A wide array of skills are required to thrive in the fast-paced world of live sound reinforcement. Presently, the primary method for sharpening these skills is to employ them with live performers within a venue complete with a substantial compliment of audio equipment. While this approach has proven successful, the current need for trained professionals has outpaced the supply of practitioners. Academic institutions often provide hands-on experience to student by gaining experience during internal events, or by hiring performers to provide a material for student to practice with. Both of these options provide advantages, but can be costly, provide limited training time, and can be stressful for students. The Virtual Sound Reinforcement Practice (VSRP) system proposes a solution to these problems, allowing participants to practice this skillset without the expense, pressure, and logistics currently required. The VSRP system combines multitrack audio and video playback and binaural rendering to recreate a realistic concert experience, while also offering users the ability to experiment, learn from mistakes, and provide real-time feedback. Most importantly, the system can be deployed in a small environment for a single user, without the need for extensive equipment or live performers, making the ability to practice more accessible. The current iteration of the system is built in Max MSP for multitrack audio playback and a basic mixer for manipulation by users via a control surface, as well as playing back synchronized HD video. Audio and video materials are taken from real sound checks and performances, with video showing the entire stage, often recorded from directly behind the mix position. This presentation is critical to system realism, as audio-only practice robs the user of the multimodal input provided in a real performance environment which can often cue critical events. Audio is presented binaurally using IRCAM’s SPAT5. In addition to the individual sources provided for users to mix, a stereo capture of the acoustic energy coming from stage is included, recreating both a realistic soundstage and the challenges of balancing acoustic and amplified elements, rather than simply presenting close, dry sources. Finally, the system operates in real time; the urgency in live mixing is reinforced through the lack of a pause button or ability to rewind. The final component of the VSRP system provides users with a framework for scaffolded practice. “Practice mode” provides users with reminders about critical events if not addressed within sufficient time. Expert mixers have provided example mixes, allowing the developers to estimate acceptable source levels and approximate expected reaction times for addressing changes within the mix. This informs an acceptable range of levels, with a surrounding buffer to account for varied tastes. Similarly, the average of experts’ response times provide a baseline for the system. Both of these targets are widened for novice or beginning users, and can be tightened to maintain a challenge for more advanced system users. In practice mode, a text display will alert a user if a significant event (e.g. a solo or entrance of a new audio element) has not yet been addressed or moved towards a suitable level. Text is displayed atop the video, near the location of the event, in order to reinforce the link between watching and listening. Following practice sessions, users may engage in an evaluation, where feedback is provided only after the mix has been completed. As a user advances in difficulty level, sound checks will provide the familiarization process with longer performance segments as evaluations.
