Vocalists and guitarists get to use wireless microphones and belt-pack transmitters to free themselves from the constraints of audio cables onstage. Wireless technology has trickled down to basically everyone by now; even grandmas gossip without care on cordless phones. So why is it that keyboardists and electronic musicians still find themselves tethered to their gear by MIDI cables? Wireless MIDI setups (such as the Gambatte MIDIStar Pro) have been around since the mid-'80s, but at several thousand dollars for a system (one transmitter and one receiver), they cost too much for budget-minded musicians. Fortunately, the price for a dependable wireless MIDI setup finally has fallen dramatically. There are now several models to choose from, starting at around $250 for a complete setup.
WIRED IS FIRED
Wireless MIDI systems come in two flavors; either the transmitter is built into a controller (such as a MIDI keyboard), or the transmitter is a wearable belt-pack unit that accepts the MIDI output from your controller. The transmitter — whether built-in or in belt-pack form — generally operates on batteries (usually AA or 9V). The receiver is a separate box — either rackmountable or a tabletop unit — and generally draws its power from a wall-wart AC adapter.
The obvious advantage of having a transmitter built into a keyboard controller is that you will never have to attach (sometimes with duct tape) an awkward and heavy belt pack onto your outfit. The downside is that you can't use the transmitter with any other MIDI controllers. The only affordable keyboard controller/transmitter to date is the new M-Audio MidAir 25 ($250). It looks and feels like the company's classic Oxygen8 controller but is outfitted with wireless technology from Frontier Design (the makers of the TranzPort wireless remote DAW controller).
Clearly, the upside to a belt-pack transmitter is that you can use it with your own keyboard controller. For example, if you prefer more of a rock-guitar-god stage presence, strap on a Roland AX-7 controller and connect it to your belt-pack transmitter. There are several models that employ the belt-pack design: the Kenton Electronics MIDIStream ($650), the Classic Organ Works MIDIjet Pro ($495) and the CME WIDI-X8 ($250).
In a perfect world, nothing would ever interfere with your wireless reception — no cordless phones, local RF, microwaves or line-of-sight obstructions. In reality, there are a lot of sources for potential interference that can royally screw up your signal. Though it's easier to control the environment in your recording studio — just ask roommates to get off the cordless phone and not use the microwave when you're recording — it's another ball-game altogether when you step onstage, from reception conflicts with other band members' wireless systems to a neighborhood broadcasting tower. Even the 2.4 GHz radio frequency that most of the aforementioned systems employ (except the MIDIStream, which operates at 914.5 MHz) is not immune to a lost or scrambled signal.
A diversity receiver is often used to improve performance. Most diversity receivers distinguish themselves with their two antennae (such as the MIDIstream). The receiver continuously scans the incoming signal on both antennae and then smoothly and automatically switches to whichever signal is the strongest. Even systems without the obvious antennae (such as the MidAir) use automatic frequency-switching techniques to improve signal reception. Many manufacturers also go a step further by fingerprinting the transmitters and receivers, so that they will only work as a pair. The process, which Classic Organ Works calls “binding,” is applied to every MIDIjet Pro system before leaving the factory. Binding greatly reduces the risk that multiple wireless systems on the same stage might interfere with each other.
Another way to reduce the risk of interference is to keep the transmitter in a direct line of sight with the receiver. Of course, during a performance, this is much easier said than done. When you're setting up for the gig, take note of the area in which you'll be playing, imagine where your bandmates will be and put your receiver in a spot that will not be blocked during the show. That may require looking above or beyond the stage. Remember, the receiver is wired, so you can stick it just about anywhere that your cables will reach. A transmitter's operating distance varies from model to model, from 500 feet for the MIDIjet to 30 feet for the MidAir. You do not want to experiment with the maximum signal distance during a live performance, and most of the manufacturer's reported distances will be much less in a crowded club.
SORRY FOR THE DELAY
Keep in mind that all virtual instruments have inherent latency — the amount of time it takes you to hear a sound after pressing a key on your MIDI controller. As a rule, the faster your computer and the better your audio interface (and its drivers), the lower the latency. Depending on how sensitive you are to latency when you're playing live, going wireless may cause latency times to become increasingly apparent. To minimize the problem, go for the fastest computer possible (such as the Apple MacBook Pro) and a high-quality audio interface (such as the MOTU Traveler). Also, make sure your virtual instruments hosts' audio-buffer setting is as low as your computer can handle (512 samples or less). That will reduce latency but require more processing power to run your virtual instruments, so you'll probably need to tweak the buffer setting to fit your playing style and situation.
The good news is that wireless MIDI systems are now affordable. Keyboard players and electronic-music jocks can romp in the spotlight free of ensnaring MIDI cables. So break free of those shackles and experience the freedom of wireless.