QLab
QLab is a cue-based multimedia playback software application for macOS, designed primarily for creating and controlling sound, video, lighting, and show control cues in live theater productions and entertainment events.[1] Developed by Figure 53, a small software company based in Baltimore, Maryland, QLab enables users to sequence and trigger multimedia elements with precision, supporting formats such as audio files, video clips, MIDI commands, and network protocols like Art-Net for lighting integration.[2] It is widely adopted in professional settings, from community theaters to Broadway shows, due to its reliability, flexibility, and intuitive interface that allows for complex cue lists and real-time adjustments during performances.[1] The origins of QLab trace back to 2004, when its co-founders, Christopher Ashworth and Jesse Kriss, developed the initial version (0.1) as a side project to address the lack of suitable Mac-based playback tools for theater sound design.[3] The software debuted in a production titled Theatre of a Thousand Juliets in January 2005, marking its first practical use in live performance.[4] Early releases, such as QLab 0.9 in February 2006, were offered for free and focused on core sound cue functionality, quickly gaining traction in the theater community for filling a market gap in accessible, high-quality playback software.[4] By 2006, Figure 53 formalized the project with paid "Pro" versions, introducing advanced features like multi-channel audio output and MIDI support, which expanded its capabilities beyond basic audio to include show control elements.[4] Over the years, QLab has evolved through multiple major versions, with QLab 4 adding lighting control via the Art-Net protocol and QLab 5 introducing enhancements like spatial audio support in version 5.5 for object-based sound design.[5] Maintained by a small team of about 20 engineers, artists, and designers at Figure 53,[6] the software emphasizes user-friendly tools for professionals, including remote control options via iOS apps and integration with Open Sound Control (OSC) for networked cueing.[2] Today, QLab is used in over 100 countries and is considered an industry standard for cue playback in live events, praised for empowering audio engineers and technicians to handle diverse production demands efficiently.[2]Development and History
Origins and Early Development
Figure 53, a software company based in Baltimore, Maryland, was founded in 2006 by Chris Ashworth to create tools for live theater, with QLab emerging from an earlier side project started in 2004 and developed by Ashworth and Jesse Kriss. The initial version, QLab 0.1, was released in December 2004 and debuted in the production Theatre of a Thousand Juliets in January 2005, aimed at overcoming the shortcomings of contemporary audio playback software, such as rigid CD players and basic sequencers that hindered dynamic sound cue management in performances.[7][8][3][4] Earlier free versions, such as QLab 0.9 in February 2006, provided core audio cue sequencing capabilities that allowed theater technicians to organize and trigger sound files with precise timing and fades. QLab 1.0, released in late 2006 for Mac OS X, introduced paid "Pro" versions with advanced features like multi-channel audio output and MIDI support, marking a shift toward software-driven control in live events.[4] The software gained early traction among small theater companies and independent sound designers, who shared it via professional mailing lists; this adoption reflected a broader industry movement away from expensive, proprietary hardware toward cost-effective, flexible Mac-based solutions for cue playback.[8] A significant early milestone came with QLab 2.0 in February 2009, which introduced non-destructive editing for audio waveforms—enabling adjustments without altering original files—and basic MIDI support for integrating with external devices, solidifying QLab's role in comprehensive show control workflows.[9]Major Version Releases
QLab 3, released in 2013, marked a significant overhaul of the software's multimedia capabilities.[10] The version featured a completely rebuilt video engine, enabling advanced features such as surface creation for multi-display setups, edge blending, corner pinning, built-in masking, and 3D rotation for more precise projection mapping and visual effects.[10] It also introduced support for Open Sound Control (OSC), allowing QLab to send and receive OSC commands for enhanced integration with other software and hardware in live environments.[10] Additionally, the launch coincided with the introduction of the QLab Remote app for iPad, providing wireless remote control of cues from mobile devices.[10] In 2016, QLab 4 expanded the software's scope beyond audio and video into lighting control.[11] The key addition was the Light cue type, which supports DMX512 protocol for direct control of lighting fixtures using Art-Net and sACN network protocols, enabling seamless integration of lights into cue lists without external hardware.[11] This release transformed QLab into a more comprehensive show control tool, suitable for full productions involving multiple media types.[11] QLab 5, launched in 2022, focused on collaboration and modern hardware optimization.[12] It introduced real-time multi-Mac collaboration, allowing multiple users on separate computers to edit the same workspace simultaneously over a local network, streamlining team-based show preparation.[13] The video engine was rewritten to use Apple's Metal API, improving performance, efficiency, and future-proofing for newer macOS versions and Apple Silicon processors.[13] Object audio support was added, permitting immersive spatial audio routing and mixing directly within QLab, with visual tools for positioning sound sources.[13] Enhanced timecode chasing capabilities allowed cues to trigger mid-execution based on incoming timecode, with improved options for synchronization in complex shows.[13] Following the 2022 release, the QLab 5.5 series in 2025 brought refinements to audio and compatibility features.[14] Version 5.5.6, issued on October 9, 2025, included audio object presets in the Paste Cue Properties tool for quicker setup of spatial audio configurations, as well as new instrument definitions such as for the Arkaos MediaMaster 6 and various Chauvet fixtures to expand hardware compatibility.[5] It also addressed macOS Tahoe compatibility issues, fixing crashes during stage editing and layout problems with control buttons.[5] Across these major releases, QLab has trended toward greater cross-platform integration through protocols like OSC and Art-Net, alongside hardware-agnostic control that reduces dependency on specific devices, fostering more flexible live production workflows.[10][11][13]Software Structure
Cue and List System
In QLab, a cue represents the fundamental atomic unit of action within a show, designed to execute a single discrete event upon activation, such as playing an audio file, fading the level of another cue, or triggering a lighting change.[15] Each cue type determines the specific event it performs, with examples including Audio cues for media playback, Fade cues for parameter adjustments, and Light cues for DMX control integration.[15] Key properties of cues include duration, which for media-based cues defaults to the length of the target file (e.g., a 30-second audio clip runs for 30 seconds unless modified), and for Fade cues defaults to 5 seconds as set in workspace preferences.[15] Fade rates are configurable for smooth transitions in level, opacity, or position, while targeting specifies the object affected, such as a file path for media or another cue's ID for control actions, with each cue limited to one primary target.[15] Cues maintain state until their action completes, can be set to ignore redundant start commands, and support looping or partial playback to extend their behavior beyond a single execution.[15] Cue lists serve as hierarchical containers that organize cues into structured sequences, allowing users to group related actions for efficient management within a show file.[16] A cue list arranges its contents linearly from top to bottom, with the default firing order being sequential: starting one cue advances the playhead to the next upon completion or via manual continuation.[16] Parallel execution is enabled through Group cues, which bundle multiple cues and support modes such as simultaneous start, random selection, or playlist looping for varied performance needs.[17] Reordering within a list is non-destructive, permitting drag-and-drop adjustments without altering cue contents, and lists themselves can be nested or referenced across the workspace for complex hierarchies.[16] Workspaces, the top-level files in QLab, encapsulate multiple cue lists (along with optional cue carts for alternative organization), providing a complete show environment with global settings like output routing.[18] To support reliable production workflows, workspaces incorporate snapshots for version control, automatically creating timestamped backups that allow reversion to prior states for comparison or recovery of changes, with retention of up to 20 recent hourly saves plus daily archives.[5] For live performances, show mode functions as a locked state, disabling editing tools like the inspector and cue manipulation to prevent accidental alterations while preserving core playback functionality, requiring user confirmation for closure.[18] Cues and lists can be triggered through various mechanisms to suit manual or automated control. Manual activation occurs via the prominent GO button in the workspace interface or the spacebar keyboard shortcut, which starts the current cue and advances the playhead as configured.[19] Individual cues or entire lists support custom hotkeys and MIDI triggers assigned in the Triggers tab of the inspector, enabling hardware controllers like foot pedals or MIDI surfaces to fire specific actions.[20] Automated triggering is facilitated by timecode (LTC or MTC) or MIDI Show Control, where cues listen for incoming signals matching predefined times or messages, allowing synchronization with external timelines or devices.[21][22]Workspace and Editing Tools
The primary user interface of QLab consists of the cue list or cart view, toolbar, and inspector panel, enabling efficient construction and management of show files. The cue list displays cues in sequential order, allowing users to add, reorder, or delete them via drag-and-drop operations, while the toolbar provides icons for creating various cue types such as audio, video, or lighting. The inspector, accessible via keyboard shortcut ⌘I, appears below the cue list and features tabbed sections (e.g., Basics, Triggers, Settings) for detailed property adjustments on selected cues.[18][15] QLab supports multiple workspace views to suit different workflows: the timeline view, introduced for group cues, facilitates drag-and-drop timing adjustments, trimming, and slipping of child cues within a sequence for precise synchronization. In contrast, cart mode organizes cues into a grid of buttons for rapid, live triggering, with three configurable display sizes (small, medium, large) to optimize visibility during performances; users can switch between list and cart views using ⌘L or the View menu. These views enhance editing efficiency by allowing seamless transitions between planning and execution phases.[13][17] Editing tools emphasize pre-show preparation and batch operations. Audition mode, activated via ⌥Space for GO or ⌥V for preview, enables testing of individual cues or sequences on a secondary audio patch without disrupting live outputs, supporting rehearsal workflows. Multi-cue selection, achieved by holding ⌘ while clicking, permits batch edits across properties like duration, start/end times, or waveforms directly in the inspector or Time & Loops tab, streamlining adjustments for complex shows. The paste cue properties feature (⇧⌘V), known as "Fancy Paste," copies selected attributes from one cue to multiple targets via a checkbox interface, with presets for common sets like audio levels or audio objects added in the 5.5.6 update of October 2025.[23][5][24] File management in QLab prioritizes reliability and portability. Autosave occurs at user-configurable intervals from 5 to 600 seconds, as set in QLab Preferences, and includes optional snapshots of prior versions upon manual saves for version recovery. Workspaces can be bundled with embedded media files via File > Bundle Workspace, creating a self-contained folder for transfer to other macOS systems, ensuring compatibility without external dependencies. QLab 5 requires macOS Big Sur (11) or later and runs on any compatible Apple hardware.[25][26][27] Hardware integration supports live environments through USB DMX interfaces for lighting control, including models like ENTTEC DMX USB Pro, DMXking ultraDMX series, and the newly added DMXking MAX devices in QLab 5 updates. Multi-monitor setups are accommodated via video surface configurations in Workspace Settings, allowing up to multiple displays for extended output mapping in video-heavy productions. These features integrate with the cue hierarchy, where lists and groups organize playback sequences.[5][28][29]Licensing and Editions
Free and Paid Tiers
QLab 5 offers a free version that provides access to core functionality for basic show control, including unlimited cues and cue lists, making it suitable for entry-level sound design, simple video playback, and introductory lighting tasks. The free edition supports up to 2 audio output channels and 2 channels per audio file for basic playback, a single video output stage without multi-output capabilities, and up to 16 patchable DMX addresses across unlimited universes for lighting. Advanced features such as MIDI and OSC protocols, network cues, scripting, and full workflow tools are locked behind paid licenses but can be previewed in a 60-minute demo mode, which disables saving, copying, and pasting after expiration.[30] Paid tiers in QLab 5 are structured around functional licenses—Audio, Video, and Lighting—that unlock professional capabilities while including all pro features like MIDI/OSC integration, networking, show control protocols, and scripting automation. The Audio license expands to 128 output channels and 24 channels per file, enabling comprehensive audio effects, fades, and multi-track support. The Video license provides unlimited single- and multi-output stages, up to 1000 layers, and advanced effects including Syphon and NDI integration. The Lighting license removes the 16-address limit, allowing unlimited patchable DMX addresses and enhanced tools like color pickers for integrating lighting design. These licenses are available individually ($599 perpetual), in pairs ($1,099 perpetual), or as a full bundle ($1,399 perpetual), with all free features included.[30][31][32] Licensing models emphasize flexibility and accessibility, with perpetual licenses offering one-time purchases usable on up to two computers indefinitely, including discounts on future major versions, and rent-to-own options at daily rates ($8 for one feature set, scaling to $15 for full) that self-deactivate and provide store credit toward perpetual upgrades. Educational and site licensing (minimum 10 activations) are available at reduced rates for schools and large productions, respectively. Upgrade paths from QLab 4 provide trade-in credits—$299 for single licenses, up to $749 for bundles—allowing eligible v4 owners to transition to v5 while maintaining compatibility with v4.7 workspaces.[31][33][34] QLab 5 is exclusively compatible with macOS Big Sur (version 11) or later, with no support for Windows or earlier macOS versions, ensuring optimized performance on Apple Silicon processors such as M1, M2, and Ultra variants, which offer superior multi-display handling (up to 8 outputs on M2 Ultra) and efficiency for complex shows compared to Intel-based Macs. Minimum hardware includes 4 GB RAM for simple setups, rising to 8 GB or more for moderate complexity, with SSD storage recommended for reliable playback.[27][35]Upgrade and Compatibility Options
QLab users with valid licenses for versions 3 or 4 are eligible to upgrade to version 5, though QLab 5 licenses cannot authorize QLab 3; instead, QLab 4 licenses can be traded in for credit toward QLab 5 purchases, providing discounted upgrade paths based on the original license type.[31] For example, a QLab 4 audio, video, or lighting license trades in for $299 credit, a "pick two" license for $599, and a pro bundle for $749, allowing users to apply this value directly to equivalent QLab 5 modules or bundles, often reducing the net cost to the difference in pricing.[31] The upgrade process begins via the official account portal, where eligible licenses are deactivated upon trade-in and converted to store credit.[33] Automatic updates are facilitated through QLab's in-app checker, accessible via the QLab menu, enabling seamless installation of the latest releases such as version 5.5.6, distributed on October 9, 2025.[36] Previous versions remain available for download to address specific compatibility needs, ensuring users can maintain stable setups during transitions.[36] QLab 5 maintains full compatibility with macOS Big Sur (version 11) and later, including macOS Tahoe (version 26) starting from QLab 5.5, while QLab 4 exhibits incompatibility issues with macOS Tahoe and subsequent updates released after 2025, necessitating an upgrade for continued operation on newer systems.[27] Hardware integration is robust, supporting video outputs through Blackmagic Design devices like UltraStudio, DeckLink, and Intensity with a video license, as well as audio routing via Audinate's Dante Virtual Soundcard.[27] Migration from legacy versions is supported by QLab's native file import capabilities, where QLab 5 can directly open and convert workspaces saved in QLab 4, with similar forward compatibility from QLab 4 to QLab 3 files, though backward conversion is not possible.[35] For multi-Mac setups, the Bundle Workspace function consolidates media files into a single package for easy transfer and troubleshooting, minimizing issues in distributed environments.[37] Future-proofing in QLab emphasizes modern APIs and protocols, with the video rendering engine fully rewritten in version 5 to leverage Apple's Metal framework for enhanced performance on Apple Silicon and Intel processors.[38] Additionally, native support for NDI 5 enables efficient video and audio input/output over networks, accommodating evolving hardware advancements in live production workflows.[13]Core Playback Features
Audio Playback and Effects
QLab's audio playback capabilities center on its support for drag-and-drop integration of audio files, enabling users to load formats such as AIFF and WAV directly into cues via the Finder. With a Pro Audio license, QLab handles up to 24 channels per audio file and routes output across up to 128 channels, facilitating complex multi-channel setups. Looping is configurable through the Time & Loops tab, where users set finite play counts or enable infinite repetition, while slices allow playback of specific file sections with independent loops. Fades are managed via an integrated envelope system, supporting custom curves defined by control points for smooth in and out transitions. Sequential firing occurs within cues using slices or across lists with pre-wait and post-wait timings, achieving sample-accurate synchronization via the audio device clock for precise performance control.[39] Audio effects and routing in QLab provide extensive flexibility through unlimited audio output patches, configurable in Workspace Settings, which allow routing from cues to hardware devices. The cue matrix mixer enables per-channel level adjustments and panning, while the patch matrix mixer handles global routing to outputs, supporting matrix-based mixing for immersive environments. Effects chains utilize AudioUnit plugins, such as EQ, reverb, and compression, applied in real-time with adjustable order for dynamic processing during playback. Object audio, introduced in version 5.5, enhances spatial mixing by representing audio sources as movable objects on a map canvas, where positions relative to marks determine routing and fading to outputs, ideal for abstract or venue-specific immersive sound design.[39][30][14] Integrations extend QLab's audio functionality with support for networked protocols like Dante and AVB, enabling distribution of multi-channel audio over Ethernet to compatible devices for large-scale installations. Multi-channel support underpins immersive sound applications, routing up to 128 outputs to custom speaker arrays via the matrix mixers. Audition outputs, accessible through the Audition Window, permit isolated testing of cues on secondary devices or headphones without affecting the main system, streamlining rehearsal and troubleshooting.[40][41][42] Performance optimizations in QLab emphasize low-latency playback, particularly on Apple Silicon Macs, where native support reduces buffer sizes for responsive audio handling without choppy output, even under heavy effects loads. As of 2025, presets for levels and objects have been added via cue templates in Workspace Settings, allowing quick recall of mixing configurations to maintain consistency across sessions. These features ensure reliable operation in live environments, with buffer adjustments in Preferences balancing latency and stability.[27][25][43]Video Playback and Outputs
QLab's video playback capabilities center on video cues, which enable the reproduction of pre-recorded video files or still images stored on the host Mac, with support for a wide array of formats including H.264, HEVC, ProRes, and HAP codecs for optimal performance in live environments. These cues allow for precise control over timing, scaling, positioning, and audio routing embedded within the video, facilitating full-screen playback or integration as image elements within layered compositions. Additionally, camera cues capture live video feeds from sources such as webcams, Blackmagic Design capture devices, Syphon virtual screens, or NDI network streams, while text cues generate styled text overlays using system fonts, all manageable within the same cue framework.[44] QLab supports up to 1,000 simultaneous video layers per output stage, enabling complex, multi-layered visuals without performance degradation on compatible hardware. Advanced rendering in QLab 5 leverages Apple's Metal graphics API for hardware-accelerated processing, ensuring efficient handling of high-resolution content and real-time effects.[44] Per-cue blend modes, such as alpha compositing, multiply, and screen, allow individual layers to interact seamlessly, creating sophisticated visual hierarchies. Chained effects further enhance flexibility, including masks for selective visibility, warps for geometric distortion, and projection mapping tools that adjust for surface irregularities via customizable geometry presets and edge blending. Text overlays can be dynamically applied to any layer, supporting animations and font styling to integrate titles or graphics directly into video streams. Video outputs in QLab accommodate diverse live production needs through NDI and Syphon protocols for low-latency network streaming to compatible receivers or applications, enabling distribution across multiple devices without additional hardware. Hardware integration includes support for Blackmagic Design devices via DeckLink or Intensity cards for professional SDI/HDMI outputs, alongside direct HDMI connections to displays or projectors. Multi-display setups allow routing to independent screens, such as monitors, projectors, or LED walls, with independent scaling and positioning per output. Picture-in-picture modes permit nested video windows within primary outputs for enhanced compositing in real-time shows.[44] Synchronization features ensure seamless integration of video with other elements, providing frame-accurate timing aligned to audio cues or MIDI timecode for precise live performance control. Looping options support continuous playback of segments or entire clips, with configurable start/end points, while fade in/out transitions offer customizable curves for opacity, volume, and geometry over specified durations, promoting fluid scene changes. These elements can be briefly grouped with audio cues for unified timing, as outlined in the core cue system.Control and Integration Features
Lighting and DMX Control
QLab provides comprehensive support for lighting control through the DMX protocol, enabling precise manipulation of stage lights and fixtures in live performances. The software implements DMX as a standard for transmitting control signals, where each universe comprises 512 channels with values ranging from 0 to 255 (corresponding to 0-100% intensity), updated approximately every 23 milliseconds via RS-485 serial communication over XLR or RJ-45 connectors.[45] To facilitate scalable setups, QLab supports unlimited DMX universes through network protocols such as Art-Net, allowing transmission over Ethernet or Wi-Fi without physical cable limitations per universe. Art-Net requires a compatible node device to convert network packets to DMX output. Additionally, QLab integrates with various USB DMX interfaces, including models like the Enttec DMX USB Pro Mk2, DMXking ultraDMX Micro, and Yarilo DMX PRO, which connect directly to a Mac for single or multiple universe output without additional hardware. These interfaces are configured in the Workspace Settings, with automatic detection recommended for USB devices to ensure compatibility.[45][46] Lighting control in QLab is cue-based, utilizing Light cues to set parameter levels for individual instruments, groups, or presets, with built-in support for timed fades, chases, and transitions. Fades can employ customizable intensity curves, such as linear, S-curve, or parametric shapes, to achieve smooth dimming or color shifts over specified durations. Chases are implemented through sequenced cues or Group cues with pre-waits, enabling dynamic patterns like rotating gobos or color cycles. Presets allow referencing states from prior cues (e.g., via "10 = cue A" syntax in the Lighting Command Language), streamlining complex shows by recalling multi-parameter configurations without redundant programming.[47][48] Central to instrument management is QLab's Light Library, an extensive global collection of hundreds of fixture definitions spanning over 70 brands like Chauvet DJ (including the EVE series such as EVE P-56FC), Altman, Martin, and ETC, with users able to add custom definitions via JSON files or requests to [email protected]. Definitions detail parameters like intensity, pan/tilt, color mixing, and gobos, ensuring accurate control for multi-attribute fixtures. The Lighting Patch Editor facilitates assigning these definitions to workspace instruments, mapping DMX addresses, and editing virtual parameters for simulation. Complementing this, the Light Dashboard offers real-time visualization and auditioning of lighting states in Live and Audition tabs, displaying levels in slider or tile views even without an active network connection, and supporting MIDI-mapped submasters for intuitive adjustments.[49][46][50] Effects in QLab extend beyond basic control to include color palettes for RGB/CMY mixing, programmable gobos for pattern projection, and intensity curves for nuanced transitions, all configurable within Light cues or the Dashboard. These features integrate seamlessly with video playback, allowing lighting states to synchronize with video cues through shared timelines or Network cues, enhancing multimedia productions with coordinated visual and luminous elements.[47][48] For live performances, QLab enables real-time patching and overrides via the Light Dashboard or OSC commands, permitting operators to adjust DMX assignments, park channels, or apply temporary levels without interrupting playback. This flexibility supports on-the-fly corrections, such as repositioning a fixture's address or boosting intensity during a show, while maintaining cue integrity.[46][50]Show Control Protocols
QLab supports integration with external systems through several standardized protocols, enabling automated show control in live performances. These protocols facilitate cue triggering, synchronization, and parameter adjustments across devices, allowing QLab to act as a central hub for multi-system coordination without requiring custom hardware beyond standard interfaces.[51][52] MIDI integration in QLab allows for cue triggering via mapped messages such as Note On or Program Change, which can be assigned to workspace controls like GO or individual cues through the Triggers tab in the Inspector. Parameter control is achieved by configuring MIDI Control Change or velocity-sensitive inputs to adjust elements like volume or playback speed, while device syncing occurs through responses to incoming MIDI messages for seamless interaction in real-time environments. This setup supports interactive performances by connecting QLab to MIDI keyboards, consoles, or lighting systems, ensuring precise timing without latency issues when using reliable interfaces.[51][53] OSC and Network cues enable sending and receiving Open Sound Control messages over TCP or UDP on local networks, supporting remote control from devices like iPad apps (e.g., TouchOSC) or software such as Max/MSP. These cues handle plain text commands for actions like/go or /pause, and facilitate timecode chasing by integrating with external timelines for synchronized playback. Network patches support multiple destinations, with fade options for interpolating values in OSC messages, making it suitable for wireless setups in theaters or installations.[52][54]
Other protocols extend QLab's capabilities further. MIDI Show Control (MSC) provides structured commands like GO, STOP, or RESET, using Device IDs to target specific systems and ensuring cue numbers match exactly for reliable execution. Linear Timecode (LTC) and MIDI Timecode (MTC) support broadcast timing, with LTC generated as audio signals on specified channels and MTC via MIDI ports, both configurable for frame rates like 30 fps non-drop to align with video or audio sources. QLab's API, primarily through its OSC dictionary and AppleScript support, allows custom scripting for advanced automation, such as programmatic cue manipulation or integration with external scripts.[53][55][56]
In practice, these protocols automate multi-system shows by syncing elements like audio cues with lighting changes, as seen in theatrical productions where QLab triggers DMX endpoints via MIDI or OSC while chasing timecode from a master clock. This integration is common in concerts and theme park attractions, where precise coordination prevents desynchronization during live events.