Hamer Hall (Melbourne) – Melbourne Symphony Orchestra
I’m very excited to begin my writing about venues and their acoustics with what is probably my new “hometown” venue – Hamer Hall in Melbourne, Victoria (Australia). After moving from Brisbane at the beginning of 2018, I’ve only managed to see a handful of shows in what has turned out to be a hectic start to life in Melbourne. A somewhat impulsive decision attend a Melbourne Symphony Orchestra performance has given me the opportunity to do some research and write this piece.
Performance Details
Date: Saturday 1st September 2018
Venue: Hamer Hall, Melbourne, Victoria.
Performance: Vine & Holst – Melbourne Symphony Orchestra – Conducted by Sir Andrew Davis
Program: Symphony No.8, The Enchanted Loom (Carl Vine) and The Planets, Op.32 (Gustav Holst).
Seat: Circle A35
Venue Details
Layout: Shoebox, slightly fanned.
Capacity: 2500 over three tiers (Stalls, Circle and Balcony) [2]
Volume: 27,000m³ [1]
Looks
The first time I attended Hamer Hall, I remember being quite smitten with the “look” of the space, and I definitely still enjoy settling in amongst the warm copper tones. The smoother burnished metal styling of the newer rear wall and stage siding offers an understated contrast to the sandstone-like finish of the side wall and roof faceting. Overall, a quite natural and earthy feel is realised, which works particularly well with the orchestra, complementing the natural wood finish of much of the instruments.
Sounds
Based on my admittedly narrow breadth of experience, I found the acoustics of Hamer to be quite superb, and definitely one of the best that I’ve come across. The program was also impressive – world premier of Carl Vine’s The Enchanted Loom, followed by The Planets, by Holst.
Vine’s work offers five movements conceptualising the complex functions of the human brain, including awakening, belonging, creativity, euphoria and imagination [4]. The pieces orchestration gave Hamer’s acoustic response a workout, which provided an intimate and clear realisation when required. Dynamic, full orchestra passages were well supported and balanced with little muddiness, and the firing synapses of glockenspiel and piccolo carried through with ease.
Holst was performed comfortably as expected, taking us on the journey through the solar system. Fortissimo’s were immersive and surrounding, revealing a pleasant reverberation. A highlight was during Neptune, the Mystic, which features a hidden chorus of Sopranos and Altos, located unseen in the wings, and adding an eerie accompaniment before fading beautifully to silence*. It really was an aural treat, the disembodied vocal floating through the space, its source location not able to be pinpointed. It elicited many a head turn and appreciative murmur from the audience.
Usually, I leave the orchestral listening experience wanting more, with critiques around lack of intimacy and immersive-ness. I love the feeling of being within the sound, which is usually quite achievable with chamber performances in small rooms, but more elusive in large halls. I find the perceived sound field at typical “stall” level seating (close to, but below the level of the stage) to be adequate in intensity, but spatially poor, as instruments project slightly upwards and outwards resulting in sound energy passing overhead. Moving further from the stage is often an improvement spatially, but intensity can drop with separation distance. Raised balcony level seating tends to receive direct sound energy more “front on”, but again, the separation distance from the stage can leave you feeling disconnected from the performance.
Sitting elevated at Circle A35, approximately 25m (line of sight) from the stage, I was concerned I would be in the latter scenario; disconnected from the performance, and merely hearing the sound rather than being immersed in it. As it turns out, my fears were unfounded and I left very impressed and content. Away from the side walls, early reflections balanced very well with direct and reverberant sound, and intensity was excellent across the dynamic range. In combination with great sightlines, this seating position makes for an excellent Hamer experience and is highly recommended.
*Holst’s performance notes stipulate that the chorus is to be located “… in an adjoining room, the door of which is to be left open until the last bar of the piece, when it is to be slowly and silently closed.[5]” I’m not sure whether this was done for this performance, but if it was it was very effective.
Acoustic Elements
There are a number of notable acoustic considerations and treatments present in Hamer which contribute to its wonderful acoustic performance, many of which were added or tweaked in Marshall Day Acoustics 2012 renovation of the Hall.
Reflector
Perhaps the most apparent is the above stage reflector, which acts to reflect sound both back to the stage and towards the audience, reinforcing direct sound. The reflector can also be raised or lowered to different heights to suit the range of performance types that Hamer is host to, as demonstrated here.
Diffusing Facets
Side walls and ceiling are host to a large number of concrete facets, with acoustically quite large geometric profiles. Some Googling turned up a 2010 Marshall Day [3] Paper by Gulsrud, Exton, van der Harten and Kirkegaard [1], wherein these facets were a topic of investigation and ultimately modified as part of the renovations. It appears that the pre-renovation facets were less diffusing elements, and more sources of irregular specular reflections, resulting in a
harsh sound quality and unnatural apparent source directions at fortissimo dynamic levels. [1]
The solution was to add absorptive material to selected parts of the geometry, minimising the specularity of reflections from the facets, thereby decreasing our ears ability to localise sound as a reflection. At least from my listening position, the issue seems to have been largely solved, but thats not to say its more apparent in different locations.
Absorption
While there doesn’t seem to be any dedicated absorbing elements, this is par for the course for large venues for 2 reasons.
- They quickly fill people (and clothes), which are relatively effective absorptive surfaces,
- Seat cushioning is absorbing and plentiful, particularly in the high frequencies.
In fact, the combination of the above can often be overbearing and start to roll off the high frequencies if the hall designer is not careful. In Hamer, seating is about 50-50 absorptive/reflective (“sitting” surfaces are cushioned, while rear and bottom of seats are wood veneer and reflective), and floor coverings are a mix of absorptive/reflective striking a nice balance overall.
Balconies
Balconies can present difficult geometries, and the ability to create acoustic dead zones or strange reflections for the lower levels. In this case, the designer has opted for sweeping curved faces for the exposed edge of the parapet, mimicking polycylindrical diffuser design to minimise specular reflections from balcony geometry. Notice as well that the lateral curve is broken into offset sections, as opposed to a continuous curve to avoid focussing sound in the horizontal plane.
Other
A couple of elements at side stage piqued my interest (see below), so I wandered down at interval to get a closer look.
The voids within the downstage facets were revealed to be unused side wash and follow spot locations for lighting. The directional “venting” ports on the long horizontal facet are currently unknown, though I suspect its related to HVAC distribution (can’t imagine any use for Lampies). I plan to contact Marshall Day to see if they can shed any light.
EDIT: Confirmed to be ports for supplying ventilation to the stage. Oriented “so that the air projects into the room and drifts downwards to the stage without causing air currents that would create drafts for the musicians or turn the pages of their music” [6]
Bootlegged Reverb Times
As a bit of a challenge, I wanted to see if I could make any sort of measurement of reverb times during the performance. Typically the process involves exciting the space with either impulse, pink noise or sweep, processing the recorded signal and then averaging the result over a number of measurements at different positions. As a patron, my signal generation options were non-existent, and so was my ability to measure from multiple positions. What I did have going for me was Mars: The Bringer of War and its ending full of orchestral stabs, somewhat akin to an interrupted noise excitation, and a discreetly held iPhone. A bit of processing in MATLAB gives some indicative results.
Figure 1 shows the frequency content of the selected stab, as a waterfall plot.
In the initial stages where the orchestra is actively playing (approximately the first second), the frequency content is somewhat flat, albeit lacking below 100Hz and above 2kHz. The harmonic content is also apparent, particularly in the later stages of decay. It’s no pink noise, but workable.
From this excitation, we can calculate the energy decay curves in each single octave band, using them to estimate the RT20 and RT30 times.
The values and trends below 100 Hz are pretty rubbish and should be disregarded (due to lack of excitation energy), but in general the calculated reverberation times do seem reasonable. Comparing the values to those presented in the Marshall Day report [1] they actually hold up quite well.
So while I wouldn’t use them for any design or critical evaluation work, the bootlegged reverb time measurement method actually seems quite valid for indicative measurements.
Conclusion
I hope this has given a brief insight into the acoustic design of Hamer Hall. Almost every design choice, both seen and unseen will affect the acoustic performance of a hall in some way, and its a constant battle between physical constraints, budget and aesthetic. Though I did not catch any performances at Hamer pre 2012, the general consensus is the renovations have improved the acoustics significantly, and I’m inclined to agree. I’m looking forward to seeing many more shows here, hopefully a variety of genres and artists.
References
[4] Vine, C. Symphony No. 8, The Enchanted Loom (Program Notes).
[5] “The Planets” (full orchestral score): Goodwin & Tabb, Ltd., London, 1921
[6] https://twitter.com/MARSHALL_DAY/status/1045116544139714560
Credit to SouthDogImages for photo editing and colour correction.
