ProFire Lightbridge Review by Tej Gill
M-Audio ProFireLightbridge
Although it’s not a brand new product, M-Audio’s ProFire Lightbridgeis one of those things that make you wonder how you got on without it. Withtwo knobs, a headphone jack, a power switch and some LEDs on the front panel,the Lightbridge probably won’t be the most exciting looking piece of gearin your studio. But looks can be deceiving, under the hood of the Lightbridgelurks a 34-in/36-out ADAT Lightpipe Interface making it the perfect connectionbetween your computer DAW and your digital mixer. It connects to your computervia a single Firewire cable.
Let’s take a look at how M-Audio squeezes so many ins & outs intoa relatively small box. Four ADAT optical inputs provide 32-channels and a S/PDIFinput gives you another two channels, bringing the sum total of inputs to thirty-four.An additional four ADAT optical connectors provide 32-channels of output, aS/PDIF provides another two, and a pair of ¼” analog phone jacksbring the sum total of outputs to thirty-six. The analog-outputs are controlledby the Output Level knob on the front panel, making them perfect to feed a pairof powered monitors. The Lightbridge also has one MIDI in/out.
The ProFire Lightbridge supports sample rates up 96kHz. at up to 24-bit resolution.One thing to point out here is that if you plan on using 88.2 or 96kHz. samplerates, each ADAT port will drop down to handling four channels of audio insteadof eight. This is due to the S/MUX mode of the ADAT interface and is normal.If you plan on running your audio at a high-resolution sample rate, the input/outputsection of the Lightbridge will be halved due to this.
MIDI in/out, S/PDIF in/out and Word Clock sync are all on a breakout cablewhich connect to the main unit via an RS-232 type connecter. With all this digitalin and out, Word Clock sync becomes an important issue, and M-Audio knows this.The ProFire Lightbridge can act as a Word Clock Master or Slave, depending onyour particular setup. The manual goes into a number of different scenarios,with diagrams showing where to connect things to make it work.
The front-panel of the Lightbridge is pretty simple and straight-forward. Thereis a panel of LEDs that communicate what’s going on with the unit, andwhat types of signals it is receiving or transmitting. Included in this panelare LED’s to indicate status of: Sample Rate, Sample Rate Multiplier (usedin S/MUX mode), Sync Mode, MIDI signals, and Optical I/O Activity. These LEDsshould make trouble-shooting easier in the event of a problem.
The ProFire Lightbridge can work with either Windows XP or Mac OSX. It’salways good practice to check for driver updates before setting up the unitto make sure you have the latest and greatest. It also works with Pro ToolsM-Powered, however, is limited 18 inputs and outputs under it.
If you work with digital mixers and need to route signal in and out of thecomputer, the ProFire Lightbridge is a convenient way to do that. Its very flexiblearchitecture means you can route just about any signal to anywhere else in yoursetup via your host DAW, making it a “digital patch-bay” of sorts.And since it can be bus-powered, the Lightbrdige would work well in portableapplications as well. The ProFire Lightbridge is the perfect product if youhave a lot of digital signals to route in and out of your computer.
