Hi, On Wednesday 14 April 2004 09.47, Anders Torger wrote: > On Tuesday 13 April 2004 19.17, Anders Torger wrote: > > Is there any work done for transporting digital audio over ethernet? > > For example a library, an open standard or something? > > > > /Anders Torger > > Thanks for the replies. However, I should have specified in more detail > what I am after, I mean something like cobranet, but without the need > for special hardware. > > I'm thinking about trying to transfer digital audio over ethernet, with > the goal of being able to build a convolver cluster. The idea is to > have one computer with say a 24 channel sound card, and to that connect > a set of other computers through ethernet (100 megabit or gigabit > depending on requirements). > > The inputs taken from the sound card is broadcasted on the ethernet so > all other computers in the cluster get the inputs, and they send their > convolved outputs back to the sound card computer, whose only task is > to mix together the result, and put it to the sound card outputs. > > One application when this type of design would be suitable is WFS (Wave > Front Synthesis), with moving sources in simulated reverb, something > which is extremely demanding (one 3 GHz Pentium 4 can handle only one > source for a 24 channel system). > > Say if you build such a system with 10 cluster nodes plus the sound card > machine, you could render 10 dynamic WFS sources, but would have to > distribute 10 channels from the sound card machine, and get back 10 * > 24, which would be ~20 megabits/s broadcasted from the sound card > machine to the cluster nodes, and ~400 megabits/s back. One channel is > 48 kHz 32 bit floating point, that is ~1.5 megabit/s. > > Thus, I think it is necessary to implement something operating on the > ethernet level to get best performance in terms of throughput and > latency.
I think Bob Ham (he's probably here somewhere) was some time ago working on an audio over ethernet layer. As I recall he was later convinced that firewire would be an easier, more reliable, solution. Now that firewire cards are quite cheap this might very well be true. I wonder if it's easy to connect this many nodes with firewire? /Robert
