Subject: Re: long distance AES/EBU ?
From: mkp@kayak.engr.sgi.com (Michael K. Poimboeuf)
Date: 19 Jan 1997 07:12:49 GMT
Message-ID: <5bshhh$kgb@fido.asd.sgi.com>


In article <72477.3077-ya02408000R1601971707390001@news.interport.net>,
72477.3077@compuserve.com writes:
> I'm looking for information on how far AES/EBU signal can be run without
> "problems" on either Belden or Mogami AES/EBU cable?  Beyond this distance,
> how does one compensate?
> 
> -- 
> Fritz
> 
Look at the AES-3id information document on doing long runs with AES3.
You can find the abstract at www.aes.org 
This is a coaxial version for the physical layer of AES3 instead of the
twisted pair in the older implementions.

The most bullet-proof way to do these long runs is to use coaxial digital
video cable.

I've been doing 1km runs without equalization without problems. I was 
talking to engineers from Pioneer who said that there are two Japan network
TV high rises wired per AES-3id, and they had several runs of 10km.

I've heard of runs of 1,000km in the UK (equalized and hand tweaked). 

AES-3id in a nutshell: Coaxial 75ohm RG59 or serial digital video cable;
		       1vpp single ended on TXTR;
		       350mvpp mimimum eye opening on RCVR;
mkp's comments: Don't try to use analog video DA's as suggested in the 
information document; And thus, don't worry about doing the extreme 
slew rate limiting that AES-3id recommends. Do use very high quality
video cable, and stick to well terminated 75 ohm point-to-point runs.

--
Michael K. Poimboeuf mkp@sgi.com
Digital Media
Desktop Systems Division
Silicon Graphics Inc. Mtn View California
---------------------------------------------------------

Subject: Re: Convert AES/EBU to S/PDIF and back?
From: Carl H Scheuermann <Carl.Scheuermann@informatik.uni-jena.de>
Date: Mon, 08 Sep 1997 17:36:00 +0200
Message-id: <34141B60.DD1FDD24@informatik.uni-jena.de>

Erich Specht wrote:
> I was wondering if anyone knows of any device that can convert a digital
> signal between S/PDIF and AES/EBU.  I have a nice DAT machine with
> AES/EBU connections and will be purchasing Layla which only has S/PDIF.
> Is there any hope of using them both without going analog?


In the July/August edition of "Elektor" magazine (published in
several European countries and languages) there were two quite
simple schematics of how to convert AES/EBU to SP/DIF and vice
versa. It is just an electrical conversion (balanced <-> unbalanced),
since it is they same data format (so the article claimed).

If you can get hold of this issue (sorry, I don't have it)
it should do what yuo need (the circuits are really easy to build).

Hope that helped,
Carl
--
Dipl. Ing. Carl H. Scheuermann
LS f. Rechnerarchitektur, Friedrich-Schiller-Univ. Jena
Carl.Scheuermann@uni-jena.de, C.H.Scheuermann@ieee.org
PGP-Public-key: http://www2.informatik.uni-jena.de/~carls/pubkey.asc


  Subject:
Re: Convert AES/EBU to S/PDIF and back?
From: scott@basis.com (Scott Amspoker)
Date: Mon, 08 Sep 1997 22:02:21 GMT
Message-id: <341e75a2.21921294@basis.basis.com>

Carl H Scheuermann <Carl.Scheuermann@informatik.uni-jena.de> wrote:

>In the July/August edition of "Elektor" magazine (published in
>several European countries and languages) there were two quite
>simple schematics of how to convert AES/EBU to SP/DIF and vice
>versa. It is just an electrical conversion (balanced <-> unbalanced),
>since it is they same data format (so the article claimed).

They are not the same data format.  However, they are quite similar.  A
simple physical conversion will not necessarily do the trick.


Scott Amspoker         |
scott@basis.com        | Expressed opinions are mine
http://www.rt66.com/sda| and not those of my employer.


  Subject:
Re: Convert AES/EBU to S/PDIF and back?
From: Carl H Scheuermann <Carl.Scheuermann@informatik.uni-jena.de>
Date: Mon, 08 Sep 1997 17:36:00 +0200
Message-id: <34141B60.DD1FDD24@informatik.uni-jena.de>

Erich Specht wrote:
> I was wondering if anyone knows of any device that can convert a digital
> signal between S/PDIF and AES/EBU.  I have a nice DAT machine with
> AES/EBU connections and will be purchasing Layla which only has S/PDIF.
> Is there any hope of using them both without going analog?


In the July/August edition of "Elektor" magazine (published in
several European countries and languages) there were two quite
simple schematics of how to convert AES/EBU to SP/DIF and vice
versa. It is just an electrical conversion (balanced <-> unbalanced),
since it is they same data format (so the article claimed).

If you can get hold of this issue (sorry, I don't have it)
it should do what yuo need (the circuits are really easy to build).

Hope that helped,
Carl
--
Dipl. Ing. Carl H. Scheuermann
LS f. Rechnerarchitektur, Friedrich-Schiller-Univ. Jena
Carl.Scheuermann@uni-jena.de, C.H.Scheuermann@ieee.org
PGP-Public-key: http://www2.informatik.uni-jena.de/~carls/pubkey.asc


  Subject:
Re: Convert AES/EBU to S/PDIF and back?
From: scott@basis.com (Scott Amspoker)
Date: Mon, 08 Sep 1997 22:02:21 GMT
Message-id: <341e75a2.21921294@basis.basis.com>

Carl H Scheuermann <Carl.Scheuermann@informatik.uni-jena.de> wrote:

>In the July/August edition of "Elektor" magazine (published in
>several European countries and languages) there were two quite
>simple schematics of how to convert AES/EBU to SP/DIF and vice
>versa. It is just an electrical conversion (balanced <-> unbalanced),
>since it is they same data format (so the article claimed).

They are not the same data format.  However, they are quite similar.  A
simple physical conversion will not necessarily do the trick.


Scott Amspoker         |
scott@basis.com        | Expressed opinions are mine
http://www.rt66.com/sda| and not those of my employer.


  Re:
Convert AES/EBU to S/PDIF and back?


Thema:	Simple buffer splitter box for AES/EBU sync signals
Von:	"Bernard Reeve" <bern@euphonix.com>
Datum:	13 Oct 1997 17:37:54 GMT

Does anyone know of a simple box that can accept an AES/EBU Sync signal,
buffer it, then provide multiple copies of it for distribution purposes.

I am looking for an off the shelf solution, probably in a simple 1U 19"
form factor.

Thanks
Bern

Thema:	Re: Simple buffer splitter box for AES/EBU sync signals
Von:	shlampen@aol.com (ShLampen)
Datum:	14 Oct 1997 20:57:54 GMT

In article <01bcd7fe$b9a9a8a0$c20314cf@paeebr95.euphonix.com>, "Bernard
Reeve" <bern@euphonix.com> writes:

>(snip)

Wouldn't a passive AES splitter do this?  ETS makes them in both XLR and
coax formats  1-800-752-8208.


Steve Lampen
Technology Development Manager
Belden Wire & Cable Co.
www.belden.com
My new book, "Wire, Cable, and Fiber Optics for Video and Audio Engineers"
has just been published by McGraw-Hill.

Thema:	Re: Simple buffer splitter box for AES/EBU sync signals
Von:	kludge@netcom.com (Scott Dorsey)
Datum:	Mon, 13 Oct 1997 20:14:05 GMT

In article <01bcd7fe$b9a9a8a0$c20314cf@paeebr95.euphonix.com> "Bernard Reeve" <bern@euphonix.com> writes:
(snip)

Use the Canare transformers to unbalance it to a 75 ohm line, then use
a video DA to distribute it out.  Cheap and easy.
--scott
-- 
"C'est un Nagra.  C'est suisse, et tres, tres precis."


Thema:	Re: AES/EBU wiring advice?
Von:	mihartkopf@aol.com (Mihartkopf)
Datum:	23 Oct 1997 06:18:44 GMT

Im Artikel <344CAE60.2FBD@exp.net>, music@exp.net schreibt:

>Yesterday someone posted a recommendation that AES/EBU wiring between
>the in/out of a DAT machine to a digital in/out soundcard be no longer
>than 5 meters (approx. 16 feet).  What happens if a 20ft cable is used? 
>Also, what brand of wiring is recommended...and where is a good source
>to buy?
>
>Thanks 
>FJ

2 years ago I've done it with a 10 meters somewhere-lying-around
microphone cable and it worked fine.

Michael Hartkopf

++++++++++++++++++++++++++++++
data of many many many microphones at
http://members.aol.com/mihartkopf/
++++++++++++++++++++++++++++++

Thema:	Re: AES/EBU wiring advice?
Von:	shlampen@aol.com (ShLampen)
Datum:	24 Oct 1997 14:43:17 GMT

In article <344CAE60.2FBD@exp.net>, music@exp.net writes:

>Yesterday someone posted a recommendation that AES/EBU wiring between
>the in/out of a DAT machine to a digital in/out soundcard be no longer
>than 5 meters (approx. 16 feet).  What happens if a 20ft cable is used? 
>Also, what brand of wiring is recommended...and where is a good source
>to buy?
>
Isa this balanced or unbalanced?  True AES/EBU or really S/PDIF? If it is
AES/EBU or S/PDIF, I have no idea why the 16 ft. limit.  


Steve Lampen
Technology Development Manager
Belden Wire & Cable Co.
www.belden.com
My new book, "Wire, Cable, and Fiber Optics for Video and Audio Engineers"
has just been published by McGraw-Hill.

Thema:	Re: AES/EBU wiring advice?
Von:	film2@emedia.net (Emmett Gray)
Datum:	Sun, 26 Oct 1997 12:14:31 -0400

In article <62lpil$qv$4@news1.rmi.net>, drick@hach.com (David L. Rick) wrote:

> In article <344CAE60.2FBD@exp.net>, music@exp.net says...
> >
> >Yesterday someone posted a recommendation that AES/EBU wiring between
> >the in/out of a DAT machine to a digital in/out soundcard be no longer
> >than 5 meters (approx. 16 feet).  What happens if a 20ft cable is used? 
> 
> Nothing bad, provided you're using real 110 ohm digital cable to 
> begin with.  Ordinary mic cable is a bad idea.  For some reason
> it is becoming traditional to make digital cables lurid pink in color,
> but I don't think this has much effect on data integrity.<g>
> 
Well, there are some daredevils (like me) who do funny stuff like find out
what works, ignoring all "expert" advice. The following applies to AES/EBU,
SPDIF is a different story (but using 75ohm coax cable is what should be
done with it, and it can also go for long distances).

In the studio I work at, there are mic lines and tie lines running around.
We had a rush job - make 6 DAT copies of a just-sequenced album master in
Sound Designer for delivery ASAP.

We sent AES-EBU from one studio to two others where there were more DAT
machines, in one long daisy chain. It's hard to calculate the run, which
also went through 5 patchbays, but it must have been at least 150 ft. At
the last device on the receiving end, we listened carefully for ticks and
pops for about 5 minutes. There were none.

This was a real torture test - espcecially because of the bantam patch
points, but it ran successfully over ordinary mic wiring, although we
avoided sending over multi-ended tie lines. If there are no ticks and pops
on the receiving end, then it is fine. Jitter is irrelevant as long as you
are making a tape or HD recording - the jitter issue arises only if you are
converting to analog.

The only reliable advice about AES/EBU is: listen carefully to the
receiving device. Any problem will be readily apparent as very audible
ticks and pops. A bad cable, no matter how short, will cause problems too.
And some devices are better receivers than others.

Thema:	Re: AES/EBU wiring advice?
Von:	shlampen@aol.com (ShLampen)
Datum:	25 Oct 1997 18:23:15 GMT

In article <62lpil$qv$4@news1.rmi.net>, drick@hach.com (David L. Rick) writes:

Where's that Belden guy, now that we need him?  Napping on the job!
>Seriously, you can get suitable stuff from Apogee, Belden, Canare, Gotham,
>and alphabetical others.  Several of these companies have web sites.

HERE I AM!!!!!  Our web page is www.belden.com.  Or just get some Belden
1800A (install) or 1800F (new flexible) AES/EBU. <Please Mr.
Moderator...they ASKED!>

> For some reason
>it is becoming traditional to make digital cables lurid pink in color,
>but I don't think this has much effect on data integrity.<g>

No. It's just that customers complain when the digital cables look like
the analog cable. The BBC says purple means digital. What do you guys say??
 Would love some opinions on this!

Steve Lampen
Technology Development Manager
Belden Wire & Cable Co.
www.belden.com
My new book, "Wire, Cable, and Fiber Optics for Video and Audio Engineers"
has just been published by McGraw-Hill.

Thema:	Re: AES/EBU wiring advice?
Von:	Lorin David <Lorin@SPL-Online.com>
Datum:	Sat, 25 Oct 1997 09:03:06 -0700

music@exp.net wrote:
> 
> Yesterday someone posted a recommendation that AES/EBU wiring between
> the in/out of a DAT machine to a digital in/out soundcard be no longer
> than 5 meters (approx. 16 feet).  What happens if a 20ft cable is
> used?

The installation manual for the AMS/Neve Audiofile says that S/PDIF
lines should be kept shorter than 1 metre, but that AES/EBU can be run
practically as long as you want.

I've personally had problems with clicks and pops on 15 ft. S/PDIF
lines.  The problems went away when I shortened the lines to 1 metre.  I
have no idea why.  Probably something to do with my environment.

Just anecdotal evidence.

Lorin

Thema:	Re: AES/EBU wiring advice?
Von:	shlampen@aol.com (ShLampen)
Datum:	27 Oct 1997 13:34:18 GMT

In article <3452183A.700C@SPL-Online.com>, Lorin David
<Lorin@SPL-Online.com> writes:

>I've personally had problems with clicks and pops on 15 ft. S/PDIF
>lines.  The problems went away when I shortened the lines to 1 metre.  I
>have no idea why.  Probably something to do with my environment.
>
Clicks and pops certainly sound like bit errors.  Could it be the
difference between 3 volts (AES) and 1 volt (SPDIF).  I can't imagine any
difference except over hundreds of feet.  Was the cable you used real 75
ohm coax? 

Just curious.


Steve Lampen
Technology Development Manager
Belden Wire & Cable Co.
www.belden.com
My new book, "Wire, Cable, and Fiber Optics for Video and Audio Engineers"
has just been published by McGraw-Hill.

Thema:	Re: AES/EBU wiring advice?
Von:	Lorin David <Lorin@SPL-Online.com>
Datum:	Mon, 27 Oct 1997 08:50:22 -0800

ShLampen wrote:
> 
> Clicks and pops certainly sound like bit errors.  Could it be the
> difference between 3 volts (AES) and 1 volt (SPDIF).  I can't imagine
> any difference except over hundreds of feet.  Was the cable you used
> real 75 ohm coax?
> 
> Just curious.

Yup.  Tried both '58 and '59.  The brand that starts with "B." <g>  And
the problem wasn't voltage - S/PDIF out to S/PDIF in, and the problem
went away when I shortened the cables (based on what I read in the
AMS/Neve documentation).

I haven't had that problem with AES/EBU though.  That's what led me to
suspect that the problem may be my environment - perhaps my digi lines
are picking up something out of the air (as opposed to introducing the
problem themselves) and the common mode rejection in the balanced
AES/EBU line filters out whatever is causing the problem.

I still don't know what _caused_ the problem.  All I know is that short
S/PDIF lines solved it.  Go figure.

Lorin

Subject:
AES/EBU to S/PDIF conversion - Is it possibel, what does it involve?
From: rodgold@aztec.co.za (Rodney Gold)
Date: Tue, 26 Aug 1997 13:44:59 GMT
Message-id: <3402d9ff.29908513@ct-news.iafrica.com>

I am running a purely Meridian digital audio system - S/PDIF from a
transport to a 518 digital processor which can accept AES/EBU or
S/PDIF - - I would like to run a Roland digital equaliser between the
2 units - Problem is the Roland only accepts AES/EBU , now I need some
system to convert S/PDIF output of my transport to the AES/EBU of the
Roland digital equaliser.
Any advice- - is this possible - please help- I woul;d really like to
use this roland unit - but am worried about the S/PDIF out of my
transport to the AES/EBU in of the unit.


Rodney Gold

"The nicest thing about smacking your head against the wall is-
 the feeling you get when you stop."


Subject: Re: Problems with AES (New York)
From: louie@u.washington.edu (Gary Louie)
Date: 15 Jan 1997 18:15:43 GMT
Message-ID: <5bj6sf$gak@nntp5.u.washington.edu>

Sean, I am the Secretary for the PNW (Seattle) Section of the AES, and I
can feel for you. Unfortunately, just about everybody who deals with the
NY office has some complaint about effiency. This is regularly heard at
the AES convention business meetings. Your exact complaint is quite
common. 

I am sure the AES office does the best they can, and cannot be compared to
corporate effiency (hmm, is that an oxymoron??). Management is constantly
changing, membership is growing rapidly (especially outside the US), and
AES business is conducted worldwide, with all the problems of
international volunteers, languages, postal, time zones, etc.

I suggest that you be firm but unwavering in following up. Call the office
every week until they come through. Don't rant. Keep all your paperwork
and records handy. Get names of who you speak with. You do have their
toll-free number? 1-800-541-8653  You can also Email them (hq@aes.org).
If you really want to "go to the top", also write a letter to the
Executive Director, Roger Furness. He seems to be a very nice fellow
who has been very concerned with this kind of ineffiency since taking the
position a few years ago. 

I think that if you participate in the activities of the AES, you will
find it worthwhile in the knowledge you gain and the people you meet!



In article <32DACFAE.7C64@top.monad.net>,
Sean  <blue_planet@top.monad.net> wrote:
>I am a recent member of the Audio Engineering Society.
>
>I became a member late in 96 (payed $70 fee for entire year membership)
>and was told that I would receive back issues 
>(issues starting with Dec 96) of the Journal of the AES.
>
>AES staff noted that it may take awhile for me to get these
>back issues as they are mailed differently than regular the
>monthly journal.
>
>Well...its 1997 and I still have not received my 1996
>back issues...I did get July/August 96 thru Nov 96...guess
>Dec 96 is being mailed "differently" as well.
>
>I am sorry to say that the two times I have spoken
>with AES NY staff, I have not been impressed.
>
>I just got my bill for 1997....I guess I will pay
>it and hope that someday I will get my 1996 issues.
>
>Has anyone else had simular experiences?
>
>Anyone have advice per this matter?
>
>Perhaps I am not being patient enough...

-- 
-------------------------------------------------------------------
Gary Louie/Staff Audio Engineer
Univ. of Washington School of Music/Seattle, Washington USA
Internet:louie@u.washington.edu
Subject: Re: Problems with AES (New York)
From: louie@u.washington.edu (Gary Louie)
Date: 15 Jan 1997 18:15:43 GMT
Message-ID: <5bj6sf$gak@nntp5.u.washington.edu>

Sean, I am the Secretary for the PNW (Seattle) Section of the AES, and I
can feel for you. Unfortunately, just about everybody who deals with the
NY office has some complaint about effiency. This is regularly heard at
the AES convention business meetings. Your exact complaint is quite
common. 

I am sure the AES office does the best they can, and cannot be compared to
corporate effiency (hmm, is that an oxymoron??). Management is constantly
changing, membership is growing rapidly (especially outside the US), and
AES business is conducted worldwide, with all the problems of
international volunteers, languages, postal, time zones, etc.

I suggest that you be firm but unwavering in following up. Call the office
every week until they come through. Don't rant. Keep all your paperwork
and records handy. Get names of who you speak with. You do have their
toll-free number? 1-800-541-8653  You can also Email them (hq@aes.org).
If you really want to "go to the top", also write a letter to the
Executive Director, Roger Furness. He seems to be a very nice fellow
who has been very concerned with this kind of ineffiency since taking the
position a few years ago. 

I think that if you participate in the activities of the AES, you will
find it worthwhile in the knowledge you gain and the people you meet!



In article <32DACFAE.7C64@top.monad.net>,
Sean  <blue_planet@top.monad.net> wrote:
>I am a recent member of the Audio Engineering Society.
>
>I became a member late in 96 (payed $70 fee for entire year membership)
>and was told that I would receive back issues 
>(issues starting with Dec 96) of the Journal of the AES.
>
>AES staff noted that it may take awhile for me to get these
>back issues as they are mailed differently than regular the
>monthly journal.
>
>Well...its 1997 and I still have not received my 1996
>back issues...I did get July/August 96 thru Nov 96...guess
>Dec 96 is being mailed "differently" as well.
>
>I am sorry to say that the two times I have spoken
>with AES NY staff, I have not been impressed.
>
>I just got my bill for 1997....I guess I will pay
>it and hope that someday I will get my 1996 issues.
>
>Has anyone else had simular experiences?
>
>Anyone have advice per this matter?
>
>Perhaps I am not being patient enough...

-- 
-------------------------------------------------------------------
Gary Louie/Staff Audio Engineer
Univ. of Washington School of Music/Seattle, Washington USA
Internet:louie@u.washington.edu
