MOTU 8pre

The MOTU 8pre USB is a handy multipurpose solution for your studio. For starters, it’s a powerful 24-bit/96kHz USB audio interface, boasting a full complement of eight microphone preamplifiers. Better yet, the MOTU 8pre USB has two banks of ADAT optical ports, so you can easily connect it into your existing interface system to beef it up with eight more preamplifiers. And, beyond all that, it has MOTU’s CueMix DSP functionality, so you can flexibly route audio to create separate monitor mixes and headphone mixes on the MOTU 8pre USB — with no latency.

Audio Quality

Turn your computer into a powerful digital audio workstation with eight mic inputs. Or add eight high-quality mic/instrument inputs to your current system.

The 8pre audio interface delivers everything you need to turn your computer into a powerful 24-bit, 96kHz digital audio workstation. The 8pre provides eight microphone/instrument preamps with pristine 96kHz analog recording and playback, combined with 8 channels of ADAT optical digital I/O. Expand your system by connecting additional 8pres or other MOTU audio interfaces.

The 8pre as your primary audio interface

Use the included CueMix™ software to mix all 16 inputs from your computer. Eight channels of ADAT optical I/O make the 8pre an ideal companion for a digital mixer. Two ADAT lightpipe connections work together to support a full 8 channels of optical digital I/O at any sample rate up to 96kHz.

Connect all of your studio gear, including microphones, guitars, synths, keyboards, drum machines and even effects processors. Then monitor all of these live inputs via the 8pre’s main outs or headphone jack — with virtually no monitoring latency and no processor drain on your computer. You can even create separate monitor mixes for the main outs and headphones. Control everything, including talk-back and listen-back, from the included CueMix Console™ software, just like a large studio console.

The 8pre includes a 16-channel MIDI interface. Simply connect the 8pre to your computer with any USB cable, and both MIDI and audio are ready to go. Connect any MIDI device, such as a controller keyboard, synth module, automated control surface or drum machine. Timing is sample-accurate with supporting software.

The 8pre provides cross-platform compatibility with Mac OS X (10.6 or higher), Windows (8/7/Vista) and all of your favorite audio software and host-based effects via WDM/ASIO/Core Audio drivers. Or you can use the included AudioDesk workstation software for Mac OS, with 24-bit recording/editing and 32-bit mixing/processing/mastering.

The 8pre as a microphone preamp expansion interface

The 8pre is really two products in one. When it is not connected to a computer via USB, the 8pre functions as an eight-channel analog to digital (optical) converter. Connect the 8pre to your MOTU 828, 896, Traveler or even another 8pre via the optical “lightpipe” connection to add eight high-quality microphone pre-amps to your system. Since the connection is digital, 100% pristine sound is maintained, down to the very last sample.

The 8pre is the perfect way to instantly add eight more mic inputs to any audio interface or digital mixer with optical I/O. If you have a MOTU interface with on-board CueMix DSP mixing, such as the 828 (mkII or mk3), 896 (HD or mk3) or Traveler (original or mk3), the 8pre inputs appear directly in the host interface’s CueMix mixer to becomes a transparent extension of your system, operating together with your primary interface as a single, integrated unit — even when the host interface is not connected to a computer and is instead operating as a stand-alone mixer.

If you have an 828mk3, 896mk3, 2408mk3, digital mixer or other audio device that supports 96kHz optical and also has two optical inputs, the 8pre connects to it via both optical ports to provide a full eight channels of analog to optical conversion at the 88.2 or 96kHz sample rates.

Inputs and Outputs

All inputs and outputs are independent and available at all times.

For example, using a mic-preamp input does not ‘steal’ an input from the ADAT optical input bank. As another example, the headphones and main outputs are available as separate mix destinations. In addition, CueMix DSP gives you all the flexibility you need. For example, you can configure CueMix DSP to mirror an existing mix bus to the headphones.

	Input	Output
mic preamps 24-bit 96-kHz on XLR/TRS combo	8	–
main outputs 24-bit 96kHz on bal/unbal TRS	–	stereo
headphone output	–	stereo
ADAT optical 24-bit 96-kHz (digital)	8	8
Total	16	12

MIDI

The 8pre includes a 16-channel MIDI interface that provides sample-accurate timing with supporting software.

Connect a MIDI keyboard, sound module or control surface, and you are ready to go. The 8pre’s USB connection to the computer carries both MIDI and audio so you don’t need to connect an additional USB cable for MIDI.

CueMix DSP™

The 8pre provides DSP-driven digital mixing and monitoring for all 16 inputs.

You can connect mics, guitars, synths and effects processors, and monitor everything from the 8pre’s main outs or headphone jack with no separate mixer needed and no latency.

The 8pre supports up to four separate stereo monitor mixes assigned to any digital or analog output pairs. For example, you could set up separate monitor mixes for the main outs and headphone outs, while two additional stereo buses could be used for send/return loops to a digital mixer. Each mix can support all 16 inputs (8 XLR/TRS analog and 8 ADAT optical digital).

Bounce Back

The “CueMix Bounce Back” feature lets you route one of the four CueMix DSP mixes back to the computer. This allows you to record, for example, your entire mix – including monitored inputs – back into the computer.

Tuner & analysis tools

CueMix DSP provides powerful audio analysis visual diagnostic tools for stereo audio signals, from an accurate guitar/instrument tuner to phase and polarity measurement tools, to a full-fledged oscilloscope. Find out how you can improve your sound with these advanced, yet easy-to-use tools.

Instrument tuner

Just open the Tuner window, play a note, and use the large graphic display to get in tune with an accuracy of one 10th of a cent (one 1,000th of a semi-tone). Being in tune has never been easier.

The Tuner displays the detected note by frequency (in Hertz), note name and octave, with an adjustable reference frequency for A4 between 400 and 480 Hz.

The large meter gives you a clear indication of how high or low you are from the detected pitch.

Large red arrows direct you up or down as needed to zero in on the correct pitch.

You can even tune phase-coherent stereo signals.

The CueMix DSP Tuner is as advanced and accurate as any dedicated hardware tuner out there.

FFT display and Spectrogram “waterfall”

CueMix DSP also provides real-time FFT and spectrogram “waterfall” display that provides rich, detailed visual information about the frequency content of any signal or mix. You can expand the spectrogram to fill the entire resizable CueMix DSP on-screen window.

X-Y Plot

The X-Y Plot window graphs a stereo signal on a standard grid with left-channel amplitude on the x-axis and right-channel amplitude on the y-axis. Stereo material that is said to be “in polarity” (i.e., phase aligned) appears along the x = y axis:

Stereo material that has phase problems will appear along the x = -y axis meaning the signal will appear predominantly in the upper left and lower right of the display. A signal with an extremely wide stereo field will appear much more randomly (not along either axis).

Phase Analysis

The Phase Analysis window graphs frequency versus phase difference versus amplitude of a stereo signal on either rectangular or polar coordinates. In the rectangular view, the vertical axis represents frequency, and the horizontal axis represents the phase of the left channel minus the phase of the right channel. Stereo audio that is predominantly in polarity will appear centered along the center vertical axis:

Frequencies that would be canceled by summing to mono are those that touch the -1.0 or +1.0 lines on the left and right.

In the polar view, the radius represents frequency and the angle (theta) from the +y vertical axis represents the phase difference of left channel minus the right channel. Stereo audio that is generally in phase will appear along the +y axis (above the center point). The more the audio signal “tips” to the left or right, the more out of polarity it is. If it is completely out of phase, it will point downwards from the center point and hover around the -y axis (the part of the y axis below the center point):

Applications

Phase analysis can be used for a broad range of applications in the studio and on the stage. Here are just a few ideas:

• Recording with multiple mics — the Phase Analysis window lets you compare multiple mic sources with each other to check for potential phase cancellation caused by varying distances in mic placement from the recorded source.
• Checking the overall polarity of a stereo mix — quickly check for phase issues in your stereo mix.
• Summing to mono — if your stereo material needs to be summed to mono, Phase Analysis lets you see what frequencies will be canceled out when summed.
• Tuning and checking PAs or sound reinforcement — place mics in strategic locations in your venue to check for critical phase issues in the listening environment.

Audio as visual art

The X-Y Plot and Phase Analysis displays make for some seriously freaky visual results, depending on the audio signal you run through them. If you do any visual effects work on the side, take note:

SMPTE

The 8pre provides on-board SMPTE time code synchronization features.

These features allow you to slave your 8pre system to SMPTE time code without a synchronizer via any analog input. The 8pre also generates time code, which can be sent to any analog output.

The 8pre provides a DSP-driven phase-lock engine with sophisticated filtering that provides fast lockup times and sub-frame accuracy.

The included MOTU SMPTE Console™ software provides a complete set of tools to generate SMPTE for striping, regenerating or slaving other devices to the computer. These synchronization features are cross-platform and compatible with all audio sequencer software that supports the ASIO2 sample-accurate sync protocol.

The 8pre as an optical converter

The 8pre is two products in one: a USB audio interface and an 8-channel analog-to-digital converter.

When the 8pre is not connected to a computer with a USB cable, the front panel “Mode” LED changes from “Interface” to “Converter”. In this mode, the 8pre acts as an 8-channel analog-to-digital converter that can add 8 mic inputs to another ADAT optical-equipped audio interface, digital mixer or other device.

For example, if you already own an 828, 896 or Traveler interface, you can connect the 8pre to the optical bank on your MOTU interface to seamlessly integrate the 8pre’s additional eight mic inputs into your MOTU interface CueMix mixer or host software mixer.

When operating in this mode, the 8pre simply routes each mic input signal to the corresponding optical output channel (mic input 1 goes to optical output 1, etc.) When connected to a MOTU host interface, such as the 828mkII shown above, these eight optical input signals are then routed directly into the host interface’s optical bank, so they appear side by side with all other inputs in the host interface’s CueMix Console, as demonstrated below, which shows the 828mkII CueMix Console with the eight optical inputs (the eight faders furthest to the right) renamed according to the mics, instruments and other sources connected to the 8pre mic inputs:

This approach has benefits over simply connecting the 8pre as a second USB audio interface. For example, it conserves USB bus bandwidth (for other devices, such as hard drives). It also streamlines your workflow by avoiding the extra setup procedures, software settings and performance issues often encountered when operating multiple USB interfaces connected to your computer. By connecting the 8pre optically to another interface, it becomes, in essence, a seamless extension of the other interface.

The 8pre has the ability to support 8 channels of optical output at 88.2 or 96 kHz (the 2x sample rates). This means it can be connected to another device that also supports 2x optical sample rates (via two sets of optical connectors) to add all eight mic inputs at 88.2 or 96 kHz. A perfect example is the 2408mk3, which provides three optical banks that can operate at 96 kHz. By connecting both optical banks from the 8pre to two optical banks on the 2408mk3, you add eight 96 kHz mic inputs. And they can be mixed as a seamless extension of the 2408mk3.

Feature Summary

• Hi-speed USB 2.0 audio interface for Mac and Windows — provides 16 inputs with 8 mic preamps and 12 outputs including separate phone and main outs for all the basic I/O you need for a powerful desktop studio.
• Eight XLR/TRS “combo jack” mic inputs — connect up to eight mics, or mix and match mics with guitars, synths, drum machines and other analog input signals.
• Flexible analog inputs — each provides a crystal-clear preamp (for both the XLR and TRS input), 24-bit 96 kHz converters, individually switchable 48-volt phantom power, 20 dB pad and front-panel trim controls. Mix and match condenser and dynamic microphones as your needs require.
• Eight channels of ADAT optical I/O — provides two sets of optical connectors to provide eight channels of optical digital I/O even at high samples rates (88.2 or 96 kHz).
• Operates as an optical expander — connect the 8pre to any ADAT optical compatible device (another audio interface, a digital mixer, etc.) to add 8 additional mic inputs seamlessly integrated into the mixing environment of the host device.
• Discrete ins/outs — there’s no channel sharing in the 8pre; the mic inputs, ADAT optical I/O, headphone out and main outs are all handled as separate channels.
• CueMix DSP™ near-zero monitoring system.
• Multiple CueMix DSP mixes — create up to eight different monitor mixes for the main outs and headphones. Add send/return loops for outboard gear with no latency.
• Front-panel metering — five-segment meters for all analog inputs, plus status lights for clock and interface/expander mode.
• Sample-accurate MIDI — connect a MIDI controller and/or sound module with no separate interface needed. MIDI I/O is sample-accurate with supporting software.
• Expandable — add additional MOTU 8pre, UltraLite, 828, 828, 896, or Traveler interfaces for additional I/O. Or connect the 8pre optically to any audio interface or mixer that supports ADAT optical I/O.
• Separate TRS main outs and front-panel headphone jack, each with independent volume control.
• SMPTE time code sync via any analog input.
• SMPTE time code generation to any analog output.
• Includes native 32- and 64-bit drivers for Mac OS X (10.6 or higher) and Windows (10/8/7/Vista), including ASIO, WDM, Wave, Core Audio, and Core MIDI. Supports all popular Mac and Windows audio software.
• 100% compatible with all host-based effects processing in today’s popular audio programs.
• Includes AudioDesk full-featured sample-accurate workstation software for Mac and Windows with recording, editing, mixing, real-time 32-bit effects processing & sample-accurate sync.
• Plug-and-play operation with your Mac or PC via USB.
• Chassis dimensions, excluding rack ears and front and back panel knobs and connectors: 19 × 7 × 1.75 inches (48.26 × 17.78 × 4.45 cm). Knobs and connectors extend up to 0.5 inch (1.27 cm) from front and back panels, adding 1 inch (2.54 cm) to depth. With rack ears attached, fits standard 19 inch (48.26 cm) rack at 1U high.