VoltMan

Hi All, I'm brand new to this forum, and really new to digital audio as I'm still literally coming from a CD player! However this SyncE post really caught my eye as this is a technology used in what I do for a living. I think there are quite a few misconceptions about SyncE, mostly because there are not really a lot of engineers outside of telco or manufacturing that have a need to implement it. More or less in simple terms, SyncE is used for frequency (timing) distribution, as a way to incorporate an asynchronous technology (ethernet) amongst synchronous components (like SDH/SONET) to save money. In other words its a cool way of achieving the reliable and accurate distribution of a timing signal across a far cheaper path (ethernet) that doesn't inherently require it, e.g. replace expensive synchronous backhaul networks with cheap ethernet, but still maintain the timing between the synchronous end points. Since its all about distributing timing the "jitter" part discussed above is important only from the context that it requires device clock cycles remain in sync as the path traverses an ethernet network - in reality this jitter has little to do with the actual end-user data - voice in the case of mobile networks, music in the context mentioned above, but more to do with ensuring the synchronous end points transfer data efficiently. Cisco has a really good write-up on SyncE that, if fully read, might provide useful insight : Synchronous Ethernet: Achieving High-Quality Frequency Distribution in Ethernet NGNs* [Mobile Operators] - Cisco Systems As far as digital audio networks are concerned, I don't think anyone here really has to worry about the synchronisation of their packet switched network - keeping in mind the wired (asynchronous) ethernet adapters on your end devices (either PC or dedicated gear) buffer at many layers (L2,L3,L4 and above), and also of note your switch fabric (e.g. Cisco or Netgear etc.) are very very highly likely to be store and forward switching components. On the other hand there are a lot of cool tools everyone has - readily available on either Windows, Mac, or Linux (or at a CLI level on Cisco, Juniper, etc.) - to ascertain if they are having issues at a network layer that may impact reliable playback. Nice to meet everyone here btw! --Volt