Swirlies, garblage and undersampling

[Tom Wells]

OK, I'm not going to say it sounds like ----.  I'm going to say that if you want to stream audio, you should figure out how much
audio upper end your source has,  how much resolution your stream has, and then PRELIMIT the audio passband so that you don't try to make sine waves out of huge stairsteps.  At 56K and up, it is possible on the decoding end to use a dynamic-passband filter like National Semiconductor's DNR (dynamic noise reduction) to smooth the result and give an FM-like output.
Below this speed, if you are streaming anything that contains more high frequency response than old-fashioned Plain Old Telephone Service
(POTS) then you should high frequency limit BEFORE the encoding.
When the few remaining scraps of the higher frequencies are still present, but there's not enough to make a sine wave out of,
it is so distracting as to make the end result annoying, unlistenable, sickening, etc.
Our ears and brain KNOW that nothing ever sounds like this, and it is disconcerting to hear a recording where you KNOW how it should sound, but it doesn't.  Plain human voices are still going to be trouble, as the upper harmonics suffer first, but at least music CAN sound somewhat acceptable if this is done.  Example- CD data rate of 44.1 khz can only resolve 22.05khz audio so high limit at 20 khz.
Most streams I'm hearing ought to be chopping things off at 5 khz audio to sound clean.
Instead, they try to sample the "whole thing" and the audio jaggies are way too distracting.

[Josh C.]

How about this: process the audio to your taste, then do a bandpass filter to remove the upper frequencies and adjust your processing to compensate?  I've been experimenting with that for some time, and it sounds great to me.

Of course, you could just do everyone a favor and go MP3pro so you sound clear no matter what bandwidth at which you stream.

[Tom Wells]

I'm  don't stream, at least can't imagine yet I would ever.  as I prefer all modes analog, accept CDs as OK, and listen to audio from various sources online.

I am offering helpful suggestions to those streaming who can only afford so much bandwidth, or are currently encoding stuff.
There are online streamers i might like to be able to enjoy, but the result is far worse than is worth the effort.
Shortwave radio with deep fades might be approximately as annoying.

Clipping off the high in a static manner sounds awful.  Any processor with a dynamically-variable upper limit set to cut about half the "brightness" out of the audio sampled will sound far better for ALL listeners, regardless their players.

I wish I could recommend KAB processing equipment, I can't afford it but all looks good.
I get by with a unit once sold (accidently, probably) by radio shack in the mid 80's as a video sound processor.
It has 3 inputs, and switchable and variable DNR hiss/noise real time active processor that was marvelously ignored by the public
yet was about the last smart thing GM ever did in a car radio.
 Google DNR National Semiconductor, something oughta come up.  It's great.

Anyway, limiting the upper end when it can't be supported will sound better.
At least for the streams that are 96 or lower.