Topic: AES/EBU>Spdif MiniMe question

[jazzgtrl4]

Hi, just seeing if this works and who uses this insted of the coax on the MiniMe? im running it into a MT II.. Was out taping this weekend and i have dropouts in one of my recordings like DAT dropouts?? ive heard stories of the MiniMe coax not making a good connection and this could happen.

[OOK]

Hi, just seeing if this works and who uses this insted of the coax on the MiniMe? im running it into a MT II.. Was out taping this weekend and i have dropouts in one of my recordings like DAT dropouts?? ive heard stories of the MiniMe coax not making a good connection and this could happen.

Happened to me when I had one.  I had a xlr to coax cable made and never looked back....I actually regret selling my minime now....

peace OOK

[SmokinJoe]

From an Electrical Engineering standpoint, they are 2 different specs, with different voltages, impedances, etc.  http://www.rane.com/note149.html
So what does this mean?  Maybe something, and maybe nothing.  Some people have made simple XLR to RCA cables, plugged them in and it works.  I think it's mostly a question of how fussy your deck is.

Search around... this has been talked about before, with a particular thread started by -Q-, probably under the cable forum.  No need to review it all again here.

[tgakidis]

Andy, AKA Andyjah, runs his minime with the aes > RCA coax into his r44.  I contacted him yesterday to confirm if his cable is 75 or 110ohm and I am waiting for his reply.

[andyjah]

Andy, AKA Andyjah, runs his minime with the aes > RCA coax into his r44.  I contacted him yesterday to confirm if his cable is 75 or 110ohm and I am waiting for his reply.

75 ohm Ted

[SmokinJoe]

Check out the following.
http://taperssection.com/index.php?topic=7676.0
http://taperssection.com/index.php?topic=130522.0

Most people know that digital/binary data is made up of "ones and zeros".  How does that register across a wire?  As 2 different voltage levels... say perhaps a 1 is represented by 5V across 2 wires, and 0 is represented by 0 volts across those wires.  And that flips back and forth between 0 and 5 volts really fast... literally a million times a second.  We would like to think that it can change state instantaneously from one level to another and it would be a nice perfect square wave, but it's not... it takes time, and that's called "Slew rate" and the type of cable and it's impedance actually does effect it.  It kind of blows my mind that it works at all when you think about it.  The point is that when you are connecting AES transmitter to a SPDIF receiver which work on different levels is may work and it may not.  So don't be surprised if it works today with this Minime, with this cable and this R44,  but it doesn't work tomorrow with a V3, a different cable, and an MT.  And don't be surprised if it works at 16/44, but gets flakey at 24/96.

[jazzgtrl4]

Check out the following.
http://taperssection.com/index.php?topic=7676.0
http://taperssection.com/index.php?topic=130522.0

Most people know that digital/binary data is made up of "ones and zeros".  How does that register across a wire?  As 2 different voltage levels... say perhaps a 1 is represented by 5V across 2 wires, and 0 is represented by 0 volts across those wires.  And that flips back and forth between 0 and 5 volts really fast... literally a million times a second.  We would like to think that it can change state instantaneously from one level to another and it would be a nice perfect square wave, but it's not... it takes time, and that's called "Slew rate" and the type of cable and it's impedance actually does effect it.  It kind of blows my mind that it works at all when you think about it.  The point is that when you are connecting AES transmitter to a SPDIF receiver which work on different levels is may work and it may not.  So don't be surprised if it works today with this Minime, with this cable and this R44,  but it doesn't work tomorrow with a V3, a different cable, and an MT.  And don't be surprised if it works at 16/44, but gets flakey at 24/96.

Smokin Joe, thanks for all the info and the links. I had a short male XLR>RCA here at home and tried it with my minime and MT 2. It worked for a bit, then dropped the signal. The minime AES is 110 i found out from Apogee so do i need a 110 cable and it should work?

[JasonSobel]

ideally, you get a 110 ohm AES cable (with XLR connectors), then you use an impedance transformer to convert 110 ohm to 75 ohm, and then you have a regular  75 ohm RCA to RCA S/PDIF cable.

This is a great impedance transformer, and the one that I use to use with my V3's AES output:
http://www.canare.com/ProductItemDisplay.aspx?productItemID=15

[jazzgtrl4]

ideally, you get a 110 ohm AES cable (with XLR connectors), then you use an impedance transformer to convert 110 ohm to 75 ohm, and then you have a regular  75 ohm RCA to RCA S/PDIF cable.

This is a great impedance transformer, and the one that I use to use with my V3's AES output:
http://www.canare.com/ProductItemDisplay.aspx?productItemID=15

Jason, thanks for the link. looks like that is it. so it has a RCA Spdif end? a few of the ones i saw had BNC connectors

[JasonSobel]

ideally, you get a 110 ohm AES cable (with XLR connectors), then you use an impedance transformer to convert 110 ohm to 75 ohm, and then you have a regular  75 ohm RCA to RCA S/PDIF cable.

This is a great impedance transformer, and the one that I use to use with my V3's AES output:
http://www.canare.com/ProductItemDisplay.aspx?productItemID=15

Jason, thanks for the link. looks like that is it. so it has a RCA Spdif end? a few of the ones i saw had BNC connectors

the one that I have (and have always used) has a BNC connector on the 75 ohm end.  but an adapter (BNC to RCA) from radio shack is very inexpensive (i.e. <$5), locks into place, and almost makes you forget that the Canare transformer is BNC in the first place, because the adapter is always connected.

[jazzgtrl4]

ideally, you get a 110 ohm AES cable (with XLR connectors), then you use an impedance transformer to convert 110 ohm to 75 ohm, and then you have a regular  75 ohm RCA to RCA S/PDIF cable.

This is a great impedance transformer, and the one that I use to use with my V3's AES output:
http://www.canare.com/ProductItemDisplay.aspx?productItemID=15

Jason, thanks for the link. looks like that is it. so it has a RCA Spdif end? a few of the ones i saw had BNC connectors

the one that I have (and have always used) has a BNC connector on the 75 ohm end.  but an adapter (BNC to RCA) from radio shack is very inexpensive (i.e. <$5), locks into place, and almost makes you forget that the Canare transformer is BNC in the first place, because the adapter is always connected.

Got it thanks for the info.