On Fri, 17 Jul 2015 23:45:46 -0700, Phil Allison wrote:

Johnny B Good wrote:

====snip====

The remaining issue with DACs was the analogue output stage clipping
that afflicted some of the earlier products due to inadequate voltage
rail provisioning derived from the "Join the dots" peak amplitude
calculations by some rather naive designers who didn't fully understand
the process of handling a bandwidth limited analogue signal encoded
into the digital domain.

** Not real sure what you are on about here, but the maximum signal
level possible from a CD player is 2Vrms or 2.83V peak. Given that most
players have dual 12 or 15 volt supplies for the op-amps, there is no
such issue.


The "Join the dots" approach to deciding the clipping headroom required
in the DAC stages of *some* models of CD players would normally have
sufficed with most music material. The trouble only really became evident
as a result of the "Loudness Wars" techniques where the digital
processing permitted 'soft limiting' to be taken to such an extreme as to
be just shy of 'clipping'.

It was the resulting steep leading transients on 'soft limited'
waveforms that caught out the marginally sufficient of clipping headroom
based DAC/ output buffer amp designs.

In fact this deficiency in some models of CD player only became evident
as a result of the research into the undesired effects of such dynamic
range compression being taken to extremes by the perpetrators of the
"Loudness War".

Unfortunately, I don't seem to have the article(s) in question
bookmarked to offer as a citation and googling "Loudness War" results in
more than enough hits to choke a Blue Whale to death on if each hit
represented just a single minnow's worth of protein.

--
Johnny B Good