary, and play.


You can read the KB37 specs all day — but that won’t tell you about the workflow, and how much the KB37’s philosophy speeds up a project, while preserving inspiration. Sure, I’d rather have world-class mic pres, a five-octave controller with aftertouch, and better controllers (the feel of the knobs isn’t great). Then again, I’d like a vacation home in Hawaii, too.

The bottom line is that I can truly say the KB37 has changed the way I do recording. I can’t quite believe this one piece of gear has made my sessions so much faster and more inspired . . . but it has.