I'm looking for current CD or DVD players that do report the spdif
validity flag from the coaxial digital output.

It's for loading into a workstation like Sadie. I have one player left
here that does, a Pioneer DV-340, but it has terrible error correction
so the smallest defect in a CD is audible as a glitch or skip (Pioneer
so far has the honor of worst CD playback I can find, a very valuable
thing in my business). OTOH, I can take any cheap $75 player that will
correct practically every error but they don't report the validity
flag even on a terribly damaged, glitching, muting CD.

Can anyone confirm if your current player reports validity errors?

Thanks for any help

George @ _ amtechdisc.com

George wrote:
I'm looking for current CD or DVD players that do report the spdif
validity flag from the coaxial digital output.

It's for loading into a workstation like Sadie. I have one player left
here that does, a Pioneer DV-340, but it has terrible error correction
so the smallest defect in a CD is audible as a glitch or skip (Pioneer
so far has the honor of worst CD playback I can find, a very valuable
thing in my business). OTOH, I can take any cheap $75 player that will
correct practically every error but they don't report the validity
flag even on a terribly damaged, glitching, muting CD.

Can anyone confirm if your current player reports validity errors?

Thanks for any help

George @ _ amtechdisc.com

The validity flag can be used for instance to indicate if a specific
sample is not valid when it is non-audio. This is coded in the channel
status (C) bits as well, but these are appended to the samples in a
block of 192 samples. So the Validity flag is can give immediate warning
per sample whereas the channel status only per block.


As far as I know the Validity flag is not used to indicate whether the
error correction/ concealment has been done. It might indicate non
validity at mutes however.

my regards

Bert Kraaijpoel

Bert Kraaijpoel wrote:

The validity flag can be used for instance to indicate if a specific
sample is not valid when it is non-audio. This is coded in the channel
status (C) bits as well, but these are appended to the samples in a
block of 192 samples. So the Validity flag is can give immediate warning
per sample whereas the channel status only per block.


As far as I know the Validity flag is not used to indicate whether the
error correction/ concealment has been done. It might indicate non
validity at mutes however.


Hi Bert,

I think I used the wrong word: flag. Like you said, there is a validity
flag embedded in the CD. That is not what I'm looking for. I'm looking
for a CD player that passes on an indication of errors or concealment.

I can confirm that a disc that has proven CU errors, too many C2 (E22)
errors, or bizarre jitter, does cause a "validity error" to pop up on my
Sadie system with various CD players (and DAT players) I have used, but
not with the new players I have tried. Also, a disc that was burned by
some software will do the same between tracks. I used to get a 'tick' at
those points but I guess my Pioneer mutes so I don't hear or see it.
Maybe the burning software did set the validity flag when it made the
disc. That will be interesting to check.


Thanks for your response.

George

George wrote:

Hi Bert,

I think I used the wrong word: flag. Like you said, there is a validity
flag embedded in the CD. That is not what I'm looking for. I'm looking
for a CD player that passes on an indication of errors or concealment.

I can confirm that a disc that has proven CU errors, too many C2 (E22)
errors, or bizarre jitter, does cause a "validity error" to pop up on my
Sadie system with various CD players (and DAT players) I have used, but
not with the new players I have tried. Also, a disc that was burned by
some software will do the same between tracks. I used to get a 'tick' at
those points but I guess my Pioneer mutes so I don't hear or see it.
Maybe the burning software did set the validity flag when it made the
disc. That will be interesting to check.


Thanks for your response.

George


Hi George,

I had to look up the eact meaning of E22 etc again. I guess error
correction is ok with E22 errors. If I am not mistaken only with E32 the
Concealment Unit gets busy.
Nice to learn that your Pioneer player sets the Validy bit (or flag...)
to Invalid when the CU cannot cope with the errors anymore.

I feel sorry that I don't know of another player that does so as well.


my regards,
Bert

George wrote:

Also, a disc that was burned by
some software will do the same between tracks. I used to get a 'tick' at
those points but I guess my Pioneer mutes so I don't hear or see it.

The 'tick' are common for hifi CD recorders when operating in Track At
Once mode. TAO usually leave a piece blank on the CD and some hifi CD
recorder backup a litte when starting a new track. This eliminates
the hickup on some old audio CD player when they encounter a blank
area but the backup will generate some invalid bytes - which should
get corrected at the E22 stage. If E22 fails the CD player should mute
and set the validity flag in the digital output. So your Pioneer player
seems to behave correctly.

Maybe the burning software did set the validity flag when it made the
disc. That will be interesting to check.

There is no validity flag on a CD. There is a "pause" flag though that
should cause the CD player to mute, but this is rarely used to my
knowledge. Professional CD mastering software gets you access on the
P bit but CD burning software usually doesn't support that.

My old Denon CD player rises the validity flag in the digital output
when interpolating (error concealments) fails due to the length of
the error. When recording such a digital data stream to my DAT
recorders, both the Sony and the TASCAM enter pause mode until that
flag gets cleared.

Sad to read that more recent CD player have a poor implementation of
the protocol.

Norbert