Julf
Facts are our friends
Archimago has written up a pretty good Computer Audio Basics blog entry.
"Computer audio basics"
- Thread starter Julf
- Start date
Tony L
Administrator
Curious as to why he brands Apple Air Play as "non-audiophile"? It isn't high-res, but other than that I don't see why it should be inferior to a SB Touch, Pi or whatever. In fact I briefly tried a SB Touch and LMS against my normal iTunes and Airplay and ditched it within a week or two as I couldn't hear and advantage and the interface was hideous compared to using an iPhone as a remote!
I have an Airport Express optically connected to a Deltec PDM3 DAC, and whilst it doesn't sound as good as playing a CD on the Rega Apollo-R I use as a transport it is presentable enough. These days I mainly use it as a method of accessing iPlayer Radio as it means I can grab any R3 program whenever I want rather than when it is broadcast (just streaming to the AE/DAC from the iPhone or iPad, no computer needed).
I have an Airport Express optically connected to a Deltec PDM3 DAC, and whilst it doesn't sound as good as playing a CD on the Rega Apollo-R I use as a transport it is presentable enough. These days I mainly use it as a method of accessing iPlayer Radio as it means I can grab any R3 program whenever I want rather than when it is broadcast (just streaming to the AE/DAC from the iPhone or iPad, no computer needed).
Maybe because of how the clocks are distributed? As far as I recall, airplay is just another network streaming protocol running over 2.4G wifi with sender-controlled clock to achieve ie. multi-room sync (unlike other streaming protocols). This has high potential for time jitter, especially on a wireless link, if coupled directly to a DAC (which I think these devices are).
(I may be wrong, this is just what I recall when reading about it a while ago, in relation to shairport.)
Tony L
Administrator
AirPlay/the Airport Express are known to be pretty poor jitter-wise, but I don't see why they'd be any worse than any other wi-fi connected device. I've never had any issues getting a DAC to lock to an AE, though I believe some do. I've used a MF V-DAC, Rega DAC, Cambridge 752BD and my current Deltec PDM3 and they all sync fine without dropouts or glitches, but I am in no doubt the CD sounds better (as was the case with the SB Touch).
Jonboi
Because Music Matters
Very interesting read - thanks for linking.
I'm effectively using his 'system 2' computer streaming setup.
I recently changed out my Cat 6 and Cat 5e cables for Cat 6a shielded due a house move and having to get cables of different lengths - router, switches etc are all gigabit.
Probably expectation bias - I didn't do a matched volume/blind/AB test - but switching out the Cat 6 for Cat 6A shielded did seemingly improve the subtle nuance of very fine low level detail re sonic results.
It's only a guess, but if Ethernet cables give out any sort of RFI, then the shielding would help stop this RFI noise being picked up by analogue line level cables running alongside.
I use a wired LAN with WiFi access points, as I find streaming by wire is just more reliable than WiFi (802.11 b/g/n @ 2.4 & 5Ghz), and for movies there is less latency.
I will probably update the Wifi side of it to ac later in the year - but otherwise stick with a wired LAN.
Cheers
I'm effectively using his 'system 2' computer streaming setup.
I recently changed out my Cat 6 and Cat 5e cables for Cat 6a shielded due a house move and having to get cables of different lengths - router, switches etc are all gigabit.
Probably expectation bias - I didn't do a matched volume/blind/AB test - but switching out the Cat 6 for Cat 6A shielded did seemingly improve the subtle nuance of very fine low level detail re sonic results.
It's only a guess, but if Ethernet cables give out any sort of RFI, then the shielding would help stop this RFI noise being picked up by analogue line level cables running alongside.
I use a wired LAN with WiFi access points, as I find streaming by wire is just more reliable than WiFi (802.11 b/g/n @ 2.4 & 5Ghz), and for movies there is less latency.
I will probably update the Wifi side of it to ac later in the year - but otherwise stick with a wired LAN.
Cheers
Julf
Facts are our friends
Possibly - but the RF noise from twisted pairs is pretty minimal. Do you have long runs of (unbalanced) line level audio running next to the ethernet?
zippy
pfm Member
Don't forget the shielding only does its job properly if the whole system is shielded (i.e. sockets, plugs etc as well as the cable)
I'm amazed how many people use shielded cable without considering this.
kennyh
pfm Member
This is a question I was going to ask.
I'm using the Maplins pass through home plugs on the router and to the streamer. I take it the leads supplied are just basic Cat 5.
Are you saying I'd probably be wasting my money upgrading just those 2 leads?
As I say this was something I was going to ask anyway today.
Cheers.
Jonboi
Because Music Matters
Yes, which is why I thought of it as a possible reason for hearing differences - but as i say, it could also easily be expectation bias - our ears and brains are easily fooled.
Cheers
Julf
Facts are our friends
And as a shielded cable connects the grounds/earths of the two devices, it can actually increase noise by creating ground loops in poorly designed equipment.