Monthly Archives: October 2012

Remastering electroacoustic music

I’ve been working on a project preparing archival recordings for broadcast. This is part of the Resound project, a collaboration between Radio NZ Concert and SOUNZ which aims to make Radio NZ Concert’s New Zealand Composers Archive available—selected works are being broadcast in Sound Lounge between now and the end of the year, and most of the archive is available online, as media on demand at the SOUNZ website. I don’t think there’s a direct entrance there—the audio files are embedded on each individual piece’s page—although a search for ‘Resound’ produces a lot of results…

From the point of view of remastering, the pieces for broadcast generally fall into two categories. There are older works, which have uneven audio levels, and tape hiss, and sometimes tape degradation—some of these need significant amounts of work. The more recent recordings generally only need level adjustments—many of them are mastered as if for CD, using the full dynamic range—what I’m aiming for are files that can be dropped into a compiled programme without any further treatment, so the levels need to be inside a range that won’t freak out the transmitters.

Most of the time, this is straightforward—it’s the same balancing act we do in making feature programmes, dealing with the technical limits, while not doing too much damage to the music. But for a few pieces this balance is problematic. It’s most obvious in electroacoustic music—in an instrumental piece there’s a perceptual separation between the recording and the music, whereas in electroacoustic music those two things are (usually) much more closely intertwined. So there’s a stronger sense that, in changing things like the balance and the dynamic range, there’s a risk of making musical changes—a risk of going beyond making the piece come across more clearly on radio, into altering the work itself.

Of course there are also instrumental pieces that veer into this territory, especially those that use very quiet sounds. Music that’s very quiet all the time is particularly difficult on the radio.

But the example that really raised these questions was a piece of my own—Mists and Voices, from 1999.

The piece was designed to be presented in a room full of speakers. On the radio, its dynamic range is problematic. The loud stuff is easy enough to control; the real problem is that a lot of the piece sits near the threshold of audibility. So the difficulty is as much aesthetic as technical—simply turning up the quiet bits changes the music. In particular, if the dynamic range is narrowed too far, the distinctions between foreground and background are removed. There’s a lot of detail in the quietest parts, but if it’s raised to the point where it’s clearly audible, then it assumes an importance it wasn’t meant to have, and changes the balance of the various materials that make up the piece. But the original master couldn’t play on air—on most people’s radios, it would be mostly silent, and that’s not the piece either.

As far as I can remember (1999 was a while ago now), I intended for the quietest parts to be ambiguous—for the listener to be uncertain whether the sounds were in the music or in the room. So it’s already risky in the concert hall; the question here is how to replicate that in a way that will work within the technical constraints of a radio broadcast. At the time I made it, I had one kind of presentation in mind, and there’s one version of the piece that’s made for that context. Now, however, I’m coming to the view that there can be multiple versions for different listening conditions, and I’m still working out whether different contexts need different mixes. (Of course, it depends on the piece—this particular piece seems to be especially sensitive to these questions.)

The version above is closer to the original than the broadcast version, but the dynamics are tweaked a little, so it should be audible on computer speakers. I’ll find out whether the radio version works when it’s broadcast on 16 October.