[App_rpt-users] USB Sucks Yay! The Sequel!

Bryan D. Boyle bdboyle at bdboyle.com
Thu Jan 12 14:13:07 EST 2012


Yeah, USB sucks.  But, then, a little perspective....

At the base case, what are our expectations?  Full 5.1 surround sound, 
broadcast quality?  For a communications-channel radio?

Don't think so.  It's a waste.

I'm thinking that, and this is based on my experience only, so, if yours 
is different, you'll have a different take on it...

The URI does what it does well.  It's a $79.00 USD audio-to-USB adapter. 
  It is unique in what it does.  And it does it a LOT better than 
anything else I've found out there at that price point.  For $79.00, an 
old computer, and some time, you get a full feature, 
internet-connectable, network-able, totally configurable radio 
controller with more features than you'll ever use.  Try doing that with 
an SCOM or Arcom hardware solution for the same price.

For instance...broadcasters are using, solely as backups in most cases, 
audio to IP encoder/decoder sets from a company called Barix.  It takes 
an audio stream, turns it into IP packets, and broadcasts it out.  Guess 
what?  Costs around $450 for the encoder (with wall wart) and $250 for 
the decoder (ditto).  50-15K stereo with a 100MB RJ45 on the back to 
plug into the network.

That's all it does.  No useable DSP to derive control signals, no 
hardware controls, no user-programmable I/O.  Audio in...IP out...IP 
in...audio out.

Now, on the other side, you have the Universal Serial Bus.  Not the 
Universal Audio Bus.  It's a one-size fits-all solution.  You can plug 
in a URI, Logitek Webcam, HP Printer, your keyboard, mouse, and a missle 
launcher toy from GeekToys, and they'll all be recognized, and if you 
have the app to drive it...will all coexist and work off the same bus. 
That it's not optimized for any one protocol means that it works 
(sometimes poorly) for all of them.  It's one of the biggest compromise 
technologies in the PC world.

So, do you get the occasional pop or crackle or ?  Sure.  Is it the 
URI's fault or the back end itself?  And if it is the back end (which it 
is more often than not...), what is the cost, in folding green (or 
whatever the prevalent color of your local currency is) to make the next 
step UP in quality for what is, at the transmission point, a 
bandwidth-limited, distance limited, purpose-limited communications system?

The human mind can work with degraded video transmission frame rates 
because the visual engine, so to speak, can fill in the transition 
between receipt of one image (persistence of vision) to the next.  Not 
so with audio; our hearing is based on linear (in terms of time slices) 
response and except for the occasional case of your ears ringing, has to 
hear a continuous stream in order to made sense of the entire communication.

That's why we can watch a 15FPS video and still think it's something 
(which is 50% of the normal US frame video frame rate and 9 FPS less 
than movie projection) but, if you interrupt an audio stream for 50% of 
the time...it's unintelligible.

So...is the delta to get to what you consider a perfect system worth it? 
  If you have the funds, the processing power, and want that broadcast 
quality (you ought to listen sometimes to the 160 band and all the old 
pharts running cast-off broadcast transmitters...AM..) 99.9999% 
reliability?  Go for it.  But that does not mean that the technology is 
useless; in fact, for both price and ability to implement, it may well 
be more economical and efficient to accept the occasional pop and 
whistle if the cost and ease of implementation warrants it.

</soapbox>

-- 
Bryan
In this world, you must be oh so smart or oh so pleasant.
Well, for years I was smart. I recommend pleasant.
You may quote me.

Sent from my MacBook Pro.



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