This article outlines important details regarding using Apollo X Rack:
System sleep is compatible with the latest Apollo Thunderbolt software. However, disabling sleep when using DAW software is generally recommended. For optimum results when using Apollo with DAW software, follow these guidelines:
- Disable sleep:
On Mac: Open the Energy Saver panel within System Preferences* and drag the “Computer Sleep” slider (if present) to “Never” (the far right position).
On Windows: Go to Control Panel > Power Options > Change Plan Settings and select "Never" from the "Put the computer to sleep" menu(s).
- Before sleeping the system, quit any DAW software using UAD plug-ins.
- If UAD-2 Satellite FireWire is connected, system sleep MUST be disabled. Sleep is not compatible with UAD FireWire devices (UAD-2 Satellite Thunderbolt is compatible with system sleep).
*To access System Preferences, click the Apple icon in the macOS Menu Bar (upper left of screen) then select the application from the drop menu.
Quit audio software before disconnecting Apollo
- Important: For optimum results, quit all audio software applications (DAWs) that are using Apollo and/or UAD plug-ins before disconnecting Apollo from the computer.
- It's safe to leave the Console and/or UAD Meter & Control Panel applications open when disconnecting Apollo.
- Although Thunderbolt has much higher data bandwidth compared to FireWire 800 (dual 10 Gigabit lanes for Thunderbolt 1 versus 800 Megabits for FireWire 800), it is still possible to run out of Thunderbolt bandwidth. This can occur when very high-bandwidth Thunderbolt peripherals such as high-performance RAID storage arrays, multiple Thunderbolt and/or 4K displays, and similar devices are connected in the same Thunderbolt chain.
- Bandwidth considerations are especially a factor at high session sample rates.
Using UAD-2 Satellite (FireWire model) with Thunderbolt
Note: This section applies to the UAD-2 Satellite FireWire model only. It does not apply to UAD-2 Satellite Thunderbolt.
- If UAD-2 Satellite (FireWire model) is connected, system sleep MUST be disabled. Sleep is not compatible with UAD FireWire devices.
- When UAD-2 Satellite is connected (via a FireWire port on the computer or the Apple Thunderbolt to FireWire Adapter) to the same system as a Thunderbolt-connected Apollo, the following conditions apply:
1. UAD plug-ins in the DAW loaded on UAD-2 Satellite stream via FireWire, while those loaded on Apollo stream via PCIe.
2. FireWire tuning with the UAD Bandwidth Allocation parameter is applicable for UAD plug-ins running on UAD-2 Satellite. Since UAD plug-ins in the DAW that are loaded on Apollo still stream via PCIe in this configuration, FireWire tuning is applicable only for those UAD plug-ins running on UAD-2 Satellite.
3. A minimum processing buffer of 512 samples for UAD plug-ins in the DAW applies for UAD-2 Satellite.
- Note that Realtime UAD Processing is always available for Apollo's inputs via the Console application, regardless of configuration (even when DAW I/O buffers are set to high values and/or when UAD-2 Satellite FireWire is connected).
Sample Rate Changes
- For optimum results when using Console without a DAW, perform sample rate changes within the Console application.
- For optimum results when using a DAW, perform sample rate changes within the DAW itself.
- For optimum results when Apollo Twin's current sample rate is different from the sample rate set within a DAW session, change Apollo Twin's sample rate within Console to match the sample rate of the DAW session before loading the DAW session.
4x Sample Rates Support
- Console's AUX 2 is unavailable at sample rates of 176.4 kHz and 192 kHz
- Multi-unit cascading is unsupported with sample rates of 176.4 kHz and 192 kHz
- Apollo uses DSP and memory for its internal mixer engine. Therefore, the UAD gauges show some idle resource usage even when UAD plug-ins are not loaded.
- As compared with UAD v7 software, idle UAD resource usage is increased slightly with UAD v8 due to increased channel counts in the newer software.
- When logged into the computer under an account that does not have administrator privileges, saving UAD preset files via the UAD Toolbar (via the small folder icon below each UAD plug-in interface) will result in an "Unable to save preset file" dialog. If this occurs, either log in with an administrator account, or use the DAW's preset management tools.
- When loading and saving UAD presets within Console 2, using Console 2's improved preset management tools are recommended instead of the UAD Toolbar.
External Word Clock
- To set Apollo to sync to external Word Clock, the setting must be made within Console. If the setting is changed from within the DAW's control panel, the change may not actually be activated even if the DAW indicates the setting is changed.
Important: UAD plug-ins within Console use DSP differently than when used within a DAW. To maintain the lowest possible input latency for Realtime UAD Processing, UAD plug-ins on a single Console input channel strip must fit on one DSP core (or two cores if Channel DSP Pairing is enabled). This is why the “DSP resources were exceeded” message can appear when stacking DSP-intensive UAD plug-ins within an input channel strip, even if the UAD meters indicate DSP resources are still available.For related information, review the Managing DSP Resources article.
- Loading Console sessions from differing Apollo hardware models allows the session to be opened as offline.
- Console sessions (and Console Recall plug-in sessions) created in Apollo Thunderbolt software cannot be loaded with Apollo FireWire software and vice-versa.
- Console Session files (configuration presets) saved within Console will not be saved if the "/" (forward slash), "\" (back slash), or "?" (question mark) characters are in the filename. Avoid these and other special characters when saving Recall files.
DAW Use Notes
What is the lowest hardware buffer setting I can use with Apollo for stable operation?
The audio interface hardware I/O portion of Apollo can run at any hardware buffer setting that is stable within the DAW itself. Results may vary as a result of how much the DAW session stresses the computer system. This can be influenced by:
- How many processor-intensive native plug-ins (such as virtual instruments, convolution reverbs, etc.) are in the session
- Track count and sample rate
- Processor speed and overall power of the computer
When UAD-2 Satellite (FireWire model) is connected to the system, UAD plug-ins used within the DAW run at a 512 minimum buffer size in order to operate reliably. Apollo’s dynamic buffering enables lower hardware I/O buffer settings (256, 128, 64 etc.) while maintaining a stable 512 buffer for UAD plug-in processing in the DAW.
The buffer size for UAD plug-ins used within the DAW is equal to the DAW’s hardware I/O buffer setting. Additionally, LiveTrack mode can be used with Thunderbolt (except when UAD-2 Satellite FireWire is connected) which lowers latency even further with UAD plug-ins used within the DAW.
Of course, for the lowest possible latency when running UAD plug-ins on live inputs, we recommend using the included Console application to take advantage of Apollo’s unique Realtime UAD Processing feature, where DAW I/O buffering does not apply.