61. Introduction1.1 OverviewThe US-428 is a USB controllerprimarily designed for Digital AudioWorkstation (DAW) softwareapplications. Its design incorporates afour-input, two-output 24-bit audiointerface, a dual MIDI interface, and acontrol surface for your most-usedmouse functions.Our goal was to create a device to makeyour DAW software as easy to use as aPortastudio. The transport and othercontrols are designed and laid out tolook and function just like a Portastudio– if you’ve ever used a tape recorder,you know how to use the US-428.Because the US-428 is USB based, it’sthe ideal companion to any desktop- orlaptop-based digital recording setup.And since it’s as compact as a laptop, itcan be combined with one to create acomplete portable digital audioworkstation solution.1.2 FeaturesThe input section comprises a 24-bitaudio interface, capable of streaming upto four simultaneous tracks of audio intoyour computer. Inputs include twobalanced XLR mic inputs, two balanced1/4” TRS inputs, two 1/4” unbalancedline inputs (switchable to high-impedance, for direct input of a guitar,bass or other hi-Z source), and anS/PDIF digital input. Outputs include apair of unbalanced line outputs on RCAconnectors, S/PDIF output, andseparate headphone output.The US-428 also features twoindependent MIDI I/O ports, allowingyou to send and receive data and MIDITime Code from your MIDI-basedkeyboards and other devices. You can,for example, use one port for MIDImodules and devices, and the other tosynchronize your MIDI Time Codecapable Portastudio, DTRS or othermultitrack tape machine with your digitalaudio software.The US-428’s control surface includes avariety of controls which make workingwith audio software faster and easier.The channel section of the controlsurface consists of eight channel faders(plus one master fader), eight mutebuttons, a switch to toggle Solo andMute functions, and individual record-ready and select switches. The mastersection features four Aux Sends, adedicated EQ module (with continuouscontrollers for level, frequency and Q, aswell as four band-selection buttons), adata wheel and four application-definedsoft keys. Dedicated transport andlocate controls offer one-button accessto these often-used functions.1.3 Special Note RegardingProgramming of the US-428The many faders, switches and othercontrols on the US-428 make it anextremely versatile device. The basicoperational premise behind the US-428