Composer Stephen Barton Returns for Spatial Audio Experiments

Last month, film and video game composer, Stephen Barton, returned to Abbey Road's Studio One for some experimental sessions with our own Mirek Stiles. Pushing things beyond their comfort zones, and in the process achieving some spectacular results, Mirek recaps the day below.
 

The Session:

Spatial Audio was the name of the game (not literally). As with our first set of experimental sessions last year we had a full arsenal of spatial audio arrays at our disposal including the Core Sound Octa 2nd Order microphone, Sennheiser Ambeo Cube (Hired from Studiocare, Liverpool), Hamasaki Cube and an Equal Segment Microphone Array.

All this came with a hefty 42 channels of additional microphone inputs needed for the session, hefty when considering this channel count was in addition to recording engineer Alan Meyerson’s traditional orchestral recording set up. The session came to about 128 inputs in total, feeding into Pro Tools.

For fear of clashing with Alan's setup too much, Stephen and I opted to locate a separate mic preamp system that we could feed the extra microphones directly into Pro Tools from the studio floor via Madi. After a little asking around, Dan Cole from Abbey Road’s technical team put me in touch with Jan Lykke from NTP Technology who developed the DAD AX32. This thing is stunning, 48 channels of high-quality microphone preamps that convert directly to Madi and can be remote controlled from the control room via a laptop. It was exactly what we were looking for. Jan very kindly loaned us a unit to experiment with and the AX32 totally nailed it.

 
 
Microphone wise we tried a few new tricks. Both Stephen and I had experimented with all the arrays in the past. Last time the orchestra was a little smaller and the room was laid out portrait style. This time the orchestra was larger (especially in the string sections) so we laid the band out landscape giving more width, and hence more space for the musicians, otherwise it can get a little tight with the risk of someones bow ending up in another player's eye.

The only problem from a microphone point of view was this meant we didn’t have much room behind the conductor to place the spatial microphone arrays (see image above). At best we could just about squeeze the Hamasaki Cube in between the conductor podium and studio wall, proper first world problems to solve. This time we also went for a 2m x 2m cube which is more to the original spec, last year we used 1m x 1m Hamasaki cube for some reason that can’t quite recall. So, we had to get a little more creative with how to use the space available to us.

Alan suggested putting the front row of the Ambeo Cube in between the 1st and 2nd violins on the left and violas and Cellos on the right, with the centre microphone place in front of the conductor podium. The back row of the Ambeo cube was the left and right. In a nutshell it meant the front row was actual in the orchestra and the back row just in front of the orchestra. We then took this concept further and placed the ESMA at the back of the strings in front of the woodwinds (see image below). The Octa microphone was placed just under the Centre microphone on the traditional Decca Tree array over the conductor’s head. I think this is a great example of being presented with a challenge and coming up with a solution that’s better and more creative than if the challenge wasn’t there in the first place.

During the session planning I was concerned when told we will be doing the session landscape – how would we fit all the microphones in position I though? You’re forced to look at a situation in a different light and as per usual you’re pleasantly surprised by the outcome.
 
 

Post Production:

The priority on a session with these sorts of arrays (particularly when you are literally tagging onto a primary set up which you can’t get in the way of) is ensuring all the channels are working, going to the right holes and labelled correctly. Monitoring all the Spatial Audio options in any meaningful way on session just isn’t practical. A few days later, once I had the Pro Tools session on my laptop in the relative calmness of the office, I could get to work on actually auditioning the various microphone options.

The Octa microphone needed to be converted from A format to B format via VVOctoEncode plugin, I then bumped it up from 2nd Order to 3rd Order via the Blue Ripple Upsampler plugin. For the Ambeo Cube the usual Ambeo Pattern plugin was inserted over each set MKH800 microphone channels, this enables you to select a polar patter for each microphone. In this instance I really loved the Omni pattern. For the encoding and panning of the Ambeo, Hamasaki and ESMA I used the Blue Ripple 03A panner and decoded everything to headphones via the Blue Ripple 03A to Stereo plugin. It can take quite a while (best part of a half day) to actually get all of the internal bussing, converting, plugins, panning and routing set up in this fashion – just one of the current pitfalls with Spatial Audio.
 
 

Conclusion:

Well I’m happy to say all the microphone options sounded pretty amazing in their own unique ways. The Hamasaki gives beautiful diffused sound, like a Spatial Audio reverb return. In the past we have used Neumann U87's for the Hamasaki Cube which always sounded a little “honky” in the mid-range to my ears, so this time we tried the AKG 414 which for this application provided a smoother room tone. The Octa microphone gives an outrageously precise sense of location, the spatial accuracy of that microphone is quite stunning. The Ambeo Cube just sounded huge, it was a nice effect to have the front row of the array “in the orchestra”, the sense of immersion was greatly improved with an increased sense of depth than just having the array plonked in front the orchestra. The trusty ESMA (I do like a good ESMA) gave a lovely sense of gluing the front and back of the orchestra together, a very useful trick for adding additional focus to the overall immersive soundscape.

All in all, it was an impressive selection of options that each had a unique flavour to offer. Once I started experimenting with blending the arrays together the overall effect was lush, focused and above all fun – by that I mean taking something you’re familiar with and hearing it in a new and exciting way. I think the only thing I would change is microphone choice for the ESMA. I used Neumann KM184 which don’t have a huge amount of low end, so might try something like the Schoeps MK21’s next time. Also, when speaking with Dr Hyunkook Lee recently at AES convention York University he suggested adding a layer of lower microphones on the ESMA to pick up floor reflections (nice idea!) – I’m going to try that next time, it would be rude not too.