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Old 23rd Nov 2008, 18:44
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seacue
 
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You might complain about audio quality of SiriusXM. Reportedly some music channels run only 24 kilobits per second. But that's the 40s channel and presumably in mono. The classical channels are assigned many more bits. XM uses AAC+, which is a good compression scheme for low bit rates. The Sirius compression scheme is said to be not as good.

That said, I have been an XM subscriber since only a couple of months after they started in 2001 and enjoy the 40s channel (which covers much 1930s music as well). My deteriorating hearing means that I don't notice the low bit rate.

Sirius and XM are at about 2300 MHz, and have numerous terrestrial repeaters to cover some bad spots.

US AM and FM broadcasters have "HD Radio", "in-band, on-channel" digital broadcasting. Actually it slops over to the channels adjacent to the station's main signal. This creates destructive interference which is so bad that very few AM station broadcast digital at night. FM HD isn't as destructive to "neighbors". The bit rate of HD for AM stations is less than 32 kbps. The rate for HD on FM stations is 96 kbps, but many subdivide into into a number of programme streams. The compression scheme isn't quite as good as AAC+. FM HD with all 96 kbps assigned to one programme stream isn't bad., probably better than analog FM when there is considerable multipath.

In any case, very VERY few HD AM/FM receivers have been sold.

Sony makes an HD AM/FM tuner which is said to be about the best analog FM radio ever be offered to mass market (and at $99). The HD feature can be disabled by snipping one wire. See the excellent review by K6STI.
Sony XDR-F1HD
It tunes in 100 kHz steps on FM, so might be useful outside the USA. Unfortunately it only tunes in 10 kHz steps on AM.

(Edited to improve format, detail.)

Last edited by seacue; 24th Nov 2008 at 01:22.
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