Elektron Musical Instruments

On Wed, 04 Oct 2006 21:24:51 -0500 Mark Rivera <marr@...> wrote:

> Re the bit rate itself, I think Wikipedia (and many, many other online 
> resources may be wrong).
> 
> The MIDI Manufacturers Association states "31.25 Kbits/sec" at: 
> http://www.midi.org/about-midi/tutorial/tutor.shtml .
> 
> Wikipedia states 31,250 bits per second.
> 
> Since this is a computer kilo (1024), and not a metric kilo (1000), I 
> think the bit rate for MIDI may actually be 32000 bits per second.
> 
> Does anyone have the official MIDI Spec 1.0 book? I'm looking for an 
> official source that says the bit rate without stating it in terms of
> kilos.

Actually the "computer kilo" 1024 is used only for memory capacity and 
displaying harddrive capacity. On the other hand, the actual capacity printed 
in the harddrives and dvd discs is multiple of 1000. For example, 4,7 GB DVD is 
only 4,4 gigabytes when displayed in operating system (which uses 1024).

In transmission multiplier of 1000 is used. For example, ISDN line is 64kbit 
which is 64,000 bits not 65,536. Thus your 1 Mbit ADSL connection can transfer 
~122 kilobytes/sec instead of 128 kilobytes.
 
Thus, the 31,250 bits per second is probably correct. Try googling "midi 
transfer rate 31250" and you find a lot of entries, many for hardware 
implementations. With "32000" you get very few...

I remember tackling with these same issues in my studies... :)

> thanks,
> Mark
> 
> 

- sampsa

-- 
____________________
Sampsa Lehtonen