Network cabling rules
Posted by: Rob J on 04 November 2015
I am about to install a NAS for backup duties (from HDX). I've searched the forum and found quite a bit of helpful info re this, but have a couple of questions which I hope are not too stupid!
I know that ideally the NAS shouldn't be too close to the system, and that's fine. I have a couple of options for location away from the hi fi, but that does take me into the realms of quite long network cable runs, ie, room to room without going thru walls. Are there any rules, or preferences, on which cables can be longer and which should be shorter, ie.... HDX to switch - switch to router - router to nas etc?. Obviously the HDX to switch (or router) run will need to be long to get the router out of the listening room. Should the router and NAS then be close together to keep at least one cable as short as possible? Perhaps the router shouldn't be near the NAS? Obviously they can't all be short. Or are long network cable lengths not really an operational problem?
I intend to use good quality Cat 6 cable throughout. Any recommendations for a good quality router, or any to avoid, would also be greatly received.
Thanks in advance.
I expect someone will disagree with me, but cat 6 should work ok on lengths up to 100m, so anything you might want to do in your home isn't likely to be a problem. As this is all for backup, I don't think SQ should come into it. Possibly if you were going to stream from the NAS to a Naim streamer, then I would keep that shorter rather than longer, but in doing what you describe ut shouldn't be a problem.
I'm not going to suggest a router except to say that personally I would make all the connections via a switch and connect that back to your router, because the switches built into consumer routers don't all seem to handle discovery and streaming properly and a cheap switch like the Netgear GS105 takes all that away from the router. Having said that, Apple routers seem to have more fans than critics.
best
David
Hi Rob, the only reason NAS should far away is noise & flashing LED's, no other reasons.
Mine lives in a small closed door cabinet together with its UPS & the switch, the IPS wireless hub sits on top. This is in the listening room about 1.5m from the hifi rack & about 2.5m from the nearest listening chair.
No need to be concerned with distances in a home system & no reason to be picky over which leg has the longest Ethernet
Have fun setting it all up & keep us posted on how you do it
If your only using the NAS to back up, why not install it next to the HDX and switch it off after you've performed a backup.
If the NAS is for backup rather than UPnP serving, you should be fine with a longish length of cheap CAT5e cable. A Synology or QNAP NAS with a Western Digital Red drive will do a good job.
If it's difficult to run a cable all the way to your router, don't bother, just link them via a switch instead.
Thanks everyone, that's a great help.... I'm on it!
Rob, the 100 Base T and 1000 Base T Ethernet specs say a single segment cable run has to be supported to 100 metres. If you require longer, then fibre should be used or a repeater such as a switch. Therefore this is good for Cat5e and Cat 6a cable - (Cat 7 is not universally industrially recognised or supported/recommended for Ethernet use)
Therefore you should have plenty of room, and any Ethernet segment cable run can be any length within that 100 metres.
Ok Simon, thanks for that.... I'll be well within the 100m. My longest run will be about 9 or 10m and I was initially thinking that may be too long!
Steady on Simon, you will frighten the horses.
Cat7 might not be an agreed standard, but it's been accepted across the audio & AV world as he best performing cable wrt speed (even tho' it's not required) & for RFI screening.
I can't see how it can ever be accepted as a standard with RJ45 plugs being the limiting factor & ITR the cable mnfts are misleading, but outside that it is here to stay.
It is here, I suspect however it will be effectively obsoleted by a formally recognized cable/connector for Ethernet use.
Simon
Just thinking that if cables can pick up RFI, then longer cables are more likely to do so.
Dave - in a normal domestic environment shielded cables are not really required for long runs. If you are routing the cables past some very electrically noisy equipment then yes it will be of benefit. If you are running many cables close together in a bundle - it will be of benefit. But a single long run cable in a typical home - then minimal, if any benefit
Simon
Am I right to infer that shielded cables aren't likely to have a negative effect either, it just that there's probably no advantage in using them?
Just thinking that if cables can pick up RFI, then longer cables are more likely to do so.
This was my logic too, so on that basis I have ordered shielded cables. I just hope they're not too stiff to form around corners!
Just thinking that if cables can pick up RFI, then longer cables are more likely to do so.
This was my logic too, so on that basis I have ordered shielded cables. I just hope they're not too stiff to form around corners!
Actually that can be another advantage to SSTP and SFTP cables, they are more rigid and so you're less likely to bend them tighter than the minimum bend radius. If you bend Ethernet cables too tightly, their electrical performance suffers.
Just thinking that if cables can pick up RFI, then longer cables are more likely to do so.
This was my logic too, so on that basis I have ordered shielded cables. I just hope they're not too stiff to form around corners!
I've got a couple of Chord C-Stream ethernet cables which are quite stiff. Chord recommend a minimum bend radius of 50mm. Tight kinks can affect the performance of the cable, so bend with care!
Am I right to infer that shielded cables aren't likely to have a negative effect either, it just that there's probably no advantage in using them?
Shouldn't be any issue, but just check you don't have earth loops .. an earth loop might not necessarily stop the cable from working, but may cause other issues, such as reduced data reliability.
Simon
Rob, if you're just going to use the Ethernet and NAS for backup, then you can always try disconnecting it during music replay to see if there's any degradation - the acid test!
I have found ethernet cabling a noise source into my system, and progressively mitigated this by a mix of c-stream and cat6 for the long link, increasing distance of my wifi router from head-end switch (~2m), multiple ferrites, a local system switch with linear supplies. I finally replaced my long link to my system quite inexpensively with 15m of fibre and small media converters, to good effect. Pick-up of wifi signals seemed the culprit, while noise-tolerant Ethernet signalling could ignore this, it did result in fine resolution loss from my DAC.
So adoption of shielded cables seems prudent... I suggest also having an Ethernet back-to-back connector and a small patch cable to be able to isolate the cable's screen connection into your HDX for comparison.
Am I right to infer that shielded cables aren't likely to have a negative effect either, it just that there's probably no advantage in using them?
Shouldn't be any issue, but just check you don't have earth loops .. an earth loop might not necessarily stop the cable from working, but may cause other issues, such as reduced data reliability.
Simon
One thing to look out for when using screened Ethernet is having ONE GROUND (earth) & especially so if your different system components are on different power circuits. The golden rule is ONE ground. Ideally have the renderer (Naim) as the ground safety earth & be sure the NAS is not groundeD, use a UTP isolator or a section of Cat6 UTP. The switch may or not carry through the screen, if does not then is really not worth having screened Ethernet anyhow, but if it does carry the screen connection then it's important to stick to the ONE ground rule. The router is invariably not grounded
Very good points Mike. I wouldn't have thought about the cable screening conspiring against us like that! Thanks.
Bottom line Rob is Cat5e or Cat6 UTP is as good as you need in most domestic situations. The fancy priced stuff is invariably Cat7 as it helps sell the essence of rare viper oils (my opinion) & I dread to think about the grounding situations a lot of people have let themselves into with blind use of some fancy high priced Cat7 that promises all sorts of pie in the sky audio utopia. Keep in mind the data is sent from server (NAS) to the renderer (Naim player) in packets & the player confirmes to the server what it has received it & if it's missing something then the server resends that packet. The data is stored on the renderer buffer ready to be played along with the previous & following packets - in other words the renderer plays from the data stored in the buffer, not from or via the cable or from the server.
And yes I use Cat7 but not the fancy stuff, & its correctly grounded.