In the realm of audio production, the transition from the controlled studio environment to the variety of live setup deployment choices poses a pivotal challenge. This challenge becomes particularly significant when working with SPAT Revolution and its ability to deliver to various speaker arrangement formats with various techniques. A paramount concern is ensuring a seamless translation of the carefully designed spatial composition, including positioning and automation, from the studio to a live environment.

Defining the reproduction strategy (Speaker system & panning technique)

While this article does not aim to delve deep into the subject of system design, it is worth discussing a significant challenge behind the ‘From Studio to Live’ journey. In essence, it’s about content creation, taking place in an ideal monitoring ‘sweet spot’, and live deployment, which invariably involves compromises and spread out audience coverage area. Notably, this discussion touches on the reproduction strategy to adopt, where the position-based family of panning techniques such as DBAP, KNN, and the more sophisticated WFS are our best friends for such live reality.

It is tempting to suggest, ‘Let’s surround our audience with a large number of speakers,’ and indeed, increasing the number of loudspeakers has the potential to enhance ‘resolution’, or, if you prefer, the accuracy of soundscape reproduction. However, for everyone to fully experience this heightened accuracy, we must ensure that each loudspeaker or loudspeaker array offers adequate coverage and sound pressure level (SPL). Ultimately, a reproduction strategy aligned with the artistic intent but conditional to a capable system stands as the key to achieving success.

The Role of Transcoders in SPAT Revolution:

Contemplating the use of transcoders, such as master transcodes, in SPAT Revolution for converting between speaker arrangements prompts inquiry. It’s crucial to note that these transcoders primarily facilitate the transcoding of ambisonic stream formats to channel-based speaker setups. Channel-based to channel-based transcoding serves as a matrix tool only, not a medium for down/up mixing from one speaker setup to another.

The construction of a SPAT Revolution soundscape

Understanding the components of the soundscapes in SPAT unveils essential elements to understand for a successful transition across systems:

Source Object (Position and parameters)

The foundation of the soundscape you are building is about manipulating all the source object properties. The efficacy of panning techniques and the reproduction system determines the experiential outcome. Adapting speaker arrangements and techniques in SPAT Revolution facilitates easy migration to diverse systems. This can be pretty much done ‘on the fly’.

Source Object Attenuation Model

The model, relying on source distance from the center reference point, influences amplitude and air absorption simulations. When employed, the protection zone establishes a pivotal threshold where our processing initiates the ‘simulated’ distance attenuation, influencing both amplitude and spectrum in the case of air absorption (minor high-frequency roll-off). This simulation aims to replicate our natural hearing experience in relation to distance. Overlooking this aspect while ‘scaling’ a mix can notably influence the resultant mix quality. By default, SPAT standard normalized arrangements set the distance threshold at 2 meters, aligned with the speaker line and typically extended to the farthest speaker in larger or non-normalized systems. Thus, this distance, spanning from the center reference point (0) to the protection zone’s boundary, defines the threshold. To illustrate, if this threshold is set at 10 meters and your source is 20 meters away, the distance has doubled, resulting in a loss of 6 dB per the physics principles. The drop factor ratio, a key source parameter, governs this 6 dB reduction. Notably, this concept adheres to a spherical nature and isn’t contingent on the speaker setup’s geometry. Consequently, appropriately scaling this factor in tandem with session setup alterations proves pivotal. This adjustment will impact the ‘direct/reverb omni ratio’ when utilizing SPAT’s room reverb engine.’

The Room’s Reverberation Model:

When applied to some or all audio source objects, the ‘room’ reverb settings play a central role in tailoring the mix to achieve the desired room ambiance. This adjustment typically occurs on-site, allowing you to mold the mix’s sonic character. However, challenges arise when transitioning from a rather acoustically inert or ‘dead’ room to a space with pronounced reverberation. In such instances, careful consideration is needed to either harmonize the reverb model with the new environment or judiciously omit or limit its use. A good starting point is typically changing the first reflections settings (Early and Cluster) and the overall reverb gain. Relocating from a studio setting to an open outdoor space presents a comparatively simpler scenario, as it offers a higher degree of control over acoustic characteristics.

Bringing It All Together

Now, having meticulously crafted your mix or artistic creation within the confines of the studio, the pivotal moment arrives: the transition to the live venue. Throughout the creative process, you’ve been fine-tuning your mix on a specific speaker monitoring setup, utilizing a set protection zone that emulates distance, and potentially crafting snapshots and automation using tools like DAWs or remote control applications such as QLab. As you establish a new speaker arrangement tailored to the venue, the transformation begins. The instant you actually apply this new arrangement into your mix session, SPAT Revolution springs into action, automatically initiating a scaling process. An alert marked ‘NEW SPEAKER ARRANGEMENT’ is announced, advising you that the selected new arrangement speaker distance differs from the previous one. Consider this: if your studio’s farthest speaker sat at a distance of 5 meters, and the new venue configuration extends it to 25 meters, SPAT Revolution will propose a scaling factor of 5. When accepted and applied, this factor cascades across multiple facets:

  • Each current source’s distance parameter
  • The protection zone, integral to the attenuation model
  • A distance scaling factor within the room output section dynamically impacting recalled snapshots, plugin-based automation, and incoming OSC messages.

And there you have it – a seamless integration of the new arrangement. This methodology seamlessly synchronizes with direction-based techniques, as it fundamentally maintains the consistency of angles that these techniques rely upon. Additionally, the protection zone, enriching the mix with its attenuation model, undergoes appropriate scaling. Consequently, all automation, snapshots, and remote communications harmoniously adapt to the new system’s scale, thanks to the dynamic scaling fostered by the distance scaling factor within the room output section.

Navigating Challenges and Conclusion

While the automated scaling works seamlessly with direction-based techniques, such as vector-based methods, it might not serve as a panacea for position-based approaches. In other words, this automatic scaling may not wield an all-encompassing solution if you’re employing position-based techniques, such as DBAP or the Wave Field Synthesis reproduction approach. The intricacies arise due to the unique geometry of the speaker arrangement, rendering it more complex than a mere distance-based scale factor. The alteration in the spatial relationship between the speakers and sources, as dictated by the new setup, can yield substantially different outcomes. It’s essential to note that this doesn’t imply a breakdown but signifies a distinct rendition of the audio.

In such cases, it may be strategic to consider the pre-production environment, and the in-studio monitoring system to be more aligned in reproduction technique and speaker setup geometry to the future venue system, such as with a scaled-down version.