[Don Pearce]

Richard Crowley wrote:
"Don Pearce" wrote ...
Arny Krueger wrote:
"Don Pearce" wrote ...
Joe the audio guy wrote:
Another quick question: Is Dolby B/C available as software and, if
not, why?

Joe
It would be totally pointless. Once you have the signal rendered into
numbers, there are no longer any dynamic range limitations that would
merit Dolby (B or C).
What about decoding existing Dolby-encoded recordings?

Do you really not see the benefit of a software-based solution.

How would you perform the calibration?

Same way you would with hardware-based Dolby decoding.
(whether accurate or otherwise).


Everybody is clearly reading this question differently to the way I am.
If the question is "Would it be a good idea to have an application that
could rescue a tape recorded in B/C when a proper playback system is
unavailable?" Then yes, I can see that it might have some limited
application for a while.

But that is not how I read it. My understanding of the question is that
it is asking if it would be a good idea to routinely offer Dolby B and C
as companding methods in a DAW, on the basis that they might offer some
sonic advantage. The answer to that is a definite No.

d

[William Sommerwerck]

Everybody is clearly reading this question differently to the way I am.
If the question is "Would it be a good idea to have an application that
could rescue a tape recorded in B/C when a proper playback system
is unavailable?" Then yes, I can see that it might have some limited
application for a while.

But that is not how I read it. My understanding of the question is that
it is asking if it would be a good idea to routinely offer Dolby B and C
as companding methods in a DAW, on the basis that they might offer
some sonic advantage. The answer to that is a definite No.

No offense, but I think you misread it.

By the way, many years ago I tried superimposing dbx II on top of Dolby B,
the idea being that the Dolby would reduce the noise sufficiently to prevent
audible breathing from the dbx. The results were horrendous.

[Don Pearce]

William Sommerwerck wrote:
Everybody is clearly reading this question differently to the way I am.
If the question is "Would it be a good idea to have an application that
could rescue a tape recorded in B/C when a proper playback system
is unavailable?" Then yes, I can see that it might have some limited
application for a while.

But that is not how I read it. My understanding of the question is that
it is asking if it would be a good idea to routinely offer Dolby B and C
as companding methods in a DAW, on the basis that they might offer
some sonic advantage. The answer to that is a definite No.

No offense, but I think you misread it.


Not offended - but here is the original question "Another quick
question: Is Dolby B/C available as software and, if not, why?". I
think my interpretation is probably rather more reasonable (in that it
doesn't add a whole load of unstated stuff) than the 'rescuing old
tapes' one.

By the way, many years ago I tried superimposing dbx II on top of Dolby B,
the idea being that the Dolby would reduce the noise sufficiently to prevent
audible breathing from the dbx. The results were horrendous.



I can imagine. I still have an analogue dbx companding box I made many,
many years ago with some purpose-designed vca chips - can't remember the
numbers now. It worked pretty well with my cassette deck, but not if
Dolby was enabled too.

d

[Arny Krueger]

"Don Pearce" wrote in message
...
Everybody is clearly reading this question differently to the way I am. If
the question is "Would it be a good idea to have an application that could
rescue a tape recorded in B/C when a proper playback system is
unavailable?" Then yes, I can see that it might have some limited
application for a while.

That's how I see the question.

But that is not how I read it. My understanding of the question is that it
is asking if it would be a good idea to routinely offer Dolby B and C as
companding methods in a DAW, on the basis that they might offer some sonic
advantage. The answer to that is a definite No.

I agree with that, too. Dolby A, B, C, and S as well as the various forms of
DBX were work-arounds for a problem that has been solved for all practical
purposes by means of modern digital recording.

One interesting spec comes from one of the Dolby boxes that supports A, B,
C, and S. They seem to be claiming 100's of dBs of dynamic range. If I was
in some kind of esoteric situation where a mere 120 dB wouldn't do the job,
I might think about dredging up one of these boxes and see what it could do.
;-)

[Richard Crowley]

"Don Pearce" wrote ...
Everybody is clearly reading this question differently to the way I am. If
the question is "Would it be a good idea to have an application that could
rescue a tape recorded in B/C when a proper playback system is
unavailable?" Then yes, I can see that it might have some limited
application for a while.

But that is not how I read it. My understanding of the question is that it
is asking if it would be a good idea to routinely offer Dolby B and C as
companding methods in a DAW, on the basis that they might offer some sonic
advantage. The answer to that is a definite No.

Yes, of course. It would be absurd to try to use any kind of traditional
Dolby noise reduction when recording digitally. Which is why we all
jumped to the obvious assumption that the OP was talking about the
decoding of previously recorded tapes. Admittedly, that assumption
should have been explicitly stated.

[Scott Dorsey]

Richard Crowley wrote:

Yes, of course. It would be absurd to try to use any kind of traditional
Dolby noise reduction when recording digitally. Which is why we all
jumped to the obvious assumption that the OP was talking about the
decoding of previously recorded tapes. Admittedly, that assumption
should have been explicitly stated.

Folks actually DID try using NR through digital systems back in the
early eighties. I knew a couple folks who used DBX systems running into
PCM F-1 machines and it did seem to tame some of the low-level buzziness
problems of the F-1.

Thank God that's all over.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Don Pearce]

Richard Crowley wrote:
"Don Pearce" wrote ...
Everybody is clearly reading this question differently to the way I am. If
the question is "Would it be a good idea to have an application that could
rescue a tape recorded in B/C when a proper playback system is
unavailable?" Then yes, I can see that it might have some limited
application for a while.

But that is not how I read it. My understanding of the question is that it
is asking if it would be a good idea to routinely offer Dolby B and C as
companding methods in a DAW, on the basis that they might offer some sonic
advantage. The answer to that is a definite No.

Yes, of course. It would be absurd to try to use any kind of traditional
Dolby noise reduction when recording digitally. Which is why we all
jumped to the obvious assumption that the OP was talking about the
decoding of previously recorded tapes. Admittedly, that assumption
should have been explicitly stated.



I always think it is better to assume that the poster meant what he said
and answer that, rather than instantly assuming he must have meant
something different. He can always clarify later.

d

[Mike Rivers]

Don Pearce wrote:

I always think it is better to assume that the poster meant what he said
and answer that, rather than instantly assuming he must have meant
something different. He can always clarify later.

Far too many posters here don't know the proper, or at least widely
accepted, terminology and can often be misleading if you take their
posts too literally. How many people write "jack" when they mean "plug,"
or "mix" when they mean "edit" or vice versa?

--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)

[Don Pearce]

Mike Rivers wrote:
Don Pearce wrote:

I always think it is better to assume that the poster meant what he
said and answer that, rather than instantly assuming he must have
meant something different. He can always clarify later.

Far too many posters here don't know the proper, or at least widely
accepted, terminology and can often be misleading if you take their
posts too literally. How many people write "jack" when they mean "plug,"
or "mix" when they mean "edit" or vice versa?


Of course, but this wasn't simply a matter of terminology but one of
basic concept; that of using Dolby B or C in the digital domain.

d