Wednesday, May 02, 2018

The Quality Of Audio Is Really Strained...


I'm a musician whose school holiday job was in a recording studio. I care about audio.

So, my recent experience with Amazon is worrying. First of all my Fire stick stopped streaming audio and just delivered absolute white noise. I've stopped using it now in favour of a Roku stick.

Then, watching the Grand Tour on my LG TV with a Roth sound bar the background phasing was so bad I stopped watching. Then this started to happen on other Amazone programmes.

In my den, using totally different kit (Sony/Sonos), the effect was even worse. The excellent US detective series Bosch was unviewable with a washing machine going on in the background.

At a third rig at my Welsh home  (Samsung TV and 3.1 LG 3.1 sound bar) the phasing wasn't present, but there was bad audio lag, meaning I had to restart my kit every thirty minutes or so. Netflix and iPlayer were fine.

Then a friend, who works for a major broadcast company, called to say that they had lost sync on a live event, both live and after uploading to YouTube and Facebook.

There is one common denominator in all of this - Elemental, the mercurial encoding company acquired by Amazon. At an event this week hosted by TV Everywhere their products were derided by some of the industry's leading encoding experts.

Video/audio encoding is an art where AI should be in its element (so to speak..). But, to date, it is not. It demands humans to look at the thousands of variables and optimise them for any particular video (or, ideally, a scene within a video). The outcome is always a compromise.

It all reminds me of when we figured out how to strip the audio from AVI and place it in the header so that both MOVs and AVIs would play with just one file on CD-ROMs. One day a client reported an audio track playing at double speed. It turned out that AVIs used the clock on the sound card for timing and that the driver was out of date. This stuff isn't easy.

There is one open source encoder that, to my knowledge, every commercial solution cuckoos off FFMPEG (and related products such as FFPROBE) so this is not even a commercial problem.

I could delve deeper into this very specialised world, but to me, it seems that Elemental has optimised its encodes for Dolby surround environments, whereas almost no one actually uses this set up. On anything not Dolby surround it sounds dreadful. Moreover, the lag issue seems to be a separate problem.

In reality, I am a happy customer of Amazon Prime and I do hope they sort this out quickly.