In article ,
Serge Auckland wrote:
Digital outputs are referred to maximum digital output (when all the
bits are 1) and that is called 0dBFS (0dB Full Scale). It has NO
analogue equivalent, as analogue can keep getting bigger without limit,
digital can't get any bigger than when all the bits are 1. In
Digital-Analogue conversion, a number of different conversion levels
have become more-or-less standard. The EBU (European Broadcasting
Union) have defined 0dBFS digital to mean +18dBu analogue after
conversion. The USA prefers that 0dBFS = +24dBu because that provides
20dB headroom above 0VU. A few dissidents prefer +25dBu as that's 1dB
better than +24...........

It's quite interesting to look at levels off Freeview. I lined up the
workshop receiver to read PPM 4 on a rare occasion when there was a test
card and line up tone available. And as expected TV progs peak to no more
than PPM 6. But some of the radio ones wrap the PPMs round the end stops.
;-)

My best Freeview receiver out of several is a Sony VTX-D800U and when I
changed it from the previous freebie Sagem which kept crashing I
immediately noticed the audio level was low. Switch the set from the same
channel on analogue to Freeview via a SCART and the difference was too
much. Correspondence with Sony showed that they thought the TV
broadcasters would peak to 0dBFS on FreeView instead of using the normal
EBU line up of peak being -10 dBFS.

--
*Re-elect nobody

Dave Plowman London SW
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