"Codifus" wrote in message
...
| datanet wrote:
| Hmm, good reply, hel. Only your forgot 16 bits: That's the
| width of the data stream, meaning 16 bits at a time is
| transmitted in the data stream. Or, ultra-simply, a
combination
| of 16 zeroes and ones of data at a time is transmitted around
the
| system. The wider the virtual or literal buss (bit rate),
the
| faster things are internally and the less problem with
| bottlenecks. 32 bit is twice as fast as 16 bit (well, about,
| anyway, neglecting some added control bits) and so on.
|
| Pop
|
|
| wrote in message
|
...
| | RC [Fri, 24 Sep 2004 05:53:11 -0700]:
| | "wylbur37" wrote ...
| | Each WAV file is saved with certain parameters.
| | The following is a typical example of such parameters
....
| |
| | PCM, 44.1kHz, 16bit, stereo, 172 kbps
| |
| | I know what the "44.1kHz" (sampling rate) means,
| | and what the "172kbps" (bitrate) means.
| |
| | "172kbps" sounds like a highly compressed format such as
| |
| | More likely, the person doesn't understand or appreciate
| | using proper units:
| |
| | 176,400 bytes per second is the CD data rate
| |
| | 176400/1024 = 172.266 KB/sec (not kbps, wrong on two
counts)
| |
| |
| | For the curious, 176400 bytes/sec = 44100 Hz x 2 ch x 2
| bytes/sample/ch.
| |
| | 176400 bytes 44100 samples 2 channels 2 bytes
| | ----------- = ------------ x x ---------
| | sec sec sample /
channel
| |
| | Channels and samples cancel, leaving bytes and sec. 176400
| bytes/sec.
| | In kbps, that's 176400*8= 1411200/1000= 1411.2 kbps.
| |
| | Here, LITTLE k (as in kbps) is 1000. Little b is bits.
| | BIG K, as in KB, is 1024. Big B is bytes.
| |
| | Usually, you only see kb -OR- KB, but not kB, nor Kb. Why?
| | Because bits are usually described in 1000s (k) of,
| | and bytes in 1024s (K) of. The K symbol was purposely
| | made "close to" the standard metric k symbol (kilo = 1000)
| | since 1024 is "close to" 1000, but a little more (capital
K).
| |
| | (You'd have known this if you didn't skip that day.)
| |
| | --
| | 40th Floor - Software @ http://40th.com/
| | iPlay : the ultimate audio player for iPAQs
| | mp3, ogg, mp4, m4a, aac, wav, play & record
| | parametric eq, xfeed, reverb - all on a ppc
|
|
| The number of bits has nothing to do with speed. It is simply
the width
| of each sample. For the audio CD, there are 44,100 of these
16-bit
| samples for every second of sound. For the ultimate DVD audio
disc there
| are 192,000 24-bit samples for every second of sound. The width
of the
| sample, be it 16 bits or 24, determines the dynamic range you
can
| capture in digital audio. The rule of thumb is to multiply the
bits by 6
| to get the maximum dynamic range capability. For 16 bits, that
would be
| 16*6 or 96 db, and for 24 bits it would be 24*6=144db. In
reality, due
| to limitations in electronics and such, 24 bit systems haven't
even come
| close to 144 db capabilty. It's more like 108-110db, and 16 bit
systems
| are around 80 to 85 db.
|
| CD

You either didn't read or jumped to a conclusion. Rather than
argue, why didn't you just phrase a reasonable answer for the
guy? You're wrong, but you're right. And I'm right, in the
context he wanted to know, IMO. If not, then he has to say so.