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Voegelchen
Keep in mind, that 1394 has one simple benefit not mentioned here: There are no ...
kdboyce
As an interesting side note to this article, the entire music score and music ...
Digital audio relies on the features and benefits of IEEE 1394
Morten Lave, CEO of TC Applied Technologies
5/25/2011 9:58 AM EDT
Some companies have proposed using other interconnects in professional audio systems. The options are USB and Ethernet.
Some of the low-end consumer-centric music I/O boxes utilize USB 2.0. But USB has a number of limitations in professional applications. USB 2.0 has a theoretical maximum transfer rate of 480 Mbps. Realistically, USB doesn't come close to that rate even in a simple scenario with a PC linked directly to a single peripheral.
But the media-access scheme and protocol are even bigger roadblocks when it comes to professional audio. USB requires that the host PC control all operations. Were an audio application to move data from an I/O box to a mixer using USB, the host would have to read the data from the I/O box and send it to the mixer.
USB lacks any isochronous or synchronization capabilities. In a music application, the bandwidth wouldn't support multiple I/O boxes or mixers. And even if it could, you couldn't synchronize the recording back in the studio.
What about USB 3.0? Certainly the emerging new flavor is supposed to offer much higher data rates. But not cheaply - there are very expensive modular host interfaces on the market.
It's not even clear at this point that USB 3.0 will follow USB 2.0 into ubiquitous deployment. Handset makers are balking at supporting USB 3.0 because of the inconvenience of the connector.
Also, standard Ethernet is also incapable of serving the professional audio application - even the 1-Gbps flavor. Ethernet lacks the required isochronous ability. The Ethernet community is attempting to address the shortcomings of the network technology in multimedia applications by adding the Ethernet AVB (Audio/Video Bridging) layer. We've yet to see that technology mature. But in any event it will still lack the topological advantages of 1394. Moreover, it will be a significant added expense to support Ethernet in I/O boxes and mixers.
Integrating 1394 in audio products
Design teams working on professional audio products have a number of options in terms of ICs that support 1394. There are numerous general-purpose 1394 ICs on the market. And there are some ICs that specifically target professional audio.
TC Applied Technologies, for example, offers the Dice family of ICs. The Dice Jr product can support as many as 64 channels of audio sampled at 96 kHz. The IC includes a direct interface for A/D and D/A converters and includes a hardware mixer.
Extending 1394 in professional audio
There are compelling reasons that could lead to broader integration of 1394 technology into professional audio products. For example, it might make sense to integrate 1394 interfaces directly into instruments and even microphones. To ensure synchronization capabilities, such a microphone would need to be a slave to another product such as a mixer or I/O box. And the microphone would require an integrated jitter-free clock to support synchronization.
It also makes sense to integrate 1394 into several types of speakers. For example, studio-monitor speakers would be a natural for the interface. This kind of implementation allows music to remain in the digital domain from the initial data conversion right through to the analog conversion that drives the speaker.
Not only are professionals using 1394. Now, the trend among pro-am and amateur musicians is toward the FireWire interface, proven and effective across a wide range of platforms.
About the author:
Morten Lave, a veteran of the IC and music industries, is chief executive of TC Applied Technologies, a division of TC Electronics. He can be reached at MortenL@TCTechnologies.tc.
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frenet
5/25/2011 1:19 PM EDT
IEEE 1394 is being removed from its last nich market, professional audio. I can understand the problem of Mr Lave and his desire to see IEEE1394 being the super champion of professional audio and have TCTechnologies which bet everything on IEEE1394 succeed. But if there is no doubt IEEE1394 is a better technology than USB from a latency point of view and from P2P transfer it's a doomed technology which will not live the next 5 years.
USB3 is there with all its default but it will conquer the professional audio by its ubiquity and cheapness. Present in all new motherboards and chipset it's free for the consumer and the raw transfer speed will compensate for lack of P2P transfer. CPU+GPU processing power is cheap (AMD Fusion processor for example), the fact handset manufacturer will not deploy usb3.0 does not seem an heavyweight argument.
And even ethernet with realtime capacity and AVB should unify on stage all the different bus used (midi/DMX/analog transport).
IEEE1394 is a superior technology as was token ring, it wont prevent it to disappear soon. I hope TCTechnologies is going to do USB and Ethernet products soon.
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Charles Hansen
5/26/2011 5:47 PM EDT
Frenet's comment is on the mark.
The "article" was written by the CEO of a company whose revenue depends heavily on FireWire audio. More of an "advertorial", really...
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kinnar
5/29/2011 2:15 PM EDT
Technically IEEE1394 has got more benefit compared to USB if you compare architecture of both. So even though USB 3.0 is getting standardized still the audio equipment designer are using IEEE1394.
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Bert22306
5/29/2011 5:10 PM EDT
Having lived through the various Ethernet/token ring/100VG LAN wars, not to mention Internet Protocol vs IPX vs ISO, and other contenders like DECnet and SNA, let me say I am skeptical about how IEEE 1394's specific attributes will ensure its longevity. Every scheme has its strong suits, but what history shows time and again is that the winner almost always find a way around its weaknesses. The winner is usually the simplest and cheapest solution, which overpowers the competition by "throwing bandwidth" at the problem. Which it can afford to do thanks to its lower cost. And beyond that, the winner usually finds a way, in its upgrade cycle, to introduce features that were once the sole province of the fancier schemes.
The first two versions of USB might have required the PC bus master to poll any connected device, but USB 3.0 is supposed to permit any connected device to initiate transfers. So the advantage of 1394 peer to peer communications becomes not so unique after all. The original USB might have been restricted to mouse and keyboard connections, but USB 2.0 can reach 480 Mb/s, and 3.0 has a path to at least 5 Gb/s. So honestly, how difficult can it be to establish multiple audio patyhs over such an interconnect?
The initially more "elegant" solutions are certainly not the ones that prove to be the ultimate winners.
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Frank Eory
5/29/2011 7:08 PM EDT
Although the author's company has a financial interest in 1394's continued use in pro audio, his points are still valid. 1394's isochronous capability, peer-to-peer capability, and carrying timing information with the data are huge benefits in a recording studio or in a live sound production environment. USB and Ethernet were historically inadequate to meet the demands of multi-channel pro audio production. That could be overcome with the sheer power of huge bandwidth, but it's difficult to imagine audio engineers abandoning a solution that already works, on the promise that something newer and cheaper has more bandwidth, so don't worry about the protocol limitations.
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Bellhop
6/3/2011 3:29 PM EDT
Betamax was technically superior to VHS. The rest is history.
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kdboyce
6/30/2011 2:40 AM EDT
As an interesting side note to this article, the entire music score and music production for the movie "Avatar" was done on 6 Pro Tools HD hardware and software systems and some Mac computers. The HD interface was PCI Express. Earlier, non "HD" products used Firewire and USB2.0.
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Voegelchen
4/26/2013 4:47 AM EDT
Keep in mind, that 1394 has one simple benefit not mentioned here: There are no switches necessary and you can use it as a bus if you have many devices, like in a studio (mixer, mics, effects,...). USB has the disadvantage only to be a point 2 point connection, ethernet needs switches and switches cost time, see AVB and limited number of 7 hops (endpoints & switches)... also regenerating clock from USB devices isn't that easy if not impossible to reach firewire quality in this point. In the technical point of view, firewire is a better solution than ethernet or USB.
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