8A ™ User Guide Title Page 1280 Massachusetts Avenue Cambridge, MA 02138 Business voice: (617) 576-2760 Business fax: (617) 576-3609 Web site: www.motu.com Tech support: www.motu.
SAFETY PRECAUTIONS AND ELECTRICAL REQUIREMENTS FOR THE 8A (“PRODUCT”) CAUTION! READ THIS SAFETY GUIDE BEFORE YOU BEGIN INSTALLATION OR OPERATION. FAILURE TO COMPLY WITH SAFETY INSTRUCTIONS COULD RESULT IN BODILY INJURY OR EQUIPMENT DAMAGE. HAZARDOUS VOLAGES: CONTACT MAY CAUSE ELECTRIC SHOCK OR BURN. TURN OFF UNIT BEFORE SERVICING. WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRICAL SHOCK, DO NOT EXPOSE THIS APPLIANCE TO RAIN OR OTHER MOISTURE.
Contents Part 1: Getting Started 7 Quick Start Guide 9 8A Front Panel 10 8A Rear Panel 11 MOTU Pro Audio Control Web App 23 About the 8A 27 Packing List and System Requirements 29 Software Installation 33 Hardware Installation Part 2: Using the 8A 49 Presets 53 The Front Panel LCD 55 Working with Host Audio Software 63 Mixer Effects 71 MOTU Audio Tools 87 Networking Part 3: Appendices 95 Troubleshooting 97 Audio Specifications 99 Mixer Schematics 103 Updating Firmware 105
About the Mark of the Unicorn License Agreement and Limited Warranty on Software TO PERSONS WHO PURCHASE OR USE THIS PRODUCT: carefully read all the terms and conditions of the “click-wrap” license agreement presented to you when you install the software. Using the software or this documentation indicates your acceptance of the terms and conditions of that license agreement. Mark of the Unicorn, Inc. (“MOTU”) owns both this program and its documentation.
Part 1 Getting Started
Quick CHAPTER Start Guide Thank you for purchasing an 8A! Follow these easy steps to get started quickly. 1 Download and run the MOTU Pro Audio Installer found here: http://www.motu.com/avb You should now see the MOTU Pro Audio Control web app in your browser, as shown on page 12. If not, visit Appendix A, “Troubleshooting” (page 95). ■ ■ For advanced network options, and device discovery from any modern browser, see chapter 10, “Networking” (page 87).
8A Front Panel 7 1 1. HEADPHONE OUTPUT with volume control. The LCD provides visual feedback with a volume meter. Doubletap the knob to mute/unmute. Hold in the knob to lock the volume meter on screen; hold it in again to unlock and dismiss. 2. Push ID to display network settings for the device, including its IP address. 2 3 3. Push SEL (select) to enter the LCD menu. Push the ARROW buttons to scroll through menu options. Push SELECT again to descend into the submenus, if applicable.
8A Rear Panel 1 5 2 3 4 6 1. These ADAT optical “lightpipe” jacks provide 8 channels of 24-bit ADAT optical digital I/O at 1x sample rates (44.1 or 48 kHz) and 4 channels at 2x sample rates (88.2 or 96 kHz). They are disabled at higher sample rates. Alternately, they can operate as stereo TOSLink (optical S/PDIF) connectors. 2. Connect the 8A to the computer here with Thunderbolt or USB 3.0, using a standard Thunderbolt or USB cable (one or the other, but not both).
MOTU Pro Audio Control Web App CHAPTER OVERVIEW MOTU Pro Audio Control is a web app that gives you complete control over the 8A. If you have several MOTU AVB interfaces networked together, such as the 8A, 1248 and 8M, you can control them all. If you are working with a large network of many MOTU AVB interfaces, you can access any device on the network. MAKE HARDWARE AND NETWORK CONNECTIONS Connect your 8A to your computer or laptop with a USB or Thunderbolt cable.
DEVICE TAB 6 7 8 9 10 5 11 12 4 3 2 13 14 1 15 Windows only 16 17 18 19 1. If you have two or more MOTU AVB interfaces, the Devices list lets you choose the one you are currently controlling with the web app. 2. The Aux Mixing tab lets you view each Aux bus in the mixer, one at a time. 3. The Mixing tab gives you access to the mixing and DSP in the interface. 4.
DEVICE TAB (CONTINUED) 21 20 22 24 23 Scroll down to view these additional Device tab settings. 20. AVB is IEEE’s Audio Video Bridging Ethernet standard for highbandwidth, low-latency audio streaming over Ethernet. If your MOTU interface is connected to a 2nd MOTU interface through its network port, or to an AVB switch for access to an extended AVB network, you can stream audio channels to and from other devices on the network.
DEVICE TAB (CONTINUED) 25 26 32 31 27 28 30 29 Scroll down to view these additional Device tab settings. 25. In the Computer Setup section, you can specify how many audio channels you would like to be able to stream to and from your computer, up to 128 channels each way, simultaneously, over USB or Thunderbolt. Map them as desired in the Routing tab (page 15). 26.
ROUTING TAB 4 5 6 7 8 9 10 11 3 12 2 13 14 1 21 20 15 19 18 16 17 The Routing Tab lets you route inputs to outputs. Outputs are listed by row on the left; inputs are listed in columns across the top. Simply click in the grid to make a single connection. Click and drag to make multiple connections in one gesture. To route a single input to multiple outputs, make multiple connections vertically in the same column below the input.
MIXING TAB 3 4 5 6 7 8 9 10 11 12 13 14 15 16 2 17 1 18 19 32 31 20 30 29 21 22 28 23 24 25 27 The Mixing tab gives you full access to the 48-channel mixer in the 8A, which provides a main mix bus, monitor bus, three group busses, seven aux busses, and a dedicated reverb bus. Use the Device tab to configure how many inputs you wish to work with (up to 48). Use the Routing tab (page 15) to route channels to the mixer inputs.
AUX MIXING TAB 3 4 5 6 7 8 9 10 2 1 17 11 12 13 16 15 14 The Aux Mixing tab provides quick access to the 8A’s mix busses (aux busses, groups and reverb bus), viewed one at a time. Choose a bus in the Aux Mix Target section and then use the faders to directly mix the send levels from all mixer inputs, groups, and the reverb bus. 4. Click the aux bus or group you wish to view in the window. In this example, Aux bus 1-2 is being displayed. 5.
MIXER INPUT CHANNEL STRIPS 1 2 6 7 8 4 5 To access a mixer input channel strip, go to the Mixing tab (page 16), reveal the side bar (item #3 on page 16), and then show the input channel you want in the Mixer Inputs section (31). To show and hide sections of the channel strip, such as EQ or the compressor, use the Controls section of the side bar (item #3 in the Mixing tab on page 16). 30 29 3 2 9 3 1. Click the input channel name to change it. Delete the current name to restore the default name.
MAIN MIX AND MONITOR CHANNEL STRIPS 1 2 3 4 3 5 6 4 5 7 15 To access the Main Mix and Monitor bus channel strips, go to the Mixing tab (page 16) and scroll the display to the right, beyond the inputs and groups. To show and hide sections of the channel strip, such as EQ or the Leveler, use the Controls section of the side bar (item #3 in the Mixing tab on page 16). 8 9 1. By default, the Monitor bus serves as a solo bus.
AUX BUS CHANNEL STRIPS 1 11 2 3 Aux busses can be used to create sub-mixes. An aux bus can be assigned to any output in the Routing grid (page 15). 4 To access an Aux bus channel strip, go to the Mixing tab (page 16), reveal the side bar (item #3 on page 16), and then show the aux busses you want in the Mixer Outputs section (28). To show and hide the four-band EQ section of the channel strip, use the Controls section of the side bar (item #3 in the Mixing tab on page 16). 10 1. A stereo aux bus. 2.
GROUP AND REVERB CHANNEL STRIPS 1 2 10 3 Group busses can be used to create a mix subgroup, which is a set of inputs you wish to control together as a group. Groups differ from aux busses in that they have aux sends, a reverb send, as well as a main mix send. In addition, group busses are equipped with the Leveler. The Reverb bus is a special group bus that provides a reverb processor. If you disable the reverb, the reverb bus functions as a (fourth) regular group bus.
MOTU PRO AUDIO CONTROL WEB APP
CHAPTER 1 About the 8A The 8A is an 16 x 18 Thunderbolt/USB/AVB audio interface with console-style 48-channel mixing, DSP effects, wireless control, AVB audio networking and very high quality A/D/A conversion at sample rates up to 192 kHz for onthe-go mobile audio recording. Powerful DSP delivers large console style mixing with 48 channels, 12 stereo busses, and 32-bit floating point effects processing, including modeled analog EQ, vintage compression and classic reverb.
AVB/TSN system expansion and audio networking AVB stands for the IEEE 802.1 Audio Video Bridging Ethernet standard for high-bandwidth, low-latency audio streaming over Ethernet. You may also hear AVB referred to as AVB/TSN or simply TSN because the IEEE is in the process of renaming the standard to Time Sensitive Networking to accommodate the expanding scope of the specification to applications beyond audio and video.
DAC, also adjustable in 1 dB increments. You can save your trim configurations as a preset for instant recall. Rack mount or desktop operation The 8A is housed in a sturdy, metal-alloy half-rack enclosure. Rack mounting brackets are included for mounting side by side with any other MOTU half-rack unit. AudioDesk AudioDesk is a full-featured audio workstation software package for Mac and Windows that is available as a free download for you as an 8A owner. Visit motu.com/avb to obtain your copy.
ABOUT THE 8A
CHAPTER 2 Packing List and System Requirements PACKING LIST PLEASE REGISTER TODAY! the 8A ships with the items listed below. If any of these items are not present in the box when you first open it, please immediately contact your dealer or MOTU. Please register the 8A today. There are two ways to register.
PACKING LIST AND SYSTEM REQUIREMENTS
CHAPTER 3 Software Installation OVERVIEW USB audio class-compliant operation. . . . . . . . . . . . . . . . Software installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Audio drivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MOTU Discovery app . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MOTU Pro Audio WebUI Setup for Windows . . . . . . . . . AudioDesk workstation software . . . . . . . . . . . . . . . . . . . .
AUDIO DRIVERS The installer provides Thunderbolt and USB audio drivers for Mac (CoreAudio) and Windows (ASIO and Wave). MOTU Pro Audio ASIO Driver On Windows, to enable the 8A in your ASIO host software, choose the MOTU Pro Audio ASIO driver. Thunderbolt support for Mac and Windows You can connect your MOTU interface to a Thunderbolt-equipped PC and access up to 128 channels of simultaneous audio input and output using the MOTU Pro Audio ASIO driver.
Choose an interface to access its settings through the web app (“MOTU Pro Audio Control Web App” on page 11). MOTU PRO AUDIO WEBUI SETUP FOR WINDOWS Figure 3-2: Access the ‘Host Buffer Size’ and ‘Host Safety Offset’ settings in the web app Device tab for your MOTU interface. Be careful with very small buffer sizes, as they can cause performance issues from your host software or PC. ☛ At sea level, audio travels approximately one foot (30 cm) per millisecond.
SOFTWARE INSTALLATION
CHAPTER 4 Hardware Installation OVERVIEW Thunderbolt audio interface setup . . . . . . . . . . . . . . . . . . 33 USB or iOS audio interface setup . . . . . . . . . . . . . . . . . . . . 33 AVB Ethernet audio interface setup. . . . . . . . . . . . . . . . . . 34 Setup for two interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Setup for three to five interfaces. . . . . . . . . . . . . . . . . . . . . 35 Setup for a multi-switch network . . . . . . . . . . . . . . . . . . . .
AVB ETHERNET AUDIO INTERFACE SETUP SETUP FOR TWO INTERFACES OR Use this setup if you want to use the 8A as an AVB Ethernet audio interface for a recent-generation Mac (i.e. any Mac with a Thunderbolt port on it). OS X El Capitan (10.11) or later is required for AVB audio I/O. ■ Use a standard CAT-5e or CAT-6 cable. ■ Connect to the computer’s Ethernet port. See “Setup for AVB Ethernet audio interface operation” on page 40. Use this setup if you want to connect two MOTU interfaces to your computer.
SETUP FOR THREE TO FIVE INTERFACES Use this setup if you want to connect three to five MOTU interfaces to your computer using a MOTU AVB Switch™ (sold separately). ■ The connection to the computer can be USB or Thunderbolt (if you have a Thunderbolt-equipped MOTU AVB interface). Use Thunderbolt or USB 3.0, if possible, to support a large number of audio streams to and from the networked interfaces. A single Thunderbolt or USB 3.0 connection supports 128 channels in and out, simultaneously.
SETUP FOR A MULTI-SWITCH NETWORK ■ You can daisy-chain switches in serial fashion, but don’t create loops. For example, switches A, B, and C below are chained properly, but don’t connect C back to A. Alternately, you could connect both Switches B and C to Switch A. Use this setup if you want to connect more than five MOTU interfaces to an extended network that employs multiple AVB switches. AVB Ethernet is an industry standard, so you can use MOTU AVB Switches or 3rd-party AVB switches.
SETUP FOR MULTIPLE INTERFACES It is possible to connect multiple MOTU interfaces directly to your host computer through multiple USB (and Thunderbolt) ports. However, there are several disadvantages to using any of these direct connection schemes: ■ The audio interfaces will not be clocked to one another and may be susceptible to drift, unless you use external word clock connections (if available). You are better off using the AVB network connections shown on pages 34-36.
SETUP FOR WEB APP CONTROL The MOTU Pro Audio Control web app gives you access to all settings, routing, mixing, and effects processing in the 8A, and each interface on the AVB network, if applicable. For more info, see “MOTU Pro Audio Control Web App” on page 11. The web app is a web application served by the hardware. All you need to run it is a web browser running on a device that has a connection to your audio interface through Thunderbolt, USB or a shared network.
Ethernet cable A simple Ethernet cable connection can be used for web app control, even without a USB or Thunderbolt connection to your computer. For example, if you are using your MOTU device as a mixer or audio router, you could control the on-board routing, mixing and effects from the web app through a standard Ethernet connection. Wi-Fi When using standard Wi-Fi as shown, you can control the 8A from multiple Wi-Fi devices simultaneously.
SETUP FOR AVB ETHERNET AUDIO INTERFACE OPERATION Your MOTU hardware can serve as an Ethernet audio interface when connected to a recent generation AVB-equipped Mac. You can then use your MOTU interface as a standard multi-channel audio interface with any Core Audio compatible host software running on the Mac. 1 Launch the MOTU Discovery app.
☛ MOTU interfaces currently only support 8-channel streams (or less) so be sure to avoid configurations with streams that have more than eight channels. Figure 4-10: Routing Mac channels to physical outputs. Figure 4-8: Choosing an AVB configuration for the Mac. 7 For Recording to the Mac, route desired physical inputs on your MOTU interface to output streams. 4 From the Sample Rate menu (Figure 4-7), choose the desired sample rate. Currently, the Mac only supports 48, 96 and 192 kHz sample rates.
Figure 4-12: Routing streams from your MOTU interface to the Mac. AVB stream and channel counts Each MOTU AVB stream is a group of eight audio channels. While testing is on-going, OS X AVB performance varies with different Mac models. Models such as the Mac Pro (late 2013) are able to handle eight streams (64 channels) in and out simultaneously, for MOTU interface models that support eight streams. (Check motu.com/avb for a summary of supported stream counts for each MOTU interface model.
A TYPICAL 8A SETUP Here is a typical 8A setup. This rig can be operated with or without a separate mixer. All mixing and effects processing can be done in the 8A itself, controlled from your laptop, tablet, and smart phone — or several devices simultaneously. 8A front panel Headphones Synthesizer Quarter-inch analog outs Mics Other outputs (stage monitors, surround monitors, etc.
AUDIO CONNECTIONS Here are a few things to keep in mind as you are making audio connections to your 8A interface. TRS quarter-inch analog inputs and outputs Quarter-inch analog inputs and outputs are balanced (TRS) connectors that can also accept an unbalanced plug. ☛ Quarter-inch analog outputs are not cross-coupled. Therefore, when connecting them to an unbalanced input, use a TRS plug with the ring disconnected. Not floating the negative terminal will short it to the sleeve ground and cause distortion.
ensures that audio recorded by DAW host software on a connected computer, or audio playing back from the DAW, will remain resolved to time code and won’t drift over time, even when restarting or cueing the source time code. ☛ Depending on the stability of the incoming time code, it may take a few seconds for your interface to lock to the time code. The more stable the incoming time code, the faster the lock-up time.
3 Click the Become Clock Master button below the Clock Mode menu. Now, all other MOTU AVB devices on the network are resolved to this device. SYNCING MULTIPLE AVB AUDIO INTERFACES CONNECTED TO A MAC There are several options for clocking multiple AVB audio devices connected to the Mac: ■ You can resolve them to an external clock source (like word clock, if available). ■ You can create an aggregate device, as usual.
Part 2 Using the 8A
CHAPTER 5 Presets OVERVIEW AUDIO INTERFACE Because of its advanced, extensive feature set, the 8A can be used for many different purposes. This chapter discusses common use cases and their corresponding device presets, to help you use the hardware for your needs. Choose the Audio Interface preset to use the 8A as a standard Thunderbolt, USB or iOS audio interface. Hardware inputs and outputs are accessible from your computer or iOS device.
STAND-ALONE MIXER INTERFACE + MIXER Choose the Stand-alone mixer preset to use 8A as a mixer. Doing so routes all physical inputs to the mixer, with the mixer’s main mix bus and monitor bus going to Analog Outs 1-2 and the Headphone output, respectively. Choose the Interface + Mixer preset to use the 8A as both an audio interface and mixer, simultaneously.
LIVE RECORDING WITH MONITOR MIXING Choose the Live recording with monitor mixing preset when you are tracking in the studio. The setup is pretty much the same as for the “Interface + mixer” preset shown in Figure 5-3 on page 50, except that aux busses are routed to the 8A’s analog outs (in consecutive pairs) for independent monitor mixes. All physical inputs on the interface are routed to both the computer (for recording) and the Main Mix and Monitor busses in the mixer (for near-zero latency monitoring).
OPTICAL CONVERTER Choose the Optical converter preset if you would like the 8A to serve as a multi-channel digital-toanalog or analog-to-digital converter connected to another device equipped with an optical port. This preset sends optical inputs to the 8A’s analog outputs; conversely, analog inputs are routed to the optical outputs. For example, if you have another MOTU interface equipped with optical, you could connect its optical output banks to the 8A’s optical input banks.
The Front Panel LCD CHAPTER 6 OVERVIEW HEADPHONE VOLUME KNOB The front panel LCD displays level meters for all analog inputs and outputs and activity indicators for optical I/O. The LCD also provides several menus that provide status information and basic hardware settings. The headphone volume knob (Figure 6-2) is a push-button digital rotary encoder. Push the knob for the features discussed below. Level meters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Main Menu Push the up/down arrow buttons to scroll through the menu settings in the LCD. Settings menu The Settings menu provides access to basic hardware settings. Push SEL to enter the selected sub-menu or to select the currently highlighted parameter. Setting What it does Clock Mode Sets the digital audio clock source for the device. Push BACK to go to the parent menu. Sample Rate Sets the sample rate for the device.
CHAPTER 7 Working with Host Audio Software OVERVIEW RUN THE WEB APP The 8A provides multi-channel audio input and output for Core Audio compatible audio applications on the Mac and ASIO or Wave compatible applications on Windows, including MOTU’s Digital Performer and AudioDesk, Apple’s Logic Pro and GarageBand, and other third-party software applications such as Ableton Live, Avid Pro Tools, Cockos Reaper, Propellerhead Reason, Steinberg Cubase and Nuendo, Cakewalk SONAR, PreSonus Studio One, Bitwig, a
CHOOSE THE MOTU PRO AUDIO DRIVER Once you’ve made the preparations described so far in this chapter, you’re ready to run your audio software and enable the MOTU Pro Audio driver, which allows your host software to use the 8A as an audio interface.
Monitoring through the 8A If you don’t need to process a live input with plug-ins, the easiest way to avoid monitoring latency is to disable your DAW’s live monitoring feature and instead use the digital mixer in the 8A to route the input directly to your outputs. For details, see “Mixing tab” on page 16. The mixer in the 8A even provides zero latency effects processing (EQ, compression and reverb), which can be applied to the signal.
Adjusting buffer size on Mac OS X Under Mac OS X, audio I/O buffer size is handled by the host audio application (not by the 8A’s Core Audio driver). Most audio software applications provide an adjustable audio buffer setting that lets you control the amount of delay you’ll hear when monitoring live inputs or processing them with software plug-ins. Here are a few examples. Figure 7-4: In Logic Pro, go to the Audio Driver preferences to access the Buffer Size option shown above.
Figure 7-5: When adjusting the buffer size to reduce monitoring latency, watch the ‘processor’ meter in Digital Performer or AudioDesk’s Performance Monitor. If you hear distortion, or if the Performance meter is peaking, try raising the buffer size. If you are at a point in your recording project where you are not currently working with live, patchedthru material (e.g. you’re not recording vocals), or if you have a way of externally processing inputs, choose a higher buffer size.
Specifying the number of computer channels In the web app Device tab (page 14), in the Computer Setup section, you can specify the number of computer channels for streaming audio to and from your host audio software. You might want enough channels to cover the following: ■ Physical inputs you want to record on your computer. ■ The physical outputs you want to send audio playback to. ■ Any audio streams going to and from the on-board mixer in your MOTU device.
Streaming computer audio to and from the on-board mixer In the Routing grid, you’ll see mixer inputs across the top of the grid, including Main, Monitor, Aux, etc. (item 11 on page 15). These are output busses from the 8A’s on-board mixer. To route one of these mix busses to your host computer software, click the grid at the intersection of the mix column and desired computer channel row. Now, the mix bus output will be routed to the computer via the channel you selected.
2 Set the other LTC settings as needed, as discussed in “Syncing to SMPTE time code (LTC)” on page 44, including the Computer Channel for LTC-to-MTC Conversion setting. 3 If you would like MIDI Time Code to continue to be generated, even after LTC stops being received, check Enable Jam Sync (Figure 4-14 on page 45). Otherwise, leave it unchecked. 4 Follow the directions for MTC (SMPTE) sync in your DAW software.
CHAPTER 8 Mixer Effects OVERVIEW Leveler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 This chapter provides further information about the effects processors available in the DSP mixer in the 8A. For basic mixer operation, see: The Leveler™, an accurate model of the legendary LA-2A optical compressor, which provides vintage, musical automatic gain control Mixing tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GATE All input channel strips provide a Gate module. Enabling EQ Each band has an enable/disable button (Figure 8-3), allowing you to enable as few or as many bands as needed for the channel strip. Figure 8-2: The Gate module. Enable/disable The gate silences the signal when the input signal’s level drops below the Threshold. The rate at which the gate responds, (opens to let signal through) is determined by the Attack parameter.
sculpting. The four-band EQ has been designed to be flexible enough to cover a broad range of applications. By adjusting Gain and Bandwidth together, you can emulate the smooth and musical character of classic analog EQ circuits, in which the Gain/Bandwidth dependency was dictated by the actual circuit design and electrical components used. COMPRESSOR All mixer input channel strips provide a compressor module.
the signal to 2 dB above the Threshold. When the input level goes above the threshold, the attenuation is added gradually to reduce distortion. The rate at which the attenuation is added is determined by the Attack parameter. Likewise, when the input level falls below the Threshold, the attenuation is removed gradually. The rate at which the attenuation is removed is determined by the Release parameter. Long Release times may cause the audio to drop out briefly when a soft passage follows a loud passage.
LEVELER The Leveler™ (Figure 8-7) provides an accurate model of the legendary Teletronix™ LA-2A® optical compressor, known for its unique and highly sought-after Automatic Gain Control (AGC) characteristics. Figure 8-7: The Leveler module. The Leveler is available on the Main Mix bus and all Group busses, including the Reverb bus. A model of an optical compressor An optical leveling amplifier works by shining a light on a photoresistor.
Enabling or disabling the Leveler The Leveler models the LA-2A so closely, it also models the time it takes for an actual LA-2A to “warm up” after it is turned on. Therefore, when you enable the Leveler, give it a moment to “settle” before you begin processing signals with it. Gain Reduction Gain Reduction (Figure 8-7) sets the strength of the signal sent to the AGC model. Makeup Gain Makeup gain (Figure 8-7) amplifies the output signal to make up for gain reduction.
setting represents the bottom frequency of the Mid band. The Ratio determines the length for each band specified in a percentage of the low frequency reverb time. DSP USAGE The DSP Usage meter (item #30 on page 18) shows how much of the available DSP processing power is currently being used by the mixer for the mix and for effects processing. If there aren’t enough DSP resources for all effects to be enabled on a channel, effects are disabled for that channel and all subsequent channels.
MIXER EFFECTS
CHAPTER 9 MOTU Audio Tools The MOTU Audio Tools application provides advanced audio analysis tools, which can be applied to a left channel input, right channel input, or both. Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Device menu. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Analysis menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Left/right input . . . . . . . . . . . . . . . . .
ANALYSIS MENU Choose the desired form of audio analysis from the Analysis menu (Figure 9-1). For details on each analysis pane, see the following sections of this guide. LEFT/RIGHT INPUT Choose the desired channel(s) you wish to scope from the Left Input and Right Input menus (Figure 9-1). These menus display the To Computer channels configured in the MOTU Pro Audio Control web app. The number of channels shown is controlled by the From device to computer setting in the Device tab.
View controls You can show and hide the FFT display and spectrogram as desired using the View controls (Figure 9-5). Pause button View menu Display options Figure 9-5: FFT view controls. View menu This menu provides various options for displaying the two input channels. View menu setting What it does Left Displays the left channel only. Right Displays the right channel only. Split Screen H Shows both channels side by side, with the screen split horizontally.
OSCILLOSCOPE Vertical controls menu The Oscilloscope (Figure 9-9) graphs the amplitude of an audio signal over time. Figure 9-7: The Vertical controls. In Zoom/Offset mode, Zoom sets the display zoom from 1x to 100x, and Pos sets the center amplitude of the graph. In Min/Max mode, Min and Max set the smallest and largest displayed amplitude. Spectrogram controls The Floor control (Figure 9-8) sets the amplitude threshold for the spectrogram display, from -144 dB up to 0 dB.
View menu The View menu (Figure 9-10) lets you choose how to display the audio channel(s) being displayed.
Type I recognition provides the most stable display of the waveform. It is the most resistant to change. Louder transients, such as those produced by a snare drum, are not displayed inside of the waveform window. Type I is best for observing the shape of a signal produced by a synthesizer or observing the tone of a guitar through a chain of pedals. Type II recognition is less resistant to change. It will include loud transients within the waveform recognition window.
Trigger modes The Trigger menu (Figure 9-12) provides four modes: Trigger indicator re-arms the trigger. When the Trigger mode is None, clicking on the Trigger indicator has no effect. Trigger mode What it does Measurement information You can view detailed information about a particular time range by using the measurement bars (Figure 9-9). None The Trigger is not active; this is the default mode. The incoming audio signal will be displayed continuously as audio is received.
snare hit, as you make adjustment the compressor, you can see the transient waveform change the next time the Oscilloscope triggers. For compression, this can be particularly useful for balancing the effect of the attack on the transient, relative to the decay portion of the waveform. Conversely, you can see the effect of the threshold setting directly on the decay portion, relative to the attack. In effect, you can see as well as hear the results of your compression adjustments.
X-Y PLOT The X-Y Plot window (Figure 9-13) graphs the amplitude of a stereo audio signal on a twodimensional grid. For each unit of time (i.e., each sample), the amplitude of the left channel is displayed on the x-axis and the amplitude of the right channel is displayed on the y-axis. A thick white vertical line marks where left channel amplitude equals zero; a thick white horizontal line marks where right channel amplitude equals zero (Figure 9-13).
View controls The View controls (Figure 9-14) provide several options for the X-Y Plot display. Pause button Figure 9-14: View controls. Pausing the display The Pause button in the upper right corner of the View section (Figure 9-14) allows you to freeze the display at any time. To resume, click the button again. The level meters will remain active while the display is paused.
When warp is positive, they contract towards the origin (center of the grid). When warp is negative, they expand away from the origin. The further the warp value is from zero, the greater the effect. Figure 9-17: The Persistence controls. Using the X-Y Plot The X-Y Plot helps you “see” the width of the stereo field of a mix (Figure 9-18). It also helps you determine if a mix has issues with polarity, as follows: Length Length (Figure 9-17) sets the number of recent samples to show on the plot.
PHASE ANALYSIS The Phase Analysis window (Figure 9-19) graphs frequency versus phase difference versus amplitude of a stereo signal on either rectangular or polar coordinates. View controls The View controls (Figure 9-20) provide several options for the Phase Analysis display. Pause button In rectangular coordinates, the vertical axis represents frequency, and the horizontal axis represents the phase of the left channel minus the phase of the right channel (measured in radians).
Line/Scatter Choose either Line or Scatter from the menu in the View section (Figure 9-20) to plot each data point as either a single pixel or as a continuous line that connects each frequency data point to the next, as shown below in Figure 9-15. Rectangular/Polar Choose either Rectangular or Polar from the menu in the View section (Figure 9-20) to control how audio is plotted on the Phase Analysis grid.
Horizontal and vertical controls The Horizontal and Vertical controls (Figure 9-24) let you scale each axis of the grid and offset its zero point. Click and drag the values up or down to set them, or double-click to return to the default value. There are two modes for the controls: Zoom/Offset and Min/Max. To change the mode, use the menu shown in Figure 9-24. Figure 9-24: Setting the Horizontal or Vertical control modes. In Zoom/Offset mode, Zoom scales the axis. Pos moves the zero line.
outside the critical frequency range of the instrument being recorded, you can avoid phase problems among the mic signals. Tuning PA systems The Phase Analysis window can also be used to troubleshoot and tune PAs and sound reinforcement systems by placing microphones in strategic locations, comparing the two signals in the Phase Analysis grid and looking for phase issues at various locations.
MOTU AUDIO TOOLS
CHAPTER 10 Networking OVERVIEW The Audio Video Bridging (AVB) network port on the 8A opens up a world of possibilities for creating expanded, customized audio network systems. About AVB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MOTU’s AVB implementation . . . . . . . . . . . . . . . . . . . . . . . . Networking examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A quick guide to networking . . . . . . . . . . . . . . . . . . . . . . . .
■ Long cable runs — a single AVB network connection can run up to 100 meters with a standard copper wire CAT-5e or CAT-6 cable. Fiber-optic cable runs can be much longer. With multiple switches, you can create a network that covers very large distances, if necessary. You can use up to seven “hops” (switch-to-switch connections).
Personal studio expansion Let’s say you have a 8A next to your computer. You could add an 8M interface and position it across the room, near your drum kit, for placing up to 8 mics on the drums. All the mic cabling is kept near the drums, and you have one simple, clean network cable running back to your computer system. Despite the distance, the two interfaces operate as a seamless system, controlled from your computer or iPad.
Large-scale venues With long cable runs and industry standard networking infrastructure, MOTU AVB systems are well-suited for large-scale commercial installations such as arenas, stadiums, theme parks, clubs, casinos, houses of worship, broadcast facilities, schools, universities, and so on. Audio streams can travel long distances with submillisecond latency through as many as seven switches. Audio can be distributed from a centralized location to anywhere in the venue.
■ To add computers to the network, connect them to any interface using Thunderbolt (which offers the highest possible channel counts). If Thunderbolt is not available, use USB. ■ A computer can be connected to the network through its Ethernet port, but only for the purposes of running the web app on the computer for command and control over the network. (In this scenario, you won’t be able to stream audio to/from the network from the computer.
out. If the computer is connected with USB 2.0, performance will vary, depending on the sample rate and other factors. DEVICE PRESETS AND AVB STREAM CONNECTIONS When you save a preset for a MOTU device (item 7 on page 12), any AVB stream connections that it has established with other devices on the network are now included with the saved preset.
Part 3 Appendices
APPENDIX A Troubleshooting Some or all of my MOTU interface inputs and outputs are not available in my host audio software. Make sure that the inputs and outputs are enabled in the Device tab (“Device tab” on page 12) and routed to and from the computer in the Routing tab (“Routing tab” on page 15). For details, see “Making inputs and outputs available to your host software” on page 60. A quick and easy way to do this is to choose the Audio Interface preset from Quick Setup (item 10 on page 12).
Connecting or powering gear during operation... It is not recommended that you connect/ disconnect, or power on/off devices connected to the 8A while recording or playing back audio. Doing so may cause a brief glitch in the audio. CUSTOMER SUPPORT We are happy to provide complimentary customer support to our registered users. If you haven’t already done so, please take a moment to register online at MOTU.com, or fill out and mail the included registration card.
APPENDIX B Audio Specifications Line Out Connector Type 1/4” Female, TRS Balanced, tip hot Output Impedance 100 ohm Per leg Dynamic Range 123 dB A-weighted THD+N -110 dB (0.0003%) -1 dBFS, Unweighted, 1 kHz Frequency Response +0, -0.1 dB, 20 Hz/20 kHz Ref.
APPENDIX B: AUDIO SPECIFICATIONS
APPENDIX C Mixer Schematics MONO INPUT CHANNEL 99
STEREO INPUT CHANNEL + 100 APPENDIX C: MIXER SCHEMATICS
GROUP BUS + 101 APPENDIX C: MIXER SCHEMATICS
MONITOR BUS + 102 APPENDIX C: MIXER SCHEMATICS
APPENDIX D Updating Firmware MOTU periodically posts firmware updates for the 8A. These updates may include bug fixes, enhancements, and new features. Updates are posted on MOTU’s servers. If your computer or Wi-Fi device has access to the internet, the MOTU Pro Audio Control app notifies you as soon as an update is made available. Otherwise, you can check motu.com/avb periodically for the latest firmware update.
5 Scroll down to the bottom and click Update from File. 4 Click Update All Interfaces Now. 6 Locate the file on your hard drive and click OK to start the update. 7 Follow the on-screen instructions. 8 IMPORTANT: disconnect the Ethernet cable from your MOTU interface after you complete the update, unless it's connected to a MOTU AVB switch or other AVB-aware switch. If so, you can leave it connected.
APPENDIX E OSC Support Open Sound Control (OSC) is a protocol for communication among computers and other multimedia devices that is optimized for modern networking technology. MOTU AVB audio interfaces support OSC, which provides remote control of all device settings and mixer controls from any OSC-enabled controller. For further details about remote control through OSC, along with complete documentation for the MOTU AVB OSC API, visit: http://www.motu.
APPENDIX E: OSC SUPPORT
Index 24-bit optical 10 2x SMUX mode 13, 44 8A expansion 34 setup example 43 specifications 97 summary of features 23 A Ableton Live 55, 56 ADAT optical 10 connecting 44 settings 13 Analog inputs/outputs 44 making connections to 44 Apple Garage Band 56 Logic Pro 56 ASIO driver 56 monitoring 57 Attack Compressor 64, 66 Audio interface preset 49 Audio Tools 71 AudioDesk 25, 31, 55, 56 Aux Mix Target 17 Aux Mixing tab 17 AVB audio interface operation 23 Ethernet explained 87 Input/Output Banks 13 interface op
clock source 55 sample rate 55 LTC Input Source 14 Setup 44 to MTC conversion 61 M Mac OS X 55 input and output names 60 system requirements 27 Mac Virtual Entity 40 Makeup gain 68 Meters prefader 18 MIDI Time Code 14, 61 Mixer accessing 16 aux bus 20 connecting 43 effects 63 group bus 21 input channel strip 18 main mix channel strip 19 Monitor channel strip 19 overview 16 Reverb bus 21 schematics 99 Setup 13 stand-alone operation 63 Mixing tab 16 MOTU Audio Tools 71 AudioDesk 56 AVB Installer 29 AVB Switc
class compliance 29 installing drivers 29 V View Personal Mix 17 W Wave driver 56 WDM (Wave) Driver 30 Width reverb 69 Wi-Fi setup 39 Windows shortcut 31 system requirements 27 WDM (Wave) driver 30 X X-Y Plot 79 109 I N DEX
I N D E X