Logic Pro 9 TDM Guide
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Contents Preface 5 5 6 6 An Introduction to Using TDM Hardware in Logic Pro About Logic Pro TDM Support About the Logic Pro Documentation Additional Resources Chapter 1 9 9 9 11 TDM Audio Hardware and Drivers Choosing a DAE or Direct TDM Device DAE Settings Direct TDM Settings Chapter 2 13 13 14 15 15 About TDM How TDM Differs from Native Processing TDM Plug-ins Using TDM-Specific Functions Simultaneous Use of TDM and Other Hardware Chapter 3 17 17 18 19 ESB TDM and EXS24 TDM About the ESB TDM a
Preface An Introduction to Using TDM Hardware in Logic Pro Earlier Digital Audio Workstations (DAWs) took one of two approaches to audio signal processing: The use of dedicated hardware DSPs (such as in TDM systems), or the native processing capabilities of the computer CPU. Logic Pro enables you to use both your TDM system DSPs and the computer’s native CPU processing resources. The link between the DSP world of your TDM system, and your computer’s native CPU processing resources is ESB TDM.
About the Logic Pro Documentation Logic Pro comes with various documents that will help you get started as well as provide detailed information about the application. • Logic Pro User Manual: The onscreen user manual is a comprehensive document that describes the Logic Pro interface, commands, and menus and gives step-by-step instructions for creating Logic Pro projects and for accomplishing specific tasks. It is written for users of all levels of experience.
Apple Service and Support Websites For software updates and answers to the most frequently asked questions for all Apple products, go to the general Apple Support webpage. You’ll also have access to product specifications, reference documentation, and Apple and third-party product technical articles. • http://www.apple.com/support For software updates, documentation, discussion forums, and answers to the most frequently asked questions for Logic Pro, go to: • http://www.apple.
TDM Audio Hardware and Drivers 1 To use Logic Pro with your TDM system, you require Pro Tools HD 7.4 or later. This chapter covers the following: • Choosing a DAE or Direct TDM Device (p. 9) • DAE Settings (p. 9) • Direct TDM Settings (p. 11) Choosing a DAE or Direct TDM Device Selecting and activating a particular audio hardware device is done in the Logic Pro > Preferences > Audio > Devices pane. You can choose between the Core Audio, DAE, and Direct TDM tabs.
Note: You need to restart Logic Pro to activate the DAE. • Global Bit Depth pop-up menu: Choose between 16-bit or 24-bit playback and recording. Note: DAE does not allow the use of 16- and 24-bit files simultaneously. • PT HD Type pop-up menu: Defines the number of tracks for your Pro Tools HD system. Each menu item allows you to define the required number of tracks, based on the number of Pro Tools HD DSPs that you want to use (and actually have) in your system.
• Digidesign Hardware Setup button: Opens the Digidesign Hardware Setup window that contains all important system settings for your hardware. Note: The Process Buffer Range and ReWire Behavior parameters at the bottom of the Devices pane have no effect when DAE is active. Direct TDM Settings Activate Direct TDM if you want to use your computer CPUs to process Logic Studio instruments and effects, while also using the TDM features. • Enabled checkbox: Click to activate Direct TDM.
Depending on whether a mono or stereo region is played back, the Pan knob will behave as either a Balance or Pan control. If you play back a mono region when the Pan knob is centered, both channels of the audio channel strip will output the same signal level. Note: Universal Track Mode has limited routing capabilities, as it doesn’t allow separate handling of the left and right audio channels.
About TDM 2 Logic Pro allows you to use the TDM functions of Pro Tools HD systems. TDM is an abbreviation for Time Division Multiplexing—the time-interlaced transmission of multiple digital audio signals (or streams) through a single data bus. This bus system is physically isolated from the computer system bus, and runs between the individual TDM-capable (PCI or PCIe) cards. Up to 512 digital audio channels, each with 24-bit resolution, can be transmitted on the TDM bus.
• The TDM hardware determines the overall features of the system: number of tracks, number of TDM plug-ins that can be used simultaneously, number of inputs and outputs, and so on. See your Pro Tools system manuals for further information. • Stereo recordings require two tracks, and are recorded as two separate files. In Logic Pro’s Arrange window, a stereo recording is handled as two linked regions, which use two tracks. In the Sample Editor window, stereo recordings are displayed as a stereo file.
If you currently own any RTAS plug-ins, you should install the Audio Units equivalents for use in Logic Pro. Most plug-ins are available in several formats. If no Audio Units version is available on your RTAS plug-in installation CDs, visit the websites of the plug-in manufacturers. Using TDM-Specific Functions Note the following if you want to use your hardware’s TDM functions with Logic Pro.
The number of tracks may also be reduced if the connected systems access the same hard disk bus. This can be mitigated (resulting in an increase in the total track number) by using different hard drives for the various systems. For example, the audio data for a Direct TDM or Core Audio device, and a QuickTime movie are read from an internal hard disk, and audio data for a DAE device is read from an external FireWire hard disk.
ESB TDM and EXS24 TDM 3 Logic Pro allows you to use both your TDM system DSPs and the computer’s native CPU processing resources. The link between the DSP world of your TDM system and your computer’s native CPU processing resources is ESB TDM. ESB TDM uses your computer CPU to process one audio engine (Direct TDM), and the DSP of the TDM hardware to process another (DAE). This is done by using two different mixers in Logic Pro. The TDM Mixer uses the DAE to process TDM plug-ins.
The ESB TDM plug-in allows you to route up to eight audio channels of the DTDM Mixer in to the DSP-based TDM Mixer. This is similar to having a card equipped with a multi-channel digital output installed in the computer, and physically connected to a second multi-channel input module for your TDM system. ESB TDM routes digital signals via software within the computer, effectively replacing the audio card’s digital outputs and driver, the TDM audio interface, and the cables between them.
µ µ To insert the EXS24 TDM Click the top Insert slot of an aux channel strip in the TDM Mixer, and choose EXS24 TDM from the pop-up menu. To play the EXS24 TDM sampler inserted in the aux channel strip Select the corresponding aux track in the Arrange window. When the track is selected, you will be able to play and record the sampler instance. Subsequent insert slots in the aux channel strip allow the insertion of TDM effect plug-ins, for processing of the sampler’s output signal.
Depending on the number of required channel strip types, your DTDM Mixer could look something like this: This DTDM Mixer example features six audio channel strips, two aux channel strips, two instrument channel strips, and two stereo sums. The eight output signals of the DTDM Mixer example shown above are routed into the TDM Mixer. The DTDM Mixer output signals are received by the ESB TDM inputs—chosen as TDM aux channel strip input sources.
ESB TDM Mono and Stereo Handling Logic Pro handles ESB TDM mono and stereo channel settings separately. You can specify either a mono output channel (ESB 1–8), or a stereo output channel pair (ESB 1–2, 3–4, 5–6, and 7–8) in the DTDM Mixer. These can be individually selected as aux channel strip input sources in the TDM Mixer.
Logic Pro TDM Usage Tips and Tricks 4 This section provides tips and tricks that may be useful when using Logic Pro with TDM hardware. As a general working suggestion, you should avoid the simultaneous use of more than two audio engines in Logic Pro. The strain on the PCI bus can be problematic, resulting in a number of DAE error messages. Your first choice should be the DAE—in conjunction with Direct TDM. If necessary, choose DAE and Core Audio.
3 Open the project. You will be asked if you’d like it automatically converted to Direct TDM. Logic Pro loads the project into a DTDM Mixer, and checks if there is a channel strip available for every hardware channel. If not, a suitable number of channel strips is automatically created in the DTDM Mixer. This facility ensures that changes to the hardware in a given computer, or moving project data to another computer (with different hardware), will result in corresponding channel strip changes.
DAE and Direct TDM Bounce Strategies The easiest way to perform a stereo bounce is to choose File > Bounce (or use the Toolbar Bounce button or key command). This will open the Bounce dialog for outputs 1-2 of your primary audio device. It is recommended that you use the first output pair for main playback duties. Note: If you are using other output channel strips for primary playback duties, click the Bounce button on these channels.
