Hi,

I heard different things about the format of spdif and aes/ebu. Beeing
the same, almost the same and totaly different. The "physical layer" of
course is different, but what about the protocol?

I want to convert the spdif out (optical or koax) of my SPL gainstation
AD (96kHz/24bit) to feed my 896 MOTU having only AES inputs (XLR).

Somebody said, it is possible to do that without format converting,
that is only with a RCA-to-XLR cable adaptor? I don't think so...
Will the MOTU accept consumer spdif over professional AES ins?

What is the cheapest solution the convert SPDIF to AES? I thought of a
Behringer Ultramatch. Do you think my audio signal has any impact in
terms of quality when going trough a Behringer? The unit claims to have
Jitter removement...

An other solution for me is to have a really basic USB ASIO interface
having a SPDIF in. But I cant find one in a store or ebay...

Note it MUST be compatible with 96/24.

How would you solve this?

Thanks,

Lukas

leutholl wrote:

I heard different things about the format of spdif and aes/ebu. Beeing
the same, almost the same and totaly different. The "physical layer" of
course is different, but what about the protocol?

You're talking like a networking person. The audio data is the same for
both, but there's a difference between the significance of the other
bits in the data frame. Some devices and programs ignore those bits,
others care about them. The hardware interface (physical layer?) is
different but not all that different.

I want to convert the spdif out (optical or koax) of my SPL gainstation
AD (96kHz/24bit) to feed my 896 MOTU having only AES inputs (XLR).

Somebody said, it is possible to do that without format converting,
that is only with a RCA-to-XLR cable adaptor? I don't think so..

Most of the time it works. I always suggest trying the simple way
first.

Will the MOTU accept consumer spdif over professional AES ins?

Check the MOTU control panel. There may be a switch in there. More
often than not, the switch is for the output data format and it doesn't
care about what's coming in. For more information, RTFM.

What is the cheapest solution the convert SPDIF to AES?

A properly wired cable, if it works. Next up is probably a transformer
(usually called a "balun" in this context). M-Audio makes a hardware
converter that also accommodates the optical interface on the S/PDIF
side. The Behnringer might also work. And it shouldn't affect "quality"
as long as you get audio through it. None of these fixers will.

leutholl wrote:

I heard different things about the format of spdif and aes/ebu. Beeing
the same, almost the same and totaly different. The "physical layer" of
course is different, but what about the protocol?

Okay, there isn't any more S-PDIF any more. And there isn't any AES/EBU.

There is IEC-458. And there is IEC-458 over 75 ohm coax with consumer
subcode (what used to be S-PDIF) and IEC-458 over 110 ohm twinax with
professional subcode (what used to be AES/EBU).

But there is ALSO professional subcode over 75 ohm coax and consumer
subcode over 110 ohm twinax. These weren't valid under the S-PDIF and
AES/EBU standards, even though some equipment could use them. They
are, however, valid under the decade-old IEC-458.

I want to convert the spdif out (optical or koax) of my SPL gainstation
AD (96kHz/24bit) to feed my 896 MOTU having only AES inputs (XLR).

Somebody said, it is possible to do that without format converting,
that is only with a RCA-to-XLR cable adaptor? I don't think so...
Will the MOTU accept consumer spdif over professional AES ins?

Are you sure the SPL is really giving consumer subcode? Most modern
computer interfaces will handle either consumer or professional subcode
with no problem. Pretty much anything made in the last decade conforms
to the IEC-458 spec. So I wouldn't worry about it, and I'd just use
the transformer adaptor.

Note it MUST be compatible with 96/24.

Presumably the single-wire 96/24 standard and not the double one!
That's another whole nightmarish story. But most stuff today should
be fine. This isn't 1988, when the standards were very much in flux
and Panasonic was sending folks to AES shows to urge them to change
the standard to make the SV3700 acceptable under it....
--scott

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

Am 21 Feb 2006 19:24:54 -0500 schrieb Scott Dorsey:

leutholl wrote:

I heard different things about the format of spdif and aes/ebu. Beeing
the same, almost the same and totaly different. The "physical layer" of
course is different, but what about the protocol?

Okay, there isn't any more S-PDIF any more. And there isn't any AES/EBU.

There is IEC-458. And there is IEC-458 over 75 ohm coax with consumer
subcode (what used to be S-PDIF) and IEC-458 over 110 ohm twinax with
professional subcode (what used to be AES/EBU).

But there is ALSO professional subcode over 75 ohm coax and consumer
subcode over 110 ohm twinax. These weren't valid under the S-PDIF and
AES/EBU standards, even though some equipment could use them. They
are, however, valid under the decade-old IEC-458.

I want to convert the spdif out (optical or koax) of my SPL gainstation
AD (96kHz/24bit) to feed my 896 MOTU having only AES inputs (XLR).

Somebody said, it is possible to do that without format converting,
that is only with a RCA-to-XLR cable adaptor? I don't think so...
Will the MOTU accept consumer spdif over professional AES ins?

Are you sure the SPL is really giving consumer subcode? Most modern
computer interfaces will handle either consumer or professional subcode
with no problem. Pretty much anything made in the last decade conforms
to the IEC-458 spec. So I wouldn't worry about it, and I'd just use
the transformer adaptor.

Note it MUST be compatible with 96/24.

Presumably the single-wire 96/24 standard and not the double one!
That's another whole nightmarish story. But most stuff today should
be fine. This isn't 1988, when the standards were very much in flux
and Panasonic was sending folks to AES shows to urge them to change
the standard to make the SV3700 acceptable under it....
--scott

Thanks a lot for this! I will try to get a transformer/balun/impedance
match/../..
I'm happy to live in 2006, but I never thought that it will be so easy. ;-)

What about the USB interface? Is there something having SPDIF (sorry
IEC-458) I/O and USB with ASIO driver on the other side? If not, I will
build one, this can't be so difficult.

Lukas
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Scott Dorsey wrote:

Presumably the single-wire 96/24 standard and not the double one!
That's another whole nightmarish story. But most stuff today should
be fine.

Didn't Tascam recently ship a DVD-Audio recorder that uses two-wire
24/96? g

--
ha

Am Wed, 22 Feb 2006 02:24:06 GMT schrieb hank alrich:

Scott Dorsey wrote:

Presumably the single-wire 96/24 standard and not the double one!
That's another whole nightmarish story. But most stuff today should
be fine.

Didn't Tascam recently ship a DVD-Audio recorder that uses two-wire
24/96? g

96/24 is possible over a two-wire cable! At least my gainstation does it!
Lukas
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Am Wed, 22 Feb 2006 18:13:34 GMT schrieb Lorin David Schultz:

"leutholl" wrote:

I want to convert the spdif out (optical or koax) of my SPL
gainstation AD (96kHz/24bit) to feed my 896 MOTU having only AES
inputs (XLR).

Somebody said, it is possible to do that without format converting,
that is only with a RCA-to-XLR cable adaptor? I don't think so...
Will the MOTU accept consumer spdif over professional AES ins?


Try it. Some devices actually work perfectly this way. I don't know
why some devices seem to work and others don't, but given how easy it is
to check, I'd give it a try. If it doesn't work you haven't lost
anything except a few minutes.

The next least expensive solution is a Canare transformer. It converts
unbalanced 75 ohm to balanced 110 ohm AES/EBU. So far I haven't come
across ANY device that doesn't work with those, but I have only seen
them in use with expensive studio gear. I don't know if acceptance of
that conversion is similarly device-specific.



After that I'd start searching Google for active converters, but since
I've never needed one, I can't recommend a specific unit.

Thanks so far.
Can I use a passive DI box, this is make the signal balanced?!?! What
peak-to-peak voltage do I have to expect?
I have to go from SPDIF to AES not from AES to SPDIF...
Lukas
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leutholl wrote:
Can I use a passive DI box, this is make the signal balanced?!?!

Geez, will you quit trying to make this complicated? Just get an
RCA-XLR cable or adapter.

A DI has too great a ratio (either stepping up or stepping down). You
really don't need to change the voltage very much if at all. And there
may be no need to balance the line. And by all means, try it before you
need to use it. When you have a gig or a fidgity customer waiting to
record is not the time to hope that youre carefully researched but
untested solution works.

What peak-to-peak voltage do I have to expect?

About 5 volts. You don't need to get an electrical permit from the
county or even call an electrician to do the wiring.

leutholl wrote:
Can I use a passive DI box, this is make the signal balanced?!?! What
peak-to-peak voltage do I have to expect?

No. The digital audio signal is 4 MHz wide. A passive DI with an
audio transformer will not work.

I have to go from SPDIF to AES not from AES to SPDIF...

So buy one of the Canare gadgets with a wideband pulse transformer in it.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

"leutholl" wrote:

Can I use a passive DI box, this is make the signal balanced?!?!

What? I have no idea what you mean...



What peak-to-peak voltage do I have to expect?

From what? The S/PDIF signal? Look up the spec... roughly half a volt
or so. I don't know how it matters though. Either the receiver will
lock to it or it won't. If it won't, the transformer will take care of
the voltage issue.



I have to go from SPDIF to AES not from AES to SPDIF...

Lukas, buddy... just PLUG IT IN and see if it works. Quit worrying so
much. It costs you nothing to try that, and if it works the rest of the
discussion is moot.

For whatever it's worth, there's a basic description of the process on
the Rane web site at http://www.rane.com/note149.html

--
"It CAN'T be too loud... some of the red lights aren't even on yet!"
- Lorin David Schultz
in the control room
making even bad news sound good

(Remove spamblock to reply)

Am 21 Feb 2006 16:00:26 -0800 schrieb leutholl:

Hi,

I heard different things about the format of spdif and aes/ebu. Beeing
the same, almost the same and totaly different. The "physical layer" of
course is different, but what about the protocol?

I want to convert the spdif out (optical or koax) of my SPL gainstation
AD (96kHz/24bit) to feed my 896 MOTU having only AES inputs (XLR).

Somebody said, it is possible to do that without format converting,
that is only with a RCA-to-XLR cable adaptor? I don't think so...
Will the MOTU accept consumer spdif over professional AES ins?

What is the cheapest solution the convert SPDIF to AES? I thought of a
Behringer Ultramatch. Do you think my audio signal has any impact in
terms of quality when going trough a Behringer? The unit claims to have
Jitter removement...

An other solution for me is to have a really basic USB ASIO interface
having a SPDIF in. But I cant find one in a store or ebay...

Note it MUST be compatible with 96/24.

How would you solve this?

Thanks,

Lukas

OK. Final statement to this thread!

I bought a Neutrik NADITBNC-M impedance matcher (110 to 75 Ohm) with BNC to
XLR.
I connected the GainSation AD to my MOTU 896 (AES/EBU in) and it worked!
Also with 96/24.

Thanks a lot for every hint you gave, it saved my a lot of money!

Lukas

leutholl wrote:
Am 21 Feb 2006 16:00:26 -0800 schrieb leutholl:

I bought a Neutrik NADITBNC-M impedance matcher (110 to 75 Ohm) with BNC to
XLR.
I connected the GainSation AD to my MOTU 896 (AES/EBU in) and it worked!
Also with 96/24.

Thanks a lot for every hint you gave, it saved my a lot of money!

You might have saved even more money if you had tried a transformerless
adapter, but if you're happy, we're happy.