Yeah 12 days really, yes brand new. Which BJC cables? 6 or 6a? They need dispatching from US to the UK so may not arrive in time. I got a good deal on the vodka which is why I went for it. Will see how it is after a few days, definitely harsh on first impression…
Thanks for the advise 
I’ve been having a look at these online and as far as I can gather they are supplied with their own small external power supplies. Is that correct?
MTIA
Well I still have my old Netgear GS105 and Friwo psu, so I popped that in between the router and Cisco and it’s a definite improvement leaving the Cisco just for the hi-fi.
No I don’t believe they are provided with a powersupply, you need to purchase one as appropriate, and Cisco provide such a PSU suitable for devices like PD switches, WAPs and IP phones.
I purchased my 48VDC 300mA PSU separately.
To be fair Tiberio, you keep mentioning your Linn DSM but somehow refuse to answer whether it’s a Klimax, Akurate or Magik. Without knowing that, how can we put things into context.
@Simon-in-Suffolk,…Is it an original external Cisco PSU that you have.?
Is it the only thing that separates a Cisco WS-C2960-8TC-L,.against a 2960 PD,that the powersupply is external.?
If that’s the case,.can’t you just pick out the 2960 powersupply (see picture),.and mount it in its own box with a longer cable to the switch-box.
/Peder🙂
FR, I have been using the switches for about 6 months. My system still ‘PRAT’ as usual and now with more transperancy.
I have a 2960PD on the way. My plan is to power it from an ethernet cable from my 2960 that has poE out. Will be interesting to see if better than a switch that’s plugged into AC. To me the whole reason behind a PD switch is to get it away from the mains entirely, not power it by an external adapter. After this, though, my ethernet/switch adventures will be over.
• This above,.we also had the same idea of,as Darkebear.
To easily explain how we connected these two Cisco’s,.in order to get this soundquality enhancement.
And,.if understand it correctly,has @Darkebear connected it in the same way.
The difference is that he has a longer cable,.between the router and the first Cisco.
We had a Entreq-cable 3m,.from Router to Cisco1 during the whole listening test…See picture 1.
We were running out of space,.so the first switch (Cisco1),had to stand on my Cableoholic-friend’s box for the passive filters to his speakers (I know,not optimally).
Ps: Some might be surprised when you see a standard powercable in Cisco1,.especially when we are in Mr. Cableoholic’s home 
.
But we thought we’re should making it easy 
.
Between Cisco1 and Cisco 2 we exchanged between these cables…See picture 2 (they are described earlier in the thread).
Between Cisco 2 and Streamer,.we had a AQ Diamond 1,5m during the entire listening-test.
Nothing else,.was connected to any of these Cisco’s,when we got this sound-result as described above.
I suspect the secret to this soundquality enhancement is,.that we have two like Cisco quality-switches.
@Xanthe and @frenchrooster,.got a much worse result.
But they had a cheap Netgear,.as the first switch.
/Peder🙂
Hi dear technical cable and switch friends (and not only!) Try Melco cable category 7 and you will see that I sound warm!
Thanks Simon. If I have understood you correctly, you found that it is likely that frame timing variability causes additional processor load during network decoding within the streamer, coping with this load causes electrical noise from the processor that in turn generates errors at the DAC stage and possibly (to a lesser extent) even within the data before the DAC stage.
@Peder this means tests of switches and cables could be sensitive to whether there is streaming data network activity at the streamer NIC (as opposed to listening to a fully buffered track with minimal traffic at the NIC) while you are listening. You may also get a different level of variability in these tests depending on whether you republish the stream locally or are listening from local storage vs. an internet source. You might even be able to remove the cable while listening to a fully-buffered track to test the difference, which would help distinguish between data processing issues and cable antenna noise issues. I think I’ve seen that suggestion from Simon before (apologies if not!).
Thanks,
Chris.
I will probably go for a PSU and if things go well maybe get one built for me by Sean at Custom HiFi Cables.
I’m pretty ignorant about the science here. After Simon has explained things eighteen times, I sometimes start to get ut. Even frame timing will eventually sink in. Maybe.
However, on the matter of using PoE I’m an ignoramus. That said my “hunch” (insert more provisos) is that things will be quieter for the signals if the Ethernet cables are not carrying power and the switch is automatically disengaging those circuits.
[Puts on crash helmet and awaits incoming]
Thanks Simon. And if I recall correctly, you also advise the newer C versions if one has shorter cable runs. Is that right?
Also, do you think I’m barking up the wrong tree in my post immediately above?
Many thanks for your help and patience
Hi, I can’t see that the inter frame timing variances would cause any greater load, but I have found the more consistent the inter frame timing in the transfer bursts the better the SQ. i noted this on the legacy streamers, but not or very marginal in the recent streamers with the new transport architecture. I shared my findings with Naim at the time whilst they were developing the new transports.
I suspect it’s the frequency components created in the noise spectrum caused by the timing of the processing of the frames as they arrive that is causing the effects on SQ.
I found this likely correlation by assessing timed frame traces using Wireshark analysis after having randomly assessed media from different servers with different frame timing characteristics and assessing SQ preference.
Hi, when I looked into it further it only made a difference, from memory, between cable lengths of under or over 50 metres or thereabouts (30 metres at 10Gbps) and one has to actively enable the feature, called Short Reach Mode whilst at the same time disabling EEE.
The current models I believe support these features.
Hey that’s a test I’m really interested in hearing the results of.
Thanks for taking th trouble to do that Charles.
Cheers
Jim
The other factor that none of these cable & switch tests are considering is cable screen grounding;
Do the testers consider this ? or maybe more to the point is do they actually know about it & the potential consequences
I asked the question a few days ago, but no one responded.
Did you have all STP ethernet cables connecting the 2x Cisco shrouded ports & the same to the streamer & NAS, that raises the question is how many earth (ground) points did you have on the network.
I bought 2 BJC 6a in September iirc and happened to get very good clear clean transparent sounding results in my system, replacing really cheap cables.
quite a few others around here got good results with the 6a.
But there is a screening issue that MikeB raises that interacts with your system, plus many other factors that mean it’s impossible to say in advance which might be best in your system.
They charged me about 15 squid for courier at the end of the purchase process - cables arrived 3 days later.
There is not a screen grounding issue with BJC Cat-6A as their RJ45 plugs are not metal shrouded, its these shrouds that make the screen electrical connection from end to end & between other network components. (see pic showing metal shrounds)
BJC Cat-6A has what they call a passive screen
I am still really struggling to understand these sound differences in the context of a buffer?
