Source : Globe & Mail

The following letter was received in response to Jack Kapica's column The Radio War:

Dear Editor:

I read with great interest the account of Jack Kapica's tryouts of Sirius and XM satellite radio, and his analysis of the coming battle on content, national and local.

However I was sorry to see him passing on uncritically the industry's self-serving myth that their broadcasts are "CD quality" (they used to say "near-CD quality," but that was too long). Both companies use brutal codecs to compress their signals. Sirius uses PAC, which even its designer (iBiquity) considers obsolete, having moved on to the HDC codec. XM uses AAC+, a variant on the codec used by the iTunes store. The word "codec" (compressor-decompressor) is a cruel joke, because no decompression actually takes place. The majority of the signal information (from 80 per cent to 92 per cent, depending on the channel) is discarded.

Is this reconstructed music better than FM? Well, all digital radio is inherently noise-free, since you either receive it or you don't (and as you discovered sometimes you don't). And certainly commercial FM has been deteriorating, with a great deal of compression and signal processing intended to make stations sound louder, not better.

What's more, pop music stations now receive most new music releases on-line rather than in CD form, and those releases are in (compressed) MP3 format.

For a demonstration of FM at its best, listen to a live concert on CBC Radio Two. That sort of quality, actually superior to CD, is accessible to any station that wants it.

Around here, our slogan is "jst sy no to lssy cmpresn."

Gerard Rejskind, Ultra High Fidelity Magazine, www.uhfmag.com

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