AES/EBU option for home studio setup.

[Redliner]

I have a pair of Genelec 8320A monitors and I am just about to add the 8350A Subwoofer. I have the SAM calibration kit and the Genelec software installed.

I'm currently running a MOTU 624 https://motu.com/products/avb/624 I've had for a 4 years. Unfortunately the 624 does not have AES/EBU output which would allow me to connect digitally to the Subwoofer. The Motu 624 has TOSLINK optical out, and the Subwoofer only has AES/EBU.

I have been researching and concluded I have a few of options.

1. Buy a new interface to replace the Motu 624 that has the AES outputs. But also has audio input. Such as a RME UCX
2. Buy a converter such as the HOSA ODL-312 which will convert the TOSLINK output of the MOUT 624 to a EAS/EBU XLR
3. Buy a USB digital interface that will output AES directly, so a direct link between computer and Subwoofer.

Option 1 is a bit too expensive and will make my MOTU 624 redundant.
Option 2 requires the signal to pass through the Motu on onto the Sub via a converter.
Option 3 would allow me to have a parallel signal chain, I could keep the Motu connected as well and use it for its inputs (although i never use them). But this is also a more expensive option than Option 2.

The thing that I need your wisdom on is... does passing the signal through the Motu and then the TOLNK to AES converter mean the signal/sound will be worse off than Option 3?? I'm still unlcear where the AD conversion will take place.

any help greatly appreciated.
Red

 

[antcollinet]

I have a pair of Genelec 8320A monitors and I am just about to add the 8350A Subwoofer. I have the SAM calibration kit and the Genelec software installed.

I'm currently running a MOTU 624 https://motu.com/products/avb/624 I've had for a 4 years. Unfortunately the 624 does not have AES/EBU output which would allow me to connect digitally to the Subwoofer. The Motu 624 has TOSLINK optical out, and the Subwoofer only has AES/EBU.

I have been researching and concluded I have a few of options.

1. Buy a new interface to replace the Motu 624 that has the AES outputs. But also has audio input. Such as a RME UCX
2. Buy a converter such as the HOSA ODL-312 which will convert the TOSLINK output of the MOUT 624 to a EAS/EBU XLR
3. Buy a USB digital interface that will output AES directly, so a direct link between computer and Subwoofer.

Option 1 is a bit too expensive and will make my MOTU 624 redundant.
Option 2 requires the signal to pass through the Motu on onto the Sub via a converter.
Option 3 would allow me to have a parallel signal chain, I could keep the Motu connected as well and use it for its inputs (although i never use them). But this is also a more expensive option than Option 2.

The thing that I need your wisdom on is... does passing the signal through the Motu and then the TOLNK to AES converter mean the signal/sound will be worse off than Option 3?? I'm still unlcear where the AD conversion will take place.

any help greatly appreciated.
Red

Welcome to the forum.

What format is the input to the Motu? If digital, then there will be no quality loss from the Toslink to AES etc. To be honest - even if analogue - there will be no audible quality loss. However, it might be worth describing your full set up of source - to (all) speakers. While there will be no quality loss in the conversion you might need to consider differential delays between main speakers, and sub, if the signal path is different. (Or does the genelec sub extract and pass on the signal to the mains?)


PS. I can't find a 8350 sub - do you mean the 7370?


EDIT - having said all that - consider using analogue connection from the motu. With balanced interconnect to the Genelecs you are going to be unable to hear any difference compared to a digital connection.

 

[Bamboszek]

I believe you meant 7350A instead 8350A.

You said that you don't use inputs, but do you need any other outputs or functionality apart from digital out? Headphone, line outs, ASIO drivers, etc?

SMSL PO100 with RCA to XLR digital cable would be probably the cheapest and the simplest way to connect 7350A to PC.

 

[Redliner]

Welcome to the forum.

What format is the input to the Motu? If digital, then there will be no quality loss from the Toslink to AES etc. To be honest - even if analogue - there will be no audible quality loss. However, it might be worth describing your full set up of source - to (all) speakers. While there will be no quality loss in the conversion you might need to consider differential delays between main speakers, and sub, if the signal path is different. (Or does the genelec sub extract and pass on the signal to the mains?)


PS. I can't find a 8350 sub - do you mean the 7370?

Thank you for the welcome. I'm new to this issue so thought I would ask the experts. While researching the options this forum popped up quite a lot.
the MOTU connects via Thunderbolt, it has TRS outs and TOSLINK digital out. Once the Sub has the digital input it is connected to the other monitors also with AES.

You mentioned there will be no loss in using a TOSLINK to AES converter like this?

 

[antcollinet]

Sorry yes 7350A
MOTU connects to computer via USB. Once the Sub has the digital input it is connected to the other monitors with AES.

My edit in advice (from my point of view) stands. Start with a balanced analogue connection from the Motu to the sub.

Once you have used that for a while, and gotten used to how is sounds - try introducing the Toslink to AES converter. Listen to it during the return window. When you realise it doesn't really sound any different )) then you can return it.

 

[antcollinet]

You mentioned there will be no loss in using a TOSLINK to AES converter like this?

Correct. It will most likely be bit perfect conversion. Even if it were not, any conversion artefacts will be well below the threshold of human hearing (assuming the design is implemented correctly)

 

[Redliner]

My edit in advice (from my point of view) stands. Start with a balanced analogue connection from the Motu to the sub.

Once you have used that for a while, and gotten used to how is sounds - try introducing the Toslink to AES converter. Listen to it during the return window. When you realise it doesn't really sound any different )) then you can return it.

I barked up many a wrong tree before, it appears I am doing it again.

 

[sergeauckland]

Just for information, AES-EBU and S-PDIF have identical data. The only difference is that some of the status bits indicate 'Pro' on the AES-EBU and 'Consumer' on the S-PDIF, although there are many exceptions, and very few decoders take any notice of those status bits.

AES-EBU is usually 110 ohm balanced whilst S-PDIF is 75 ohm unbalanced, but that is only if concern with very long cable runs, of the order of hundreds of metres, not for domestic lengths. Furthermore, there is a 75 ohm standard for AES-EBU which differs from S-PDIF only in the status bits as mentioned above. and in the voltage levels, which are higher for AES-EBU. Note that S-PDIF receivers and decoders will accept 75 ohm AES-EBU perfectly happily.

The reason for 75 ohm AES-EBU is that in combined Audio/video facilities, AES-EBU can use existing 75 ohm video cabling so saving on cabling costs. It has nothing to do with audio performance. Incidentally, AV facilities are often cabled with 110 ohm balanced cable as analogue audio is perfectly happy with 'digital' cables. Cable costs are important in overall studio costs.

S.

 

[LTig]

... and as the sensitivity of the AES/EBU input is 200 mV (see here on page 15) it is possible that the output voltage of a COAX SPDIF output (0.5V, divided by about 2) of a cheap TOSLINK/Coax converter without any electrical adaptation is sufficient.

This Rane note is a good read:

https://www.nu9n.com/images/AES3-SPDIF-notes.pdf

 

[Zetti]

I believe you meant 7350A instead 8350A.

You said that you don't use inputs, but do you need any other outputs or functionality apart from digital out? Headphone, line outs, ASIO drivers, etc?

SMSL PO100 with RCA to XLR digital cable would be probably the cheapest and the simplest way to connect 7350A to PC.

I am using this SMSL interface with ANALOG cables (1m and 1.5m cables) and everything seems fine. I was on a purist AES quest but just gave up.

 

[LTig]

When I replaced the analog XLR cables from my RME ADI2 PRO fs to the Neumann KH750DSP by a 75 Ohm SPDIF Coax RCA cable I noticed no change in sound at all. I stayed with SPDIF because of 1 cable less, and can use the XLR cables elsewhere.

 

[Kyle_PL]

I have a pair of Genelec 8320A monitors and I am just about to add the 8350A Subwoofer. I have the SAM calibration kit and the Genelec software installed.

Genelec 8320A don't have AES/EBU input.
AES/EBU input have Genelec 8330 and higher.

PS. I can't find a 8350 sub - do you mean the 7370?

I think He was thinking about Genelec 7350A