MOTU 828mk3 FireWire Audio Interface

I/O

The 828mk3 provides 28 inputs and 30 outputs in a single rack-space form factor. All I/O is routed to an on-board 16-bus digital mixer driven by hardware-based DSP with 32-bit floating point precision. The mixer allows users to apply no-latency effects processing to inputs, outputs or busses directly in the 828mk3 hardware, independent of the computer. Effects can even be applied when the 828mk3 is operating stand-alone (without a computer) as a complete rack-mounted mixer. Input signals to the computer can be recorded wet, dry, or dry with a wet monitor mix (for musicians during recording, for example).

Eight balanced (TRS) 24-bit analog inputs and outputs, as well as two XLR main outs and the two preamp inputs, can operate at sample rates up to 192 kHz (a total of ten analog inputs and outputs). Two optical banks provide 16 channels of ADAT optical at 48 kHz, 8 channels of S/ MUX optical I/O at 96 kHz or two banks of stereo TOSLink at rates up to 96 kHz. The banks operate independently, allowing users to mix and match any optical formats. RCA S/PDIF connectors also supply independent stereo digital I/O. Each mic input has a corresponding rear panel send that allows users to insert outboard gear before the signal goes digital. Any input can be used as a return.

Effects

Effects include reverb, parametric EQ and compression/limiting. The 828mk3 's Classic Reverb provides five different room types, three frequency shelves with adjustable crossover points, shelf filtering and reverb lengths up to 60-seconds. Two forms of compression are supplied: a standard compressor with conventional threshold/ratio/ attack/release/gain controls and the Leveler, an accurate model of the legendary LA-2A optical compressor, which provides vintage, musical automatic gain control. Finally, the EQ section provides 7- band parametric EQ modeled after British analog console EQ 's, featuring 4 filter styles (gain/Q profiles) to effectively cover a wide range of audio material. LP and HP filters are also supplied with slopes that range from 6 to 36dB.

The 828mk3 's flexible effects architecture allows users to apply EQ and compression on every input and output (a total of 58 channels), with enough DSP resources for at least one band of parametric EQ and compression on every channel at 48 kHz. However, DSP resources are allocated dynamically and a DSP meter allows users to keep tabs on the 828mk3 's processing resources. Each input, output and mix bus provides a send to the Classic Reverb processor, which then feeds reverb returns to mix buses and outputs, with a selectable split point between them to prevent send/return feedback loops.

Overload protection

Individual 48V phantom power and 20 dB pad switches are supplied for each of two front-panel mic/guitar combo jacks, which are both equipped with preamps. Both inputs also now include a switch that toggles between the low-impedance XLR mic input and the true (high- impedance) quarter-inch guitar input jack. Both mic/guitar inputs are equipped with V-Limit, a hardware limiter that helps prevent digital clipping from overloaded input signals. With V-Limit enabled, signals can go above zero dB (where limiting kicks in) to as high as +12 dB above zero with no distortion due to digital clipping. Additional protection can be applied to the mic/guitar inputs by enabling the 828mk3 's Soft Clip feature, which engages just before clipping occurs and helps reduce perceptible distortion.

Digitally controlled analog input trim

All of the 828mk3 's analog inputs are equipped with digitally controlled analog trim controls that allow adjustments in precise 1 dB increments. The mic/guitar input trims can be adjusted using front- panel digital rotary encoders that provide feedback in the front panel LCD. All analog inputs, including eight TRS analog inputs, can be trimmed using the CueMix FX control software for Mac and Windows. This allows users to fine-tune their trim settings for synths, effects modules and a wide variety of analog inputs for optimum levels. Different trim configurations can then be saved as files on disk for instant recall.

CueMix FX software

All of the settings in the 828mk3 are accessible from the programmable front-panel backlit LCD. Users can also launch the CueMix FX control software for Mac OS X, Windows XP and Windows Vista. CueMix FX is a completely new software front-end with attractive graphic mixing, graphic editing of parametric EQ and a convenient tabbed interface for quick access to all features in one window. Three separate tabs show inputs, mix busses (eight stereo busses) and outputs. Users click a "Focus" button on any channel or bus to edit its settings in another area on the right-hand side, which provides separate tabs for graphic editing of parametric EQ, compression and other effects. Each channel displays a graphic thumbnail of EQ curves, compressor settings and other channel specific parameters. There is also a section for talkback and listenback. CueMix FX can be operated side by side with any host audio software for Mac or Windows, and it can be controlled from the Mackie Control Universal Pro automated worksurface.

Synchronization

The 828mk3 is equipped with Direct Digital Synthesis (DDS), a DSP-driven phase lock engine and internal clock source that produces imperceptibly low jitter characteristics (below the noise floor), even when the 828mk3 is resolved to an external clock source via either word clock or SMPTE time code. The 828mk3 can directly resolve to (or generate) time code via a dedicated quarter-inch time code input and output, without the need for an extra synchronizer.

Expansion, Drivers and AudioDesk

As with other MOTU FireWire interfaces, the 828mk3 supplies two FireWire jacks so it can be daisy-chained with additional MOTU FireWire audio interfaces or other devices. The 828mk3 is also fully compatible with the 8pre, a single rack MOTU interface that adds 8 mic preamp inputs to the 828mk3. Because the 8pre connects to the 828mk3 via ADAT optical, its mic inputs are fully integrated into the 828mk3 's on-board CueMix FX digital mixer.

The 828mk3 provides CueMix FX and drivers for Mac (OS X) and Windows (XP and Vista) for cross-platform compatibility with virtually all audio software via WDM/ASIO/Core Audio drivers. The included AudioDesk workstation software for Mac provides 24-bit recording/editing and 32-bit mixing/processing/mastering.