The Alesis iO2 EXPRESS is a capable recording interface for musicians who want the convenience of making music on their computers. It’s compatible with both Mac and PC operating systems. The Alesis iO2 uses your computer’s own USB port, which eliminates the need for an outside power supply. The interface provides a compact, two-channel solution that allows you to record up to 24-bit, 48 kHz audio using any software. This sleek, compact accessory also offers inputs for microphones, line-level sources, and instruments. The equipment comes bundled with sophisticated Steinberg Cubase LE digital audio workstation (DAW) software. This Cubase software contains an assortment of sophisticated editing, scoring, and mixing tools.The Alesis iO2 USB recording interface measures 5 by 6.2 by 2 inches, and it weighs 12.8 ounces. It’s a portable piece of equipment that you can easily slip into a backpack or a laptop bag. Its electronic components are enclosed in a durable aluminum casing. At the top left of the front of the aluminum case, you’ll find a USB port, which connects to your laptop. Just beneath the USB port and slightly to the right is a microphone input port. You can connect your microphone to one of these Alesis iO2 USB accessories using any XLR cable. Just below the mic input is a port for connecting to an instrument or low-line device as well an Insert port. The Insert port allows you to link your Alesis EXPRESS to a compressor, an equalizer, or some other type of audio signal processor. Next to the line of LED lights that bisects your Alesis device, you’ll see two switches. The Mic/Line and Guitar switch accesses a high-impedance output channel for connecting a guitar or bass when it’s switched to Guitar. When it’s switched to Mic/Line, the channel will accept audio signals from microphones or other line-level equipment. The Phantom Power switch facilitates the transmission of DC electrical power, which is necessary in order to run a condenser microphone. You can use up to 48 volts of power when you run your compressor microphone. To the left of this switch is the Gain knob that adjusts the volume of the pre-fader and pre-equalizer audio levels. Beneath the Phantom Power port is a switch that allows you to adjust your headphones for stereo or mono. The microphone input jack is at the bottom of the left side of the Alesis iO2 USB recording interface along with the microphone’s volume controls.On the right side of these iO2 accessories, you’ll discover another input port for connecting a microphone using an XLR cable. Another pair of Guitar and Insert jacks are below that input port as well as another Guitar switch and another Gain knob. At the bottom of the right side of the Alesis interface case, you’ll see the Monitor Mix knob. This permits you to blend audio signals from your various inputs with your computer’s audio outputs.Down the middle of the Alesis iO2 interface case are a line of LED lights. The highest is a meter that monitors the audio level of your main output. Underneath it is a light that illuminates when the USB on your EXPRESS interface is making a good connection with your computer. Beneath that is a Midi Out light that illuminates when you’re successfully importing MIDI data from an external controller. The very bottom LED light illuminates whenever you’re using phantom power.