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Gear / Technical Help => Ask The Tapers => Topic started by: wbrisette on February 20, 2005, 12:56:09 PM
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Last night at Bruce Hornsby, I had an individual as me for a patch. I tried to give her a patch via digital from my Deva, but when she tried it, it said "copy Prohibited"... I figured this was because I was feeding her an AES digital signal through a line converter. I took her digital cable and patched her from the Digital out of a DA-P1 and it still came up with the copy prohibited. I ended up giving her an analog feed, but I'm curious if anybody knows the deal on this with a D7. Seems to me that at least the DA-P1 output should have been able to pass along the digital siganal without any problems.
Wayne
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maybe your Deva is sending a signal with SCMS or some other copy protection and the p1 is able to override it but the d7 is not?
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yea it sounds like scms. was the digi out directly out of the dap1?? if so it should have worked.
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yea it sounds like scms. was the digi out directly out of the dap1?? if so it should have worked.
We tried both. I do believe the issue is the AES signal output from the DEVA. But I too would have thought that once the DA-P1 received the AES signal, it would have provided a signal without the pro information and allowed the D7 to accept it. Obviously that isn't the case.
Wayne
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I have received that message when trying to patch to a 24bit signal. Could that be your problem?
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I have received that message when trying to patch to a 24bit signal. Could that be your problem?
That's probaby it. The Deva doesn't have a way to dither the output to 16-bit, so it simply outputs 24-bit audio.
Wayne
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Perhaps only tagentially related...
I was able to feed a 24 bit signal from my Flying Calf into on older Sony MD deck...but...
On the first try - it said "No Copy" - so I read the Flying Calf manual (RTFM!) - and sure enough there is a jumper to disable SCMS (which was "on" by default...)
The MD happily accepted the signal after that...
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Perhaps only tagentially related...
I was able to feed a 24 bit signal from my Flying Calf into on older Sony MD deck...but...
On the first try - it said "No Copy" - so I read the Flying Calf manual (RTFM!) - and sure enough there is a jumper to disable SCMS (which was "on" by default...)
The MD happily accepted the signal after that...
Not really related since the Deva has no SCMS. However, it is AES, which means I have a transformer on it to bring it back to a 75 ohm level. I'm sure it's simply a combination of AES and 24 bit audio that is causing the problems.
Wayne
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It is the AES. If you feed a deck a pro signal, you can't put a non-pro deck behind it in the chain.
Tommy
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It is the AES. If you feed a deck a pro signal, you can't put a non-pro deck behind it in the chain.
Tommy
bingo.
AES can be either consumer or pro..... on the V3 at least one of the AES outputs is swicthable by using a jumper. On the minime the AES is permanently set at pro so the only decks that run from that output are pro decks (m1, dap1, hhb, d10)
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Also, the AES format includes both a electrical format (110 ohm impedence and I think a 5v signal for digital 1) and a word/information format. Things like the V3 jumpers and format converters will convert to the SPDIF electrical standard (75ohm, 0.5v), but will not convert the (24-bit? or 32 bit?) word format. Embedded in each "word" of information are the 16 bits of sound info, plus other signal info including SCMS info bits.
It might be that you were using a 24-bit music format, I don't know how that affects a D7/D8 deck. But if the DEVA is sending a professional signal that doesn't even include the bits for SCMS, the P1 will read that (since it is a pro deck), but it will just pass along the data without adding the SCMS bits into the data words. A D7/D8 getting this signal with no info on SCMS whatsoever will read that as unacceptable from a SCMS standpoint and will give the "copy prohibit" message. Bottom line, even though the P1 might have acted to change the electrical signal to that conforming with SPDIF, it won't alter the pro data format information.