One of the more curious learnings I’ve repeatedly had over the decades is that audio and video quality isn’t terribly important to people. Some jumps have been important, but at some point quality seems to be “good enough” and people become interested in other metrics like price, mobility, convenience and selection.
We did a lot of work on audio compression and there was a drive to make our codec (AAC) the best of its class. This involved a large amount of human testing and the reference music was mostly compact disc class. Higher qualities existed, but it was felt compressed music to CD like quality was necessary.
We did it. By 2000 AAC was recognized as the best of its breed and it was statistically undetectable to most listeners at 128 kilobits per second.1 A CD is 1440 kbps, so this shrinks the data file for a music track to about 9% of its original size - really useful if your network connection isn’t terribly fast.
Audiophiles had been hoping one of several standards would take off by about that time taking us beyond CD quality, but it never really happened. Internet delivered music and the iPod fundamentally changed how we listened to music. A few years ago I came across an article that pointed out the aftermarket for iPod accessories was larger than the entire market for stereo equipment. Good enough sound quality in our pockets and a large and easy to use library was all we needed - onventional HiFi was dying and some would say it is dead.2
The little white earbuds you see everywhere are not exactly high quality. For $40 or $50 you can dramatically improve your listening experience and for $150 or so the quality can be fantastic. But almost no one does it. The quality issue just doesn’t impact most of us.
There are other directions music quality could do - trying to create the sound field - the audio experience - of a concert. But there is this little problem - outside of multichannel sound for television, no one is spending money on audio equipment and very few people spend serious money on good audio equipment for their televisions.
It just doesn’t matter.
A few years ago some of us revisited the issue of speech quality on telephones. The frequency range of a normal telephone is small compared with normal human hearing and voices, particularly female voices, are altered. Mobile phones introduce even more issues with low quality audio compression. The notion was that expanding the frequency range from about 3 kHz to 7 kHz would make a big difference that people might pay buy. We did some careful studies on 3 vs 7 vs 20 and came to the conclusion that it isn’t a big deal for most people. In fact people under 30 had a slight bias to the lower quality sound.
I speculate that for music or video there is a point at which the underlying performance is more important. If we don’t reach that point the performance is merely wallpaper and we don’t pay a lot of attention to it. As we cross some threshold what is being the performance becomes so engrossing that inferior reproduction isn’t a huge issue to most of us. I’ve seen this repeated over and over ... In an earlier post I noted on an epiphanal moment I had:
A good example is that the enjoyment of music often is decoupled with the quality of reproduction. I was in a classic restored Mustang near Cleveland with the head recording engineer from Telarc Records and a seriously good musician from the Oberlin Conservatory. We were talking about where music reproduction might go with sound field reconstruction and dramatically more information than CDs could provide when a favorite Beatles tune came up on the 8 track (gasp! - it was an authentically restored Mustang). The volume came up and the two of them were soon singing along to the music in pure delight. There is something transcendent about the music - even with the awful reproduction in that noisy environment. This taught me home stereos might die if we could only give people good enough music that was always with them. Portable music players with cheap headphones would be good enough.
I think live performances are still very important - there is a communication between the performers and the audience and the overall sound field seems to make a difference. The one way music and video we listen to at home or on the go is a different animal and needs to be considered separately.
This notion of good enough quality is important. You have to consider the entire user experience and not just some component like audio quality as defined by some engineering metrics that are measured with the listener out of the loop.
It is something to watch for in many other industries. Most people could care less, and don’t even know what gigahertz, gigabytes and other terms used to sell Wintel based PCs mean. The same for horsepower and torque. They are used as sales tools and people might think larger is better, but there is only a vague coupling to the final experience in most cases. Even non-technical enthusiasts have trouble with the definitions.
Perhaps industries where differentiations are made based on technical terms that are not understood by the customer based are a good first order cut as those where disruption is possible.
Video and theater experiences are another rich and interesting area. A lot of money is being bet that 3D will cause people to upgrade home TVs as well as go to movies, but there are some good arguments that won't happen. There are other things that are probably more important in the theater and I tend to doubt the 3D revolution - at least as something that is a sustainable differentiator that will cause people will pay higher ticket prices.
In the meantime I love going to live performances! In the meantime don't bet on quality metrics unless you understand the complete user experience.
1 In fact if you increase the rate to 160 kbps statistically no one can tell the difference on normal music. The guy who was really obsessed with tuning the codec went to Apple and their version of AAC has made great improvements over the years.
We found that some training is necessary to listen closely enough to music to detect artifacts. It turns out that hearing ability decreases and anyone over about 35 is useless no matter how good their training. Audiophiles tend to be males over 40 (and more often over 50) who spend tens of thousands on equipment.
2 Apple recently released their Apple Lossless Codec (ALAC) to open source. Lossless codecs like Apple's and FLAC tend to offer compressions around three to one. The file that is compressed can be turned into a file idential to the original so they are "perfect". A few audiophiles use them and some companies even offer music, but this is a very small business.
ALAC has some advantages over the other lossless codecs as it works with iTunes and iPods. It can also work with music recorded at much higher than CD quality. Now that it is an open standard perhaps it will gain some popularity among the enthusiast set. The fact that Apple is releasing it shows they don't see any commercial value.
3 At home I still use my 15 year old amplifier and once fine speakers to connect with my MacBook or iPhone or iPad wirelessly. My 20,000 or so tracks worth of music is completely portable and distributed where I fancy on listening at the moment.
But I see no need to upgrade the system and the CDs just sit - I converted them (at 256 kbps AAC) a long time ago...