Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[frank kayser]

Hi folks,
I've seen a lot of the chatter on this board of digital snakes - and learned quite a bit i.e., just because it runs over CAT5 cable does not mean it is a standard, routable 100 base t or other TCP/IP protocol.  That was an eye opener, and not all digital snakes are interoperable, or able to interface directly with digital consoles.

That said, I have not seen any discussion on the quality of the A-D converters (or D-A).
That would seem to be a primary concern for a quality signal to the board.  Once digital, I can see the huge benefits for transport over CAT5 - size, weight, continued accuracy over distance, noise, etc.

So, any difference between brands?  Are they all using the same chip?  Are there any that use the TCP/IP protocols?

Really curious,
frank

[Scott Wagner]

Are there any that use the TCP/IP protocols?

Standard Ethernet (ie: TCP/IP or UDP/IP) isn't really suited to streaming anything (audio, video, etc).  Data packets can arrive in any order, and there is no real QoS (Quality of Service) functionality.  There's a good reason that non-IP protocols are in use in the audio world such as AES, Dante, etc.  Can you stream audio over IP?  Sure, it's done all the time, but it's lossy and not suited to production audio.

[Mac Kerr]

Standard Ethernet (ie: TCP/IP or UDP/IP) isn't really suited to streaming anything (audio, video, etc).  Data packets can arrive in any order, and there is no real QoS (Quality of Service) functionality.  There's a good reason that non-IP protocols are in use in the audio world such as AES, Dante, etc.  Can you stream audio over IP?  Sure, it's done all the time, but it's lossy and not suited to production audio.

Huh? Dante is most definitely over IP. It can operate with other data on the same network, although in that case it is recommended to use managed switches so you can use QOS. EtherSound and Cobranet are also over IP. EtherSound is more limited in how it interacts with switches, but can go both ways. Optocore SANE can also operate over mixed networks as can Telos Axia.

Currently I think Dante is the leading audio over IP protocol, although there are undoubtably more Cobranet installations than anything else outside of radio stations where it is mostly Telos.

Mac

[Jerome Malsack]

Being a digital transmission one should not be having a S/N issue.  This would be from the A/D and the preamps in use.  Remember the Peamps at the front will also affect the sound with A/D conversion.   

The other big plus is the fact that more than one mixer can be attached to the same stream.  FOH, Video, Monitor, and other as needed.  When sending down to FOH you can now add in delayed towers like the presidential inauguration.  The length of the wire between components will not change the signal or frequency response the way analog systems will. 

For me the cost is still to high for a weekend warrior. 
I do not have jobs with delayed towers beyond 150 feet.
my line level balanced cable is easily able to handle. 

[TJ (Tom) Cornish]

Hi folks,
I've seen a lot of the chatter on this board of digital snakes - and learned quite a bit i.e., just because it runs over CAT5 cable does not mean it is a standard, routable 100 base t or other TCP/IP protocol.  That was an eye opener, and not all digital snakes are interoperable, or able to interface directly with digital consoles.

That said, I have not seen any discussion on the quality of the A-D converters (or D-A).
That would seem to be a primary concern for a quality signal to the board.  Once digital, I can see the huge benefits for transport over CAT5 - size, weight, continued accuracy over distance, noise, etc.

So, any difference between brands?  Are they all using the same chip?  Are there any that use the TCP/IP protocols?

Really curious,
frank

Standalone digital snakes are a niche thing - you're duplicating effort compared to a modern digital board designed around a digital snake - basically they take a chainsaw and cut off the I/O and put it on the other end of a data cable from the control surface half.  In this circumstance there's still only one A and one D.  With a standalone digital snake and a standalone digital board, you're doing A -> D -> D -> A -> A -> D just to get it into the board, and the reverse to get it back out.

I believe the Midas and Behringer protocol - AES50 is Ethernet layer 1 compatible, but not layer 2 compatible.  A&H's options - both for iLive and the GLD are Ethernet layer 2 compliant, and so can be switched and trunked.  Ethersound is of course ethernet based, but has largely been replaced by Dante, which is layer 2 and layer 3 compliant, but benefits from AVB-aware equipment for routing and QoS.  Cobranet is also ethernet based.

[TJ (Tom) Cornish]

Standard Ethernet (ie: TCP/IP or UDP/IP) isn't really suited to streaming anything (audio, video, etc).  Data packets can arrive in any order, and there is no real QoS (Quality of Service) functionality.  There's a good reason that non-IP protocols are in use in the audio world such as AES, Dante, etc.  Can you stream audio over IP?  Sure, it's done all the time, but it's lossy and not suited to production audio.

As Mac said, this is largely incorrect.  Ethernet networks - especially on gigabit links such as are usually deployed with Dante are perfectly suitable for this, and have extremely low latency.  It's possible for packets to arrive out of order, but this is pretty rare, and would never have a material affect on a purpose-designed digital snake system.

The internet is quite another thing, and definitely has the problems you describe, however that's due to long distances which add latency, and oversubscribed networks.

[Scott Wagner]

I believe the Midas and Behringer protocol - AES50 is Ethernet layer 1 compatible, but not layer 2 compatible.  A&H's options - both for iLive and the GLD are Ethernet layer 2 compliant, and so can be switched and trunked.  Ethersound is of course ethernet based, but has largely been replaced by Dante, which is layer 2 and layer 3 compliant, but benefits from AVB-aware equipment for routing and QoS.  Cobranet is also ethernet based.

I stand corrected, but I will point out that Layer 1 is NOT IP.  It simply means that they can use the same physical cabling (but not co-exist).  Layer 2 is getting there, but is not TCP/IP.  Dante, on the other hand, appears to be the real deal (I haven't had any Dante experience).  How does it fare in a routed environment?

On a side note, the use of the OSI layered network model while common is technically incorrect in the TCP/IP world.  The "layers" between the two models do not line up precisely.

[TJ (Tom) Cornish]

I stand corrected, but I will point out that Layer 1 is NOT IP.  It simply means that they can use the same physical cabling (but not co-exist).  Layer 2 is getting there, but is not TCP/IP.  Dante, on the other hand, appears to be the real deal (I haven't had any Dante experience).  How does it fare in a routed environment?

On a side note, the use of the OSI layered network model while common is technically incorrect in the TCP/IP world.  The "layers" between the two models do not line up precisely.

The ink is still pretty wet on the standards, but here's the wiki page for AVB:
http://en.wikipedia.org/wiki/Audio_Video_Bridging

One of the few AVB compliant switches available:
http://www.bssaudio.com/productpg.php?product_id=72

Cisco is still working on support.  I saw one forum post indicating that the 4500E may be qualified late in 2013.

An Audinate (makers of Dante) paper describing Dante networking:
http://www.aes-media.org/sections/uk/Conf2011/Presentation_PDFs/09%20-%20Kieran%20Walsh%20-%20Dante%20Media%20Networking%20KW.pdf

[TJ (Tom) Cornish]

I stand corrected, but I will point out that Layer 1 is NOT IP.  It simply means that they can use the same physical cabling (but not co-exist).

In the case of AES50, I believe it means that they use standard Ethernet transceivers in their devices and obviously the cabling, and I believe the data will survive a passive hub, but it cannot be switched as it isn't layer-2 compliant.

[frank kayser]

Wow.  Good info to digest.  I apologize for stating two questions instead of focusing on just one.  Mea Culpa.

However I guess I buried my primary question - So in an attempt to get back on track, let me try to restate my query:

I was wondering if there is a difference in the quality of the A-D converters on the various digital snake options, and the A-D converters in the various consoles out there.   

Thanks for your patience (and other great answers)