Maybe audio streaming on the internet is slightly off topic for this site, I haven't noticed much said about it. But on the other hand many Part15ers have radio streams and sometimes they're used as signal paths between studios and transmitters, or as "third" outlets, after AM & FM.
Free mp3 streaming tools seem to have scarce support elsewhere, so I'll at least open a discussion to see how far it goes.
Shoutcast provides free software that works very reliably, but the lowest streaming rate is 24kbps, 22,050kHz. Yet many streamers can be seen by scrolling Shoutcast who have lower rates, i.e., 16kbps at either 11,025kHz or 16kHz, the advantage of which is being better receivable on dialup accounts and slow computers.
The various free servers that provide 16kbps have all failed to function properly, those being Edcast and Jetcast, discovered as plugins at Winamp.com There is no support for those so I'm coming to Part15.us where everyone has been so super helpful with so many questions.
How can the 16kbps mp3 rate be achieved?
Hi Carl,
"How can the 16kbps mp3 rate be achieved?"
Chat with primcast.com. However, I've heard stuff at that bit rate, and frankly even voice sounds bad ... forget music altogether, it'll be unlistenable.
Here's a sample of the intro I did for a Halloween show comprised of a few OTR horror shows from the '50's:
http://www.pixelbird.clearwire.net/Library/AudioLib/Halloween.mp3
It wasn't all that great as it was, but I wouldn't try that at the bit rates you suggest, it would've lost too much.
The audio compression of mp3 coupled with a 16khz bit rate would make the audio quality very fatiguing to the listener. Listener fatigue is the number one reason people don't stick around to listen long term to audio media.
My suggestion would be to investigate the AAC+ codec used by many internet broadcasters who don't have reliable high speed static DNS feeds. Reliable high quality audio can be broadcast with as little as 38 kbps. And some Shoutcast stations provide AAC+ or AAC-HE feeds.
kk7cw brings up a good point in that it's a good idea to look at the whole digital audio chain when considering streaming. The best source files are created especially for the streaming project, exactly mirroring the stream metrics. PC Sound cards are notoriously nasty when using what ever you find in the box. Different encoding applications (Oddcast, Shoutcast, WinMedia ENC, etc.) have different strengths and weaknesses, too.
There can also be problems at the receiving end. I run a little police scanner blog for my end of the Lake Washington basin (south Seattle and the south King County communities) and encode and stream my own feed, too, at:
southkingcountyscanner.blogspot.com
I initially tried 16 kbps with WinMedia Encoder 9 on WinXP but my listeners complained of buffering and drop outs. Those problems went away at 20 kbps.