PreSonus Blue Tube

Page 1, 2, 3

App Happy

Click image to view table.

The Blue Tube has dozens of uses. It fit into my bag so easily that I became accustomed to bringing it along to sessions and concerts, even when I didn’t have a clear idea as to how I might employ it. But once I arrived at the studio or venue, I always found a use for it—and sometimes I could not have done as good a job without it.

The Blue Tube is very handy as a DI box for stereo instruments such as keyboards, either live or in the studio. Not only does it provide ample gain and distortion, but also, as suggested earlier, its simultaneously available outputs let you use it as a splitter. For example, you could send signal directly to a console or tape machine through the XLR outputs and to an amplifier or personal monitor through the 1/4-inch outs.

The Blue Tube also works well with electric guitar, whether as a preamp before a guitar amp or simply as a DI. I tested the unit as a DI using a Strat plugged into one of the instrument inputs and found that it yielded clean gain, effective and likable distortion, and any combination of the two. The Gain and Drive knobs interact in an additive fashion, with the solid-state amplification controlled by the Gain knob and the tube acting on the signal only as the Drive knob is turned up—a design that allows for a range of variations between clean and dirty tones. (Just remember, as with any tube unit, you should let the tube warm up before engaging the Drive knob.)

The Blue Tube is also helpful when you need extra juice to send a signal down a long cable. When recording a guitar or keyboard cabinet at home, for example, it’s often necessary to position the cab far from the record deck—in a bedroom closet, for instance—to achieve adequate sound isolation. The Blue Tube provides plenty of gain for getting the signal to its destination.

Another feature I found very helpful was the Blue Tube’s polarity-reverse switches. I typically use two mics to record guitar amp cabinets (usually a Shure SM57 and a Sennheiser 421). Because the sound arrives at the two capsules at different times, that technique can lead to phase distortion. A quick and easy way to hear if the two capsules are out of phase is to reverse the polarity on one of the two mics. However, not many mixers—especially among those commonly found in personal studios—provide polarity reversal. The Blue Tube’s independent polarity-reverse switches really come in handy, making it easy to quickly hear phase problems.

The Blue Tube is a great tool for location recordists who specialize in stereo recording, whether to DAT, hard disk, or whatever else. Many DAT recorders provide mic preamps, but only a few offer phantom power. Similarly, if you record direct to hard disk using, say, a PowerBook, you’ll need preamps and phantom power.

For live recordings of bands, I used the Blue Tube to power various mics, including pairs of Shure SM57s, AKG C 414s, Countryman Iso-Omnis, and Radio Shack PZMs. The unit worked well with all of these. I even used the Blue Tube solely as a phantom-power box during a live recording using a transformer-isolated snake splitter (a device that cannot pass phantom power because of the transformers).

Reprinted with permission from

[an error occurred while processing this directive]