Re: Analog vs. Digital defined (fwd)

James Rogers (jarogers@cisco.com)
Thu, 05 Mar 1998 14:42:19 -0800


At 01:52 PM 3/5/98 -0800, JL AUDIO wrote:
>
>You are right in some respects. There is much more to it than you
>are taking into account, though. From my personal knowladge on
>automotive auto sound. 100 bit d/a converters are available and are
>in use though not very widely. i belive there is a home theater
>company in England that has produced and marketed a DVD player with
>"true" sound capibility. Many car stereos have 20 bit d/a
>converters, even a couple. The main reason the 100 bit's are not
>used is the cost to sound quality ratio. It just is not practical to
>have absolutley clear sound when the human cannot recognize the
>differance.

Most experts put the human limit for resolving audio in the 20 to 24-bit
range. Even ultra high-end studio equipment does not exceed 24-bits because
there is no practical reason to.

Also, having 20-bit converters in a car stereo is a total waste. You need a
minimum of 1500 cubic feet (rule of thumb) of enclosed space to reproduce a
sound without it being seriously colored and distorted by the enclosing
space. While the sound may be *generated* with high precision, the human
perception of the sound will be very colored and inaccurate due to the small
environment creating a very uneven frequency response. A good 16-bit
converter is more than enough for any vehicle. It never ceases to amaze me
that so many self-styled car audiophiles know so little about the
fundamentals of audio reproduction. The environment has far more to do with
the quality of the audio than the quality of the electronics generating it,
esp. considering the average quality of audio electronics these days. The
quality of the electronics only starts to become very important when your
sound-space becomes relatively large i.e. much larger than the enclosed
space of your car.

>hopefully this is the topic you were on. If not, well you learned
>something.

Well, it wasn't really the topic I was on, but most of my experience with
the topic did come from a lot of work in the audio field.

-James Rogers
jamesr@best.com