1 PC, 2 Rooms, 2 Receivers

pom134

Distinguished
Nov 28, 2010
3
0
18,510
I didn't know where to put this and since the sound portion is what started this all I decided to put it in HT. let me know if there is a better place. This is what I want to do:

I want to have one PC with all my music on it. I want to have a monitor on that PC and my amp/speakers on that computer in one room.

In an adjacent room I want a second receiver and speakers hooked up to the same computer and also a touchscreen monitor on the wall that is a duplicate of the screen in the first room.

The idea is that I want to be able to control my music from both rooms and have it play in both room at the same time. The touchscreen on the wall is just kind of cool and makes it so I don't need a mouse around to dig through stuff.

I drew a simple picture if my description above is no good.

8hTfr.jpg


My issue is that I don't know how to extend a video signal 30+ feet or for that matter what the best way to extend an audio signal that far is or the USB signal for the touch screen.

If we want to start easy, what is the best way to send an audio signal that far to let me control the speakers in both rooms from the PC in one room?

SOrry if this is confusing, thanks for any help!
 

anwaypasible

Distinguished
Oct 15, 2007
718
0
19,010
they make component cables 30+ foot.
if you want usb cables, you need the 'active repeater' type of cables.. they are more than a usb cable, as you will find a large block on the end.
i dont know how touchscreens connect to a computer at all.. maybe a combination of video cords and a usb cord?

anyways.. if you want to split a signal with a long run of cable, it is usually best to use an amplifier to bring the voltages back up.
when you split the signal, you drop the voltage to half.
and when you add long runs of cable, the voltage drops even more.
that is why they have 'distribution amplifiers' on the market.

an example of such a distribution amplifier can be seen here:
http://www.cablestogo.com/product.asp?cat_id=3119&sku=41065#

i really dont know who makes the junk ones and who makes the high quality ones.
the website may or may not be the best product available, but i passed along the link to give you an example of the design.. to show you that the product exists.

again, if you need a USB cord 30+ feet .. those active repeater cables usually come in lengths of 15ft each.
if i remember correctly, you can connect like three or four of 'em together.

getting both receivers to play audio at the same time from the s/pdif output isnt heard of.
i dont know if it can be done with custom work, but that is something that would require packet sniffing of the data on the s/pdif output .. and then possibly a custom re-write of the firmware on one of the receivers.
WAY too much work and risk.

if you wanted surround sound in both rooms, you would use the analog outputs from the soundcard and connect them to a distribution amplifier that has enough audio outputs (or use more than one for all the surround channels).

as with anything that goes into the path of a signal, the in-line hardware can degrade the signal.
so if you connect the second room setup in your pc room first, and it sounds much different in the second room.. find a better distribution amplifier (or maybe you need to upgrade your RCA cords to premium ones.)
 

anwaypasible

Distinguished
Oct 15, 2007
718
0
19,010
your graphics card needs to support the ability to use the HDMI cable.
if you connect that cord to the graphics card and the graphics card doesnt know what is going on, it might break your graphics card by shorting some pins together.
you will have to ask the manufacturer of the graphics card if your model number supports dvi to hdmi cables.
and while you are at it, you should also ask if the long cord will damage the graphics card.
50ft is a whole lot of cord to be sending electricity down.
usually the outputs of PC hardware arent ment for more than about 10ft
if the output on the graphics card screams at the top of its lungs to get the signal all the way down the cable.. it might die from all of that screaming.
that is why it says on the website 'this cable might require an HDMI repeater'

you might be right about using HDMI cable instead of the DVI connector.. because HDMI connectors have 19 pins, and the DVI connector has 29 pins.
less wires should mean less effort to send the signal.
but
if those 19 pins on the HDMI are high bandwidth
compared to the 29 DVI pins that may be medium or low bandwidth
then..
the extra bandwidth would cause more effort needed to send the signal down the cable.

unfortunately, i dont know if the pins on either connection are high bandwidth or low bandwidth.
naturally, more pins should amount to less bandwidth per pin.. one reason why there are many pins.

you are also right about wanting to split the audio output from the soundcard, because you dont want to connect the output from the distribution amp to the receiver in the same room.. that would be extra voltage going into the inputs of the receiver.
a good designed distribution amp would allow a 'bypass' or 'adjustable gain' for cables that are closer.
another design option would be to 'sense' how much resistance the cable connected to the output is.. then lower the voltage if the device 'senses' that the cable is really short.

but, you probably shouldnt be using 50ft of cable without an amplifier of some sort to boost the signal back up.
it is all about what you are asking the output to do.
one person shouldnt be expected to pull a semi truck with a rope.
its a lot of work, and the person needs to be really healthy and strong.
if you forced the person to try and pull the semi truck, they might pull a muscle from trying too hard.
pulling a muscle in electronics usually means something broke.

maybe you connect it all and it works for a couple months, but if the hardware cant handle the long cables.. all of that resistance is going to torture and murder your soundcard and graphics card.
if the signal is weak on the other end of the cable.. you might even break the touchscreen and receiver.
i would think the touchscreen would die before the receiver does.. because a receiver is an amplifier that should be able to amplify the signal coming into the input, whether the amount of electricity is 250 millivolts or 75 millivolts.

really expensive cords can go long distances without voltage drop.
but these cords vary with how far they will go before voltage starts to drop.

anyways..
your receiver in the 2nd room might break because if the voltage is too low at the inputs, then you will be forced to turn the amplifier up higher.
that puts more electricity across the electronics, and that extra electricity could lead to premature failure.
things like transistors and resistors being fed more electricity than 'normal' because you have to turn the volume up an extra 25%
you might break the receiver in a year.. and you might start having trouble with the 'protect' circuit sooner than that.

no reason to avoid a distribution amplifier, because they are basically the same thing as a repeater.. except a repeater only has one output and the distribution hardware has two or more outputs.

i seen the touchscreen you pointed to, and it doesnt have the 'three RCA cord' connection.
meaning, you should look for a different 'booster' for the connections.

dedicated preamps have been a luxory for ages.
the most simple ones simply isolate the input and outputs to prevent additional noise and/or ground hums.
more features include:
boosting the output voltage so it is higher than the input voltage
a vast amount of sound processing options

any reason to think you would need a preamp?
sure, there are some reasons i could come up with.
maybe some time delay, or an equalizer, or an automated room correction processor.. or even simply isolating the signal from the soundcard.
maybe you get one with a compressor and/or limiter to help the speakers in the 2nd room from distorting when loud bursts of audio are played.

here is a review from a person who used 50ft of hdmi cable:
http://www.amazon.com/review/R2LWM4A1IU3DLF/ref=cm_cr_pr_viewpnt#R2LWM4A1IU3DLF

the person said using the cable only left them with 800x600 resolution and no sound.. but after using the HDMI extender by the television, there was full HD video and sound again.

inputs and outputs are like connecting too many speakers to the amplifier.. eventually the amplifier will go into protect mode because there isnt enough electricity going into the amplifier as there is electricity coming out of the amplifier.
if it goes in at 10 mph and goes out the exit at 35 mph .. then it isnt going to work until the 10 mph has been brought up to speed.

electricity being output is also like weight.
if you put a giant CRT television on a junk television stand.. the 300 lb television is going to cause the particle board to collapse.
when the weight is electricity, then the television stand would be the electric circuit board inside the soundcard or graphics card.

it is like sitting on something that is too weak to hold your weight.. and while you are sitting on it, you are simply waiting for it to break.
the collapse might happen instantly, and it might happen a little bit later.
but what is the point of breaking it?
i know sometimes when it is a table, you might yell and say 'why did anybody ever buy this piece of junk? it isnt going to hold what i put on it'

they arent television trays that can magically hold 40 lbs if you dont wobble the legs.
i wish i knew more about input and output resistances, but for now.. all i can tell you is, there is no sense wasting a perfectly good television tray by sitting on it.

if you connect those pieces together without asking if the electronics can support it all.. its just like sitting on the tv tray and watching it collapse to the ground with bent metal legs.

that is why they say sometimes electronics are 'under rated'
because its like a television tray made out of 2x4 wood that can hold your weight if you sit on it.
they dont make hardware like that much anymore.
it used to be easier to find back in the 1980's and stopped in the 1990's

hopefully you will be able to use the splitter from the soundcard without putting excessive weight on the amplifier of the soundcard.
when one receiver has an input resistance of 20,000 ohms
and a second receiver has an input resistance of 20,000 ohms
using a splitter means the total load is 40,000 ohms
the electronics are designed for what? maybe 30,000 ohms?
that means you would be 10,000 ohms over.
products dont always get hot when they do extra.
instead they get hot very rapidly and fail.

sometimes it is based on heat.
if the chip is 100 degrees and ment to be safe at a maximum of 60 degrees .. the thing is going to die early.
 

pom134

Distinguished
Nov 28, 2010
3
0
18,510
OK thanks for taking the time to respond.

I used to be heavy into car audio so I am familiar with the concept of low voltage into an amp -> turn the amp gain up -> clip the amp -> break the amp. I won't run into problems of turning things up and clipping.

I also understand the concept of voltage drops across long wires and how they can degrade/damage equipment. I think the idea of using repeaters and 2 medium cords instead of just long cords is reasonable.

My card actually has HDMI outs itself, I might be able to use a straight up HDMI cable. It is a radeon 6870.
 

anwaypasible

Distinguished
Oct 15, 2007
718
0
19,010
clipping is an artifact of too much input with too much output requested.
when the input isnt too high, the situation is different.. as asking too much from the electronics wont cause clipping from the individual pieces themselves.
they actually 'sing' and show their true flaws.
when the individual pieces are connected in tandem, a slew of collapsing can happen when previous pieces 'sing' and dont fit into the pieces that comes next.

but aside from that.. transistors get more voltage across their pins, and they could fail.
resistors also get more voltage across their pins, and they could dry up faster.

extra heat from extra voltage can accelerate the damage.

(extra voltage across the capacitors can dry them up faster too)