Equipment Optimization Questions

[Boomzilla]

I'm engaged in rearranging at Casa Boom this evening. And before the inevitable "what's the best way to arrange this" decisions, I thought I'd throw a few questions out for you guys:

1. My primary video route is from the coaxial cable feed directly to a cable box, and from there (via HDMI) through an AVR and on to the TV. The cable box, the television, and the AVR all have Ethernet connections, but those connections are not normally used (that I know of) except for firmware updates. Is there any potential harm to my audio from having the Ethernet feeds to these items run through the same switch that I'm routing my audio through?

2. There is an Apple Airport Express in the listening room, also connected via Ethernet that serves as my WiFi for the iPad (that controls Roon). The Express is currently located immediately behind the equipment rack, and in close proximity to both the (mostly unshielded) power cords and the system's interconnects. Could RF interference from the Express affect the audio components? If so, how far should the Express be moved away from the wiring to avoid this? Also, could there be any negative impact on the audio from having this Airport Express Ethernet cable run through the same switch as the audio?

3. With the equipment rack offset from the center of the speakers, I'll probably end up with one speaker wire (and one subwoofer lead) shorter than the other. Will this make any difference (that might have to be compensated for via the balance control)? I wouldn't think so, but thought I'd ask for confirmation.

4. Several items will have wall warts & DC power supplies. These will (off the top of my head) include at least the Ethernet switch and the Microrendu. The DC wiring appears to be unshielded. How far away from power cords and interconnects should the DC wiring be to avoid interference?

5. How long can a 4K HDMI cable be without problems? I know that "as short as possible" is the desired answer, but with the equipment rack offset from the TV screen, some accommodation may be needed.

6. For efficiency and appearance, I plan to bundle cables in groups (AC power, interconnects, DC feeds). In which of these bundles do Ethernet and HDMI cables belong?

7. In many cases, unless I make or have made custom length power cords and interconnects, there will be excess cabling to be dealt with. I know that it's better to deal with folded bundles than larger loops, but should those folded bundles be in closest proximity to the source or destination component?

8. The shelves I'll be using are open on all four sides, and the wall behind will be white. Most cabling is black. To avoid an eyesore, what's the best way to "hide" the cables between vertical shelves without having to run them to the edges of the rack? I was thinking that a black curtain on the back of the rack could easily be moved out of the way to change wiring, but would make the cabling less noticeable. Any other good ideas?

9. If I do need to isolate some of the Ethernet lines from others, can I simply daisy-chain multiple switches, or should I use multiple routers instead for additional isolation? Router / switch combination? Arranged how?

These are (for the most part) simple questions, but before I expend the effort to make optimization changes, I might as well get this right...

Thanks - Boomzilla

[creimes]

Keep power away from everything else as much as possible, that's one thing I try my best at behind my rack.

Chad

[Ex_Vintage]

I'll chime in where some experience exists:
3). Wire length will not matter unless it is way undersized with respect to gauge. You would have to get to >100ft with something less than 12ga to be even remotely concerned.
4). As previoulsy stated, keep analog and digital signal away from low voltage DC and away from 120V AC lines. 1ft minimum. Parallel runs together (of the groups) are bad.
5). I am running 4K HDMI 30 ft with no problems.
6). If you are going to "bundle AC power cables. Don't loop them in a circle. Loop them in a figure 8 fashion.
7). Loops as close to the power source, not the load equipment.

[Boomzilla]

It took me about three hours just to assemble the new shelving and move the components. Although functional, they still have rats-nest wiring behind them. I predict it'll take another two to three hours to organize and sort the wiring, and I'll need to shorten a LOT of it to make it fit without excess. Lighter components such as the power strips, Ethernet switch, Airport Express, etc. are light enough that they won't sit neatly on the rack, but are skewed by the tension or weight of the wires they're connected to. I'm considering using iron weights to anchor them in their places. A 5# weight should suffice to hold the Ethernet switch, for instance. The Power strips can't be weighted due to the wires on top, and may need to be Velcro'd in place. Ditto with the Airport Express... Being neat is a LOT of work!

Another problem is how to deal with stereo and movie sound. If I want to use the (higher quality) stereo DACs and amplifiers for stereo listening, then I need to have two pairs of subwoofer interconnects, two pairs of speaker wires, and parallel Ethernet and interconnect wiring. The AVR is unbalanced, the stereo gear balanced, causing even MORE interconnects to be needed.

And the next time that a component shows up for review, all the wiring gets torn apart again.

I'm thinking that the rat's nest may be inevitable. I'll just need to sort it on about an "every two or three month" basis to remove unused and temporary cabling.

Boomzilla

PS: Factors that would simplify the system at the cost of some functionality:

1. Eliminate the subwoofers and go to full-range speakers
2. Decide once and for all on "center channel or no." Then either use the AVR or the stereo-only setup exclusively.
3. Accept the premise that some compromise IS necessary

[DYohn]

1) no
2) no
3) no
4) It doesn't matter
5) 50 feet
6) it doesn't matter, but if you plan to do serious cable management it's probably good to make them their own bundle
7) it doesn't matter
8) whatever gets you through the night
9) I don't know what you are talking about

[Boomzilla]

Thanks, DYohn - If number 1 is a "no," then number 9 is moot.

[geeqner]

Can't answer them ALL - but have a few simple points to add:

One Digital Audio (or whatever) crossing another digital (LAN/WAN/Ethernet) should be "NO Biggie" - the Zeroes and Ones should not interfere with eachother.
(But keep 'em away from any sensitive Low-Level Audio.)  They are unlikely to interfere with other digital connections / cables - but digital CAN induce interference in unshielded analog wiring. 

(In most high-rise building, when it's quiet, most Fire Alarm Speakers will quack like a duck faintly from the digital polling lines being picked-up by the 25 or 70-Volt Audio Circuits feeding the speakers.  This is a different scenario from the wiring within your Sound System Cabinet / Rack, but it does illustrate a point / possibilities.)

As for Power Cables - I like the Outlet Strips with the slots on the back. I run a piece of wood or metal across the back or use the rear edge of a shelf, insert screws, and "hang-up" the Outlet Strip. Then, I can use twist-ties or velcro-straps to bundle the power cords and keep them off the floor / away from other stuff. I also like heavy-duty Outlet Strips that have the main cord with a plug that lays flat against the wall = takes-up less space / less chance of "kinking-over" if other stuff gets jammed up against it.  Some Outlet Strips have sockets that can be rotated 90-degrees or have wider spacing for some of them in order to accommodate the "wall-worts".  This also suspends them off the back and gets them out of the way.