[LAU] OT: audio over phone line (not dsl)

frank pirrone frankpirrone at gmail.com
Sun May 10 15:15:25 EDT 2009

Aaron L. wrote:
> Long time lurker here.
> .......who's very first post is a bit off topic. 
> However, in the sense of diy (and there being some great brains in 
> this room), I'd love to hear someones thoughts about this article.
> http://www.mcmelectronics.com/content/en-US/diy/baluns
> Scroll down to the yellow number 3.
> Please ignore this if it's too off-topic. 
> I'm still catching up on that last Gentoo thread anyway....
> Thanks!
> -Aaron
Well, Aaron, it's not off-topic as long as you're going to be playing 
the music from a GNU/Linux system, and if at least some of what you'll 
be playing is your own work created with F/OSS tools! 

Thoughts:  Seems sound and straight-forward. 

The whole point of the tip is to spare the need to pull wire/cable 
through the wall.  Another take might be that Cat4, or Cat5, would be 
easier and cheaper to pull even if there wasn't an existing jack where 
you needed.

I did a run of Cat5 from the study where my computers and some audio 
equipment is located, and also where my FiOS wireless router is, up to 
the attic, along the floor boards, and down into the back bedroom, 
terminated on each end by RJ45s and wall plates.  I also pulled up from 
the basement a Cat4 phone line and a romex power line from at dedicated 
and well-grounded GFI breaker through the same stud box as the coax for 
the router, installing a nice 4-outlet receptacle box to power up my 
computing gear and accessories.

Sorry about the generally irrelevant details, but my point is that 
pulling or dropping wire up and down between the studs of a typical 
frame house, especially with an attic and basement.  So, I wouldn't shy 
away from going after just the cabling and outlets you need for 
convenience and productivity.

As far as the baluns go that are specified in this article, their 
purpose is to match the impedance of the balanced (bal) Cat4 running 
through the walls with the unbalanced (un) coaxial cable running to the 
audio equipment in the room.  What I meant by my cable-pulling 
suggestion above is that this is still a valid solution even if you're 
starting out from scratch into that room. 

Multi-conductor Cat4 or Cat5 cable would give you telephone and audio 
and even Ethernet if desired.  It's cheap, light, easy to pull and 
terminate, and versatile.  I'd certainly choose to run that over 
dedicated coaxial cable from the audio source.  Then, while you're at 
it, if you wind up pulling your own wires, you could add - or have an 
electrician add - some power outlets too, for just a couple bucks.  My 
1926-construction house really appreciated the extra 3-wire outlets.

p.s.  Without those baluns, you'd be humming a sixty Hertz tune, fer sure...

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