Lossless audio compression for project work and archive – what do you use and why?

I’ve been using lossless audio compression as a matter of course in my audio workflow for a while, and not just for end-distribution.  Services like Bandcamp and Soundcloud support uploading in FLAC format, and many clients happily accept ALAC (Apple Lossless) or FLAC in place of traditional uncompressed WAV or AIFF formats.

As for long-term storage and archiving, I’ve switched to FLAC for my projects, and have back-converted most of my catalogue.  But why FLAC?


  • The reduction in network bandwidth and storage requirements is always nice.
  • It brings the possibility of checking the project audio files for errors via the FLAC checkum (applied at the time of creation) against how the file decompresses in present-day.
    • This can show up problems with “bit-rot” on disk storage that would otherwise remain hidden.  It’s a useful alternative to deploying ZFS-based file systems and keeps storage and network kit at an affordable “prosumer” level while such technologies mature a little longer, and hopefully come down in cost too.
    • If I find a problem file? Fine – restore from a good backup.  But that does rely of course on having good backups, and the corruption not being carried into those!
  • It’s an established format that many, many software applications can read, across a wide variety of operating systems – and given the number of websites springing up offering “audiophile” digital transfers of consumer audio material based upon the format, I have good confidence that software to read and write to the format will continue to be developed for some years ahead.  And if not, it’s still easy enough to batch-convert files to whatever format replaces it.

Cons (none unique to FLAC, I notice):

  • Reaper is my DAW of choice, and exporting large projects out to FLAC is time-consuming as it still doesn’t multithread FLAC exports for projects.
  • While Reaper *does* support (in version 5.111, at last check) recording directly to FLAC and other formats, recording to anything other than WAV or AIFF on my systems has consistently thrown up audible glitches in the recorded material. With some sample-accurate editing these can be fixed, but still not acceptable.
    • What I do therefore is to record to WAV/AIFF first, then save the project to FLAC before any significant mix down happens.
  • Not every DAW supports FLAC natively, or at all.  But then, for me this is a moot point – not every DAW can read project files from every other DAW, so this is just a part of that wider picture.  You pick your tool for the job and deal with the consequences.
  • Conversion takes time, especially offline for large projects.

So  – that’s a quick brain-dump of how I’m working with this stuff and why. I’ve missed steps and I’m sure others will be quick to pick holes in it.

I suppose my question to anyone else reading this with sufficient interest is… What is everyone else doing? What file format would you pick, and why?


Preview: “O Holy Night” – performed by ASO and Constantine Andronikou

So here is a quick “faders-up” preview of “O Holy Night”, as performed at All Souls Church on 12th December at Christmas Praise – what a stunning event that was!

Credits as follows:

  • Composer:  Adolph Adam
  • Singer: Constantine Andronikou
  • Orchestra: All Souls Orchestra
  • Conductor: Dr Noel Tredinnick


  1. Because there’s such a huge dynamic swing between loudest and quietest parts of the piece (some 20->40dB depending which metering standard one uses), I’ve approximated what I *would* be doing with faders by using compressors.  The result isn’t yet “pretty” but it is functional – at least enough until it’s decided whether further work will be done!
  2. Though I helped provide the technical links between live and recording “worlds” for this event, I’m not actually involved in producing the radio mix. 🙂


Pilgrim’s Pod Radio Hour – Episode 3

UPDATE (26/2/2014):

This is the edited version, to keep the show length under an hour, and to tidy up some slower-moving passages.


Another episode was recorded on Friday 7th February.  A slightly different feel to this one – with more spoken content. Featuring Liz Jadav and Phil Gallagher.

Technical notes

This time, the live-stream was sourced from the software mix that created this edited recording.  I’ve fixed a mistake where I ran out of hands to sort the live-stream mix during the intro, and we re-recorded a song with Paul after he’d choked on some water just before his song!  Aside from those issues, the stream levels were much more easily managed this way, and mixing the recording live with the usual processing in-place also made this edit much quicker to produce!

Also new to us was a Superlux S502 ORTF mic (select “English” from the top-right of the linked page), used for room ambience and audience.  Compared with the AKG 451’s we were using, rigging was much simpler, and the resulting sound was slightly more consistent.  I’m really pleased with this mic in this and some other applications; subject for another post I’m sure!

Pilgrim’s Pod Radio Hour, Episode 2 – Christmas Special featuring @miriamjones

Well, here’s the second episode of the Pilgrim’s Pod Radio Hour, with our host Will Mackerras, Paul Enns leading the band, and our special guest Miriam Jones!

I’ll possibly expand on this later, but we had a lot of fun making the show, so I hope you enjoy listening to it!

“Podcast mix” – The Pilgrim’s Pod Radio Hour – Pilot Episode!

Last Friday, a few of us gathered in in London’s Fitzrovia suburb to put on the first Pilgrim’s Pod Radio Hour – a pilot of a show that we hope to continue on a monthly basis.  As their technician, I can say I had an absolute blast making this all work for them.  The idea was that we’d have a live audience in the room, we’d stream it live online, and then release a podcast recording.  The latter is still in progress, but I have permission to release a copy of it here as a showcase, and as an additional plug for the show! 🙂

More details about the show itself are available at its blog:  The Pilgrim’s Pod Radio Hour

Given the technology used, and the fact that this was a first-time run for both the technology and the format of the show, I’m really pleased with how it came out – hence the post here!

A rough tech-spec can be summarised as follows:

  • Rode Procaster microphones for Will and Sarah (@Sarahlynne42)
  • Shure SM58 for Paul Enns vocal
  • Baggs Venue Active pre-amp/DI for Paul Enns acoustic guitar (Paul and I have worked together for a couple of years, and we both love this on his various guitars!)
  • Shure SM57 for snare drum
  • EMO E520 passive DI’s for keys
  • DI-out from amplifier for acoustic bass guitar
  • AKG C451’s for ambience, acoustic guitar, fiddle, mandolin
  • Pre-show music playback from Asus netbook, plugged directly in to sound desk stereo input strip, running Multiplay for Windows
  • Mixed on Soundcraft Spirit 8 32-channel (analogue) console – not keen on the pre-amps, and headroom leaves something to be desired, but it’s more than workable!
  • 8 groups (Will, Sarah, Ambience L/R, Paul vox, Paul Guitar, Band L/R) used for:
    • Live room mix (via matrices for FOH and simple foldback, each derived from mixer sub-groups)
    • Live streaming mix (via Main L/R, derived from groups)
    • Group outputs captured for multitrack recording
  • 2007 MacBook Pro 15″ computer for live streaming and recording
  • Presonus Firestudio Project firewire audio interface used to capture the 8 mix groups.
  • Mixlr.com app used for live streaming to http://mixlr.com/pilgrimspod

The “podcast mix” heard here was recorded from the groups, and some  limited editing and processing was carried out in Reaper using its built-in plugins.  The only real “cheat” was the free flux ST-Tool, used to expand the stereo image apparent on the ambience mics; necessary because I wasn’t able to use my preferred spaced-pair ORTF mic setup due to the layout logistics of the venue.  Maybe next time I’ll work out a way to fly a pair on sky-hooks, or something…

As for the show itself – we’re taking a break through the Autumn to gather our thoughts and take our pre-planned holidays.  We’ll be back in December with a new episode – the actual date and time will be announced later.

Queen and George Michael – “Somebody to Love”

Pic: “iPod headphones: hangin’ out” - by el patojo, courtesy of Flickr.
Pic: “iPod headphones: hangin’ out” - by el patojo, courtesy of Flickr.

While sat on the train this morning I found myself listening to this track when it came up on LastFM. I’ve been a big fan of this rendition ever since it was first played live in 1992 at the Freddie Mercury tribute concert. I love the energy and the ‘live’ feel it has – and since the song in its original format was already a childhood favourite the whole package made a very lasting impression.  The experience of listening to this broadcast live was one of the many experiences that got me interested in all things sound-related.

Listening to the song again as an adult, one could bring up all kinds of conclusions about how the writer was feeling about sacrificing a lovelife for life in the rock ‘n’ roll circus, but i’ll leave that commentary either for another time or another (more expert) person to deal with.

What really got my attention this morning was just how patchy a production this recording seems. See, I’m living in a spoiled age where there are many technically great recordings to listen to, from several generations. Yet occasionally, a truly great song bursts onto the scene with huge energy, and the fact that anything was captured to tape at all is nothing short of a miracle.

This for me is one of those songs. The event, the musicians, the song and the soundstage are huge. Some really serious compromises had to be made to commit this song to tape. Yet it’s interesting to hear retropectively where the engineering and production placed the focus of attention. Was it the crowd? Nope. The singer? Nope. Was it… the guitars? Nah-ah. What about the piano or bass? Those neither.

The only instruments at dead-centre of the mix and the soundstage are… The hi-hat and snare drum. These completely dominate the track in a way I’ve never heard before in commercially successful releases. It’s just insane. Everything and everyone else sound like they were playing in a separate room, nay, stadium. And these two disembodied percussion instruments are presented so close to my face that I’m flinching with every beat, fearing I’ll be struck by a flying drumstick.

This made me wonder what the decision process must have been to get there… “Uh, Frank, we’ve run out of channels on the tape. What do we keep? The singer? The bass?”

“nah, it’s alright Jez.  They’ll come through from the stereo broadcast. Let’s give the drums a little more impact. What we really need is more fizz.”

“what? But won’t that sound wrong somehow?”

“maybe, but it’ll be a trademark…”

What the…??? Now don’t get me wrong here, Roger Taylor is a great drummer, and to my ear his HiHat technique did become something of a trademark of his during the 1980’s. But does it really need to take over the song to the point of masking the singers?

Sorry – I didn’t mean to criticise. But i still stand by the fact that i’d choose to mix it differently, which I think would transform the dynamic of the whole song. If i could mix from the (presumed) multitracks i’d also see if I couldn’t make some more out of the crowd and assembled on-stage chorus.

Am I being unfair?