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gsawdy
2008-06-08, 15:51
I am setting up SB3 in several rooms as part of a whole house system. In several of the rooms additional wiring would be extremely dificult to run but I do have a surplus pair of RG6 cable to each room. Yes I should have run extra cat5 when the walls were open but I got cheap at the wrong time--penny wise ,pound foolish! I want to use one RG6 to run 5v DC from a highly regulated power supply in the basement (to the SB3's mounted on the wall.) In the other RG6 cable I want to run 24v DC to the volume/distribution units from a second regulated power supply in the basement. I need to know what the amperage rating would be for the RG6 and I'm not sure where to find this type of information as this isn't what RG6 is designed to do. Maybe I can't use it. I'm thinking I need it to carry at least 4 amps in each case.

Please direct me to another forum, if this is the wrong place to post. Thanks George

iPhone
2008-06-08, 18:09
I am setting up SB3 in several rooms as part of a whole house system. In several of the rooms additional wiring would be extremely dificult to run but I do have a surplus pair of RG6 cable to each room. Yes I should have run extra cat5 when the walls were open but I got cheap at the wrong time--penny wise ,pound foolish! I want to use one RG6 to run 5v DC from a highly regulated power supply in the basement (to the SB3's mounted on the wall.) In the other RG6 cable I want to run 24v DC to the volume/distribution units from a second regulated power supply in the basement. I need to know what the amperage rating would be for the RG6 and I'm not sure where to find this type of information as this isn't what RG6 is designed to do. Maybe I can't use it. I'm thinking I need it to carry at least 4 amps in each case.

Please direct me to another forum, if this is the wrong place to post. Thanks George

Their are about a million variables here. Can you see the jacket on the RG6 to get the cable identifier off of it? Can this be done? It probably can. But I would ask is it the correct application? As an example, what if the power supply want bad? One could easily lose all the SB3s instead of just one. Why waste a nice regulated power supply driving a bunch of extra cable length that doesn't really need to be used? Why create an antenna to pick up all the RFI and EMI in your home and take it right to your source device?

Are there not going to be other wires? Interconnects and speaker cable for the speakers? What is an extra wall wart PS cable when the whole thing is not completely wireless anyway?

In my job we put DC on coax feedline all the time to power tower top receiver pre-amps. The only reason we do this is to get a weak signal down a 1800 foot run of feedline to the receiver. One less cable to worry about and if a 3 inch round copper feedline can't carry 12VDC at 1A 1800 feet nothing can. Also remember all this stuff is outside and without the possibility of burning down ones house if something goes wrong in the walls!

Maybe listing your goal for this project would be a be help? What is the end result you are trying to accomplish?

gsawdy
2008-06-09, 06:54
.....But I would ask is it the correct application? As an example, what if the power supply want bad? One could easily lose all the SB3s instead of just one. Why waste a nice regulated power supply driving a bunch of extra cable length that doesn't really need to be used? Why create an antenna to pick up all the RFI and EMI in your home and take it right to your source device?
........ Also remember all this stuff is outside and without the possibility of burning down ones house if something goes wrong in the walls!

Maybe listing your goal for this project would be a be help? What is the end result you are trying to accomplish?

Thank you for your reply iPhone,
when the house was being built I ran lots of wires for a complete Linn system. At that time I didn't know anything about computers as a source nor Squeezeboxes. Installing a server/squeeze system will save a lot of $$$$, is more versitile, and probably give better sound. Most rooms I can get to from either the basement or the attic but I've got a couple of rooms where the roof/ceiling comes down low on the walls and there is no access to run more wires. I need to install the SB3 on the wall with no visible wiring, so wall warts are a no no.

I appreciate your concern for fire issues. I had planned on installing 2 amp in-line fuses both in the basement and at the SB3. The RFI issue I hadn't thought about and don't know how much weight to attach to it. Your advice here is appreciated. Is there a way to block the rfi?

I realize that coax is not the correct solution. Perhaps a better or safer solution would be to take a single run from the power supply to the attic and then inject it into the 4 unused wires in the CAT5 to feed each SB. I could intercept the CAT5 just before it disappears into the roof-ceiling union.

Oh, I have the regulated power supply and no other use for it. It's an Acopian A series so it is far better than the wall wart.

In Edit: The cable is labelled Coleman 32041 RG6/U Quad Shield 18AGW (It's a funny looking 8, but I think it's an eight.) And the CAT5 is shielded. Should the CAT shield be connected anywhere? or just float?

seanadams
2008-06-09, 09:54
You can't reliably power a device like SB3 that way, because it requires a regulated input and there will be a significant voltage drop on the cable. If you have CAT5 for ethernet, consider using POE. Something like this will work: http://www.voipsupply.com/product_info.php?products_id=1330

For the 24V devices... it might work, but do you really not have an AC plug anywhere nearby?

iPhone
2008-06-09, 09:54
Thank you for your reply iPhone,
when the house was being built I ran lots of wires for a complete Linn system. At that time I didn't know anything about computers as a source nor Squeezeboxes. Installing a server/squeeze system will save a lot of $$$$, is more versitile, and probably give better sound. Most rooms I can get to from either the basement or the attic but I've got a couple of rooms where the roof/ceiling comes down low on the walls and there is no access to run more wires. I need to install the SB3 on the wall with no visible wiring, so wall warts are a no no.

I appreciate your concern for fire issues. I had planned on installing 2 amp in-line fuses both in the basement and at the SB3. The RFI issue I hadn't thought about and don't know how much weight to attach to it. Your advice here is appreciated. Is there a way to block the rfi?

I realize that coax is not the correct solution. Perhaps a better or safer solution would be to take a single run from the power supply to the attic and then inject it into the 4 unused wires in the CAT5 to feed each SB. I could intercept the CAT5 just before it disappears into the roof-ceiling union.

Oh, I have the regulated power supply and no other use for it. It's an Acopian A series so it is far better than the wall wart.

In Edit: The cable is labelled Coleman 32041 RG6/U Quad Shield 18AGW (It's a funny looking 8, but I think it's an eight.) And the CAT5 is shielded. Should the CAT shield be connected anywhere? or just float?

Well it looks like this was a study in time management. The Coax cable can't power more then one Squeezebox. Its maximum current rating is 2.3 amps and just one SB3 is close to maxxing that out. The circuit would have to be a parallel circuit so that the voltage would stay constant at 5VDC and the current would vary with the load. Once the second SB3 was turned on, the current demand would exceed the rating of the Coax. Do not even think about using CAT5 to power even one SB3 (most CAT5 is rated at less the half an Amp). As to your shielding question on the CAT5, it depends on if it is really shielded or not. Fully shielded CAT5 has a metal encased RJ45 plug on each end so the whole cable is grounded to the chassis it is connected to. If the CAT5 does not have these encased RJ45s, it could have a full-length shield cover but it would not be grounded so it would not reject EMI.

One last note, a two-amp fuse in the basement will not work because the current will increase with each SB3 added to the circuit. As an example, if you had wiring able to carry the load for three SB3s in parallel, the fuse at the supply would be a 10-amp fuse and each SB3 would have an inline 2-amp fuse.

Possible solution (involving more work) would be to make separate drops with 16AWG two-conductor wire assuming 50-foot runs. Use an inline fuse in each run at the power supply end and connect all the fused leads to the PS positive terminal and the set the output voltage for about 5.5VDC. At 2 amps for each unit with 50 feet of 16AWG you should end up with about a half-volt line drop. Smaller cheaper wire could be used, but the longer the run the larger the voltage drop. Of course all this is using the theoretical numbers, your mileage WILL vary. Most times it is all right to use the next smaller gauge (larger number)if current handling ability and voltage drop are acceptable.

MuckleEck
2008-06-09, 10:17
A thought has occured to me.

Do you have access to power in the Attic?

Could you install a SBR with a small T-amp (or similar) and in ceiling speakers?

Sound quality may not be as good and stereo definition may go out the window unless the speakers are above your bed!

iPhone
2008-06-09, 11:21
I keep going back to the fact that you are planning to hang this on the wall. That is fine, and you are talking about getting power to the unit. What you are not talking about is all the other required items.

One can not just power an SB3 and hang it on the wall. It has to be wired to Ethernet or talk wirelessly to a network. Next it has to be connected to a HT Receiver/IAmp/Amp or Powered Speakers. The SB3 is not a Sonos and does not have a server or built in amp. So there are going to be other wires or other devices that need power at the SB3 install location.

How are these issues being handled? What are you going to be playing the music over (speakers or powered speakers)?

My neighbor has two things that might apply. In his basement he has cut a hole in his wall and mounted a plasic cut-in box to set an SB3 into. On the other side of the wall is a utility closet that has his server, wireless router, a Denon Receiver, and the wires coming from the four (2 Thiel PowerPlane 2.1 in-wall and 2 HighPlane 1.2 ceiling) Speakers. This is a very neat install. Only power and stereo RCAs come into the back of the cut-in box. Upstairs he has a very large Atomic Wall clock what only uses a wall wart (no battery option). He put a power strip in his attic, drilled a hole to drop the DC lead off the wall wart down the inside of the wall to a hole through the wall powering the clock. Something like this might work.

In my home, I installed a chandilier lift. The power was already there for the light, but I needed a power source to run the lift. It voids the warranty if I borrow the power from the light circuit. So I found a 15 amp circuit for wall outlets and extended the circuit with Romex and installed a metal junction box to code with an outlet.

If there is room above the ceiling where you want to install the SB3 on the wall, you might be able to do the same thing. Extend the AC with an outlet, plug the wall wart into the new outlet and drop the DC pigtail of the wall wart down inside the wall.

lanierb
2008-06-09, 14:36
Why not just have an electrician install a recessed horizontal AC outlet and mount the SB3 over top of it on the wall much like people do with plasma TVs? The outlet is still smaller than the SB3 footprint and the SB3 would be flush to the wall hiding the outlet. I bet it could be done fairly easily as long as there is AC somewhere in the vicinity.

(The obvious alternative going through everyone's mind is to just place the SB3 on a table somewhere near an existing outlet but I assume you have good reasons for having ruled that out.)

gsawdy
2008-06-10, 08:03
[QUOTE=seanadams;310176]You can't reliably power a device like SB3 that way, because it requires a regulated input and there will be a significant voltage drop on the cable. If you have CAT5 for ethernet, consider using POE. Something like this will work: http://www.voipsupply.com/product_info.php?products_id=1330
/QUOTE]

Hi Sean, Thank you for the reply. Actually I thought I was using POE, just DIY by intecepting the the CAT 5 and using the last 10 feet or so to send the power to the SB3. Do you know if the Linksys device is passive--I assumed so but perhaps it isn't???? The Acopian power supplies are very tightly regulated. Here are the specs:

NominalOutput 5v
Voltage Adjust+/-V 0.5
Output Current Amps. 6
Regulation: load 0.005%, line 0.005%
Ripple mV RMS 0.25
Model A5MT600

http://www.acopian.com/store/9-(7).aspx?min=1.5&max=5

I can wire it so that there are exactly 5v at the point where I feed the CAT5 which will take care of any voltage losses from the basement to that point.

Now if your POE device is active then my plans won't work and I would need to purchase them but how do they prevent voltage loss and still deliver a regulated output?

Thank you for your insights,
George

gsawdy
2008-06-10, 08:58
I keep going back to the fact that you are planning to hang this on the wall. That is fine, and you are talking about getting power to the unit. What you are not talking about is all the other required items.

One can not just power an SB3 and hang it on the wall. It has to be wired to Ethernet or talk wirelessly to a network. Next it has to be connected to a HT Receiver/IAmp/Amp or Powered Speakers. The SB3 is not a Sonos and does not have a server or built in amp. So there are going to be other wires or other devices that need power at the SB3 install location.

How are these issues being handled? What are you going to be playing the music over (speakers or powered speakers)?


Hi iPhone, et.al.
First thanks for your interest and suggestions. I currently have a SB3 and Audioengine A5 so I have some sense of what I've got to hook up. VBG
I considered putting 120v AC outlets in the attic and plugging in the wall warts there. Didn't seem very safe to me? Maybe a GFI outlet would solve that problem and maybe it's not really a problem. I just like to have electronic things were I can see them and smell them (if they are frying.)

As to how it is all suppose to work.... this will go on a bit but it may be of interest to some so I'll try to provide some links that can be followed up. There is a multi room system/standard that is called ABUS. numerous manufacturers provide devices that fit into this standard: Russound, On-Q, Integra and channel vision that I know of. The basic system consists of a Source and Powered volume controls. Each source requires 24vDC and accepts one analogue input. This signal as I understand it is amplified and distributed to (upto) 4 powered volume controls. Each powered vol control has 2x7.5watt class d amps in it. Manufactures do ot publish spec on these amps which I suspect says all we need to know---voice only at modest listening levels in smallis rooms and then only with efficient speakers. You can get the basic idea of the system by reading this page and following the links to better descriptions of the parts:
http://www.smarthome.com/833X.html
(This is for the discontinued Sonance ABUS system, but is a convenient site to navigate and see all the parts.)

There are two variations on the basic powered vol control. The first is a vol control that sports 20w/c amps (Like the discontinued Sonance units and still available from On-Q under their LyriQ label). The second is right and left line outs for powering an external amp (or for a subwoofer). Many but not all of the 7.5w/c also offer line outs and IR control. A tech at On-q told me the specs for the 20 w/c units are 20-20K +-1db. Here is the link to that unit:
http://www.onqlegrand.com/products/AU1000

What I'm planing is to run the audio cables from the SB3 to the ABUS source unit on the wall behind the SB3 or a nearby closet then the CAT5 signal distributoion to the powered vol control at a convenient spot and then the line outs to wherever the powered speakers will be. I'll also use some ALC (auto line selectors) to allow a TV or iPOD to be plugged in. Although one source unit could fed upto 4 rooms, I'll just use each independently in a room except in the master bed where I'll try out the 7.5 w/c to drive a single ceiling speaker.

HOpe this helps you understand what's going on,

And I'm all ears for any suggestions, especially about wallwarts in the attic where it gets hot in the summer,
George

seanadams
2008-06-10, 09:15
Hi Sean, Thank you for the reply. Actually I thought I was using POE, just DIY by intecepting the the CAT 5 and using the last 10 feet or so to send the power to the SB3.

No that's not proper POE. POE devices (802.3af) send a high voltage from the switch which is then regulated at the point load.

http://en.wikipedia.org/wiki/Power_over_Ethernet


Do you know if the Linksys device is passive--I assumed so but perhaps it isn't????

It's not passive, it's essentially a DC->DC power supply.


The Acopian power supplies are very tightly regulated.

It doesn't matter. You will not have a regulated supply any more if you put a big resistor (eg long cable) between the power supply and the device. You could easily lose one volt, which would be enough for SB3 to not operate.


I can wire it so that there are exactly 5v at the point where I feed the CAT5 which will take care of any voltage losses from the basement to that point.

Actually you can't. The voltage drop is dependent on the power being drawn at a given instant, so it's not even a fixed voltage that you end up with.


Now if your POE device is active then my plans won't work and I would need to purchase them but how do they prevent voltage loss and still deliver a regulated output?

Because the regulator is placed at the point of load. You will get 5V output regardless of load or cable length. It doesn't matter if the cable delivers 10V or 43.8V, the output is always 5V.

seanadams
2008-06-10, 09:23
I just noticed that you said you're only going 10 feet. In that case you should be fine sending 5VDC across it. I had assumed it was a longer distance. Here's a calculator you can use to estimate the voltage drop:

http://www.demarctech.com/techsupport/poecalculate.htm

If you can stay in the range of 4.8 to 5.0V (measured at the point of load, with the load powered) you should be OK.

gsawdy
2008-06-10, 09:50
Thank you Sean, I'm going to bookmark that site. I can crank up the output of the supply a little too.
George