Broken, Unbroken

I’m delighted to say that the most recent 360 video in the Trinity360 series has now been released and can be seen below. The piece, titled Broken, Unbroken, was performed by Nick Roth, and the Cue Sax Quartet on Tuesday June 26th 2018 in various locations around Trinity College Dublin. Thanks again to SoundFieldTM Microphones for their sponsorship of the production.

In addition, here’s a short behind-the-scenes video about the production, which can be seen on the Soundfield website, here.

The logistics of acoustic spatial music performances are often quite challenging to deal with. While specific architectural features such as balconies can be an interesting creative opportunity, this site-specificity can also be problematic for repeat performances in other venues which may not have those specific features. More generally, devising a suitable layout for the spatially distributed performers and an audience, many of whom may be seated in a far from ideal position, is often far from straight forward. 360 video and matching spatial audio represents a significant opportunity in this regard, as in many ways it is the ideal medium to capture such performances. Eliminating a live audience allows for a far greater range of potential venues, and as a result, the musicians can be placed as close to the camera as desired. In some respects, a 360 video recording of a work of spatial music can be considered as a performance for an audience of one, thereby potentially overcoming many of the logistical challenges associated with this type of music.

360 video therefore allows for much more freedom in terms of the types of venues you can use, and also the way in which you position the musicians. As always however, we must carefully consider the relationship between the acoustic environment, and the types of spatial effects attempted in the composition, and investigating this issue was one of the principle goals of Broken, Unbroken. It contains four sections, each of which explore different spatial effects, and the piece was performed in its entirety in four, quite different locations (which were discussed in more detail in a previous post). This allowed for the comparison of the resulting recordings, and the choice of a location for each section that best suited the particular spatial effects implemented in each section.

The recording was captured using a single Soundfield ST450 MkII Ambisonic microphone, mounted just below the GoPro Omni 360 camera rig, as shown below. For the two exterior locations, a Rycote Windjammer and windshield was also used although for once, the Irish weather was nice and sunny with little to no wind.


For the opening section of Broken, Unbroken I wanted to experiment with large distances and mobile performers, which was really only possible in the wide expanse of Front Square. The main idea here was for the music to gradually emerge from the background ambiance of the location, as the performers move through the square and approach the camera. The music consisted of a short phrase which the musicians could improvise around and play from memory. Much like in the middle section of From Without, From Within the musicians are not synchronized in any way, until they finally all converge around the recording position. One of the surprising aspects of this section was how well the direction of each musician was maintained in the first order Ambisonic (FOA) recording, even at large distances (c. 120m). In contrast, FOA recordings made in indoor locations with significant reverberation can suffer from a distinct lack of directionality when the instruments are placed far away from the microphone.

The title of the piece, Broken, Unbroken, is a reference to the cori spezzati (meaning “split” or “broken” choirs) technique used by composers such as Adrian Willaert and Andrea Gabrieli in 16th century Venice. Here, the title refers to both this breaking of the individual musicians into distinct locations, but also the deliberate bringing together (or unbreaking) of the quintet in the second and third sections of the piece. Henry Brant used the term ‘spill’ to describe this effect of spatially separated instruments joining together to create an immersive, unified whole. The easiest way to achieve this is by simply having the instruments play in exact unison, or at least closely related harmonic intervals. One of the things I wanted to investigate in this piece was the extent to which this effect is influenced by the nature of the acoustic environment, and in particular the amount of reverberation. Overall, it appears that a strong sense of spill can be achieved in any location, and with any distribution of instruments, once they are all playing in strict unison. However, this effect is much less pronounced in exterior locations once they deviate from unison to any degree. However in more reverberant locations, such as the Anatomy Theatre in section 3, the effect still holds to an extent once the individual lines retain a close harmonic relationship.

A number of composers have attempted to create spatial trajectories by passing material between instruments, perhaps most famously the sustained chord passed between the brass instruments of three spatially distributed orchestras in Karlheinz Stockhausen’s Gruppen fur Drei Orchester (1955-57). This technique, which is in many ways an acoustic emulation of amplitude panning, is rather fragile however, as it relies on very precisely matched pitch and timbre, and a high degree of synchronization between the overlapping crescendo and decrescendo dynamic envelopes in each instrumental group. A slightly different implementation of this technique was therefore implemented in the fourth and final section of Broken, Unbroken using overlapping staccato note sequences which are embedded in a melodic canonic structure. In this way, circular trajectories are created through both the passing of these staccato sequences between consecutive instruments, and also the accenting of the specific pitches in the melodic canon.SCoreExtract-SecD-highlight

This was arguably the most effective section of the piece overall, particularly in the relatively dry acoustic of the Freeman library in which the musicians had clear sight-lines between each other and could maintain synchronization relatively easily. Once again however, in more reverberant locations such as the Anatomy Theatre, the overall reduction in directionality captured in the recording negatively impacted on the clarity of the spatial trajectories to a significant degree. This effect also worked quite well in the vertical arrangement of musicians in the Beckett Theatre balconies, however maintaining synchronization was naturally more difficult, even with a conductor.

Overall, the comparison of the recordings from each location indicates that the effectiveness of these different spatial effects is strongly influenced by the amount of reverb, and the distance of the performers from the microphone. While there has always been a relationship between the musical content, and the acoustic environment used for a performance, this is a particularly important consideration for this new medium of 360 video. Composers and sound engineers should therefore consider their choice of venue carefully when filming spatial music performances, and ensure that this choice supports the spatial effects implemented in the music. 

More details on this piece will be presented in a paper entitled ‘Recording & Composing Site-Specific Spatial Music for 360 Video’, which will be presented at the 146th Convention of the Audio Engineering Society, in Dublin, in March 2019.

Nick Roth is a prominent contemporary musician in Ireland and co-founder of the Diatribe record label. Upcoming projects include the Space I Installation for the European Space Agency (ESA), and numerous performances as detailed here.

Cue Saxophone Quartet is a talented and ambitious chamber group, composing, arranging, and performing music in contemporary, classical, jazz, and popular genres. More information about upcoming performances can be found here.

I would like to acknowledge the support of the Trinity College Visual and Performing Arts Fund for this performance, and also the support of SoundFieldTM Microphones in providing equipment for this project.

In addition I would like to thank Gillian Marron and Padraig Carmody from the Dept. of Geography, Siobhan Ward and the Steering Group for Old Anatomy from the School of Medicine, Michael Canney from the School of Creative Arts, and Austin Sheedy and Rua Barron from DU Players, for facilitating access to these different venues around the university.