mberns@ut-ngp.UUCP (Mark Bernstein) (01/10/86)
[] We'd appreciate some advice, and quickly as possible; hope some of you can help (e-mail would be just fine). My wife and I are building a house, and we're in the framing stage right now. Interior electrical and plumbing work will begin in just a week or two. We are locating our stereo system in a central built-in location and plan to pre-wire for speaker outlets in various locations which have been selected. Facts whose relevance will quickly become apparent: Our system is by no means a high end audiophile system; it is simply a fairly good- sounding conventional moderate-budget group of components put together through several upgrades over the past few years. Scott 359RS receiver (50w/channel), high-end Hitachi turntable with Audio-Technica cartridge, medium quality Teac cassette deck, a pair of Frazier "black box" speaker systems cosmetically set up for home use. For our personal tastes, priorities, and budget, the system is quite satisfactory for us (although, as a regular reader of this net.group I am well aware that it is far from state-of-the-art!), so no changes are contemplated there. Given this as background, my questions concern some details of the wiring we'd be doing. First, the longest speaker cable runs would be on the order of 35-40 feet. I know the nature of the wiring is critical in order to prevent degrading the signal (for example, I wouldn't use simple 18 ga. lamp wire), but I also don't want to go into big $ overkill either (say, "Monster Cable", gold plated connectors, etc. - I haven't been interested in these up to now, and don't want to spend the money on them, anyway). I simply want to be reasonably sure that the system won't sound any different (worse) than it does now. I'm thinking of using something like 14 ga. or 12 ga. solid copper Romex. Is this a reasonable choice which will perform satisfactorily for *this* system? Is the 12 ga. necessary just to be sure? Second, for those runs where the wire has to go a distance inside a long wall (as opposed to running in between ceiling joists) it would be convenient for me to simply use the same holes through the studs that the electrician would be making for his AC wiring in that room, thus saving me a significant amount of time drilling separate holes for the speaker wiring. The speaker wires would then be running parallel to, and very close to, the AC wires. Would this be a terrible mistake? I'm thinking of the danger of picking up 60 Hz hum, etc., if that's possible. If I should drill my own holes, how far from any AC lines should I place the speaker wiring? [ :-) I realize I'm flirting with danger asking simple-minded questions about such a sound system in this net.group. I can already hear the groans from some individuals. :-) But I would appreciate some solid advice about how to handle this. ] Many thanks, Mark Bernstein (UT Austin, Speech)
reid@glacier.ARPA (Brian Reid) (01/11/86)
A few years ago I wired my house for audio, and I learned a few things. >Our system is by no means a high end audiophile system... , the system is >quite satisfactory for us (although, as a regular reader of this net.group >I am well aware that it is far from state-of-the-art!) Your house will last a lot longer than your stereo. There is no reason not to wire the house as if your stereo were the best; perhaps someday you might change your mind or want to sell the house. As long as you're going to go the trouble of doing it at all you might as well do it right. > I'm thinking of using something >like 14 ga. or 12 ga. solid copper Romex. Is this a reasonable choice >which will perform satisfactorily for *this* system? I used 12-ga. Romex, 3-wire, and have never been sorry. It is a few cents a foot more expensive and a bit more difficult to route through joist holes, but it will handle anything. Because speaker voltages are lower than household voltages, you actually need thicker wire to carry the same power load. Monster Cable doesn't work any better than 12-gauge Romex, but it is a lot prettier, so if you are going to run a cable through the middle of your living room you will probably want to use Monster Cable. As long as you have the luxury of running the cable through the walls, then use Romex. >Second, for those runs where the wire has to go a distance inside a long >wall (as opposed to running in between ceiling joists) it would be convenient >for me to simply use the same holes through the studs that the electrician >would be making for his AC wiring in that room, thus saving me a >significant amount of time drilling separate holes for the speaker wiring. Because speaker wires are paired and power wires are also paired, the inductive pickup at that impedance will be negligibly small (though measurable). However, you might have some code problems if you aren't careful. According to my copy of the National Electrical Code, 1984 edition, Article 725, if you want to run speaker wires "in the same enclosure, cable, or raceway" with power wires, then they must be considered "Class 1 circuits". This means that they must meet various fuse, insulation, and transformer guidelines, and in general must be approved by the electrical inspector. Here in Palo Alto I talked to one electrical inspector who said that if he signed off on my speaker wires as Class 1 wiring that would require me to have a re-inspection if I bought a new power amplifier. I'm not sure that is true (the wording of the electrical code is somewhat vague). I ran them as Class 2 wiring (more stringent requirements) just to be safe. If you don't want the stereo to have to meet Class 1 requirements, then they are going to be called "Class 2 and Inherently current-limited". The code for this kind of wire says "Conductors of Class 2 ... circuits shall be separated at least 2 inches from conductors of any electric light, power, or Class 1 circuits". Summary recommendations, based on having done this and then lived with the results for 3 years: * Run only the best wire. Your house is more permanent than your stereo. 12-gauge Romex is good enough. * Run wires to more places than you think you will want. You won't have the opportunity to change your mind later, and you might want to move your speakers. * Use knurled binding posts, rather than RCA plugs or phone plugs, for the connection. The speaker wires will wiggle loose from the other kinds of connectors. * Use a different color Romex for the speaker wires than you use for other house wires. At some time in the future you might want to cut into a wall to install a new speaker outlet, and it's nice to be able to tell the identity of the wires without cutting into them and measuring voltages. * While you're running wires, run 75-ohm coaxial cable lines into every room that has speakers. It's good for TV, FM radio, etc. -- Brian Reid decwrl!glacier!reid Stanford reid@SU-Glacier.ARPA
jaw@ames.UUCP (James A. Woods) (01/18/86)
# fools ignore complexity. pragmatists suffer it. some can avoid it. geniuses remove it. -- perlis's programming proverb #58, sigplan notices, sept. l982 ----- in the future, your grandkids will ask "mommy, daddy, what were wires?" in the near future, you'll mumble "wish i knew that company XYZ was coming out with infrared/RF/what-have-you stereo xmission directly to the speakers, or better yet, that model with the receiver chip built right into the speakers themselves, ... before i wired that house." the future (in powerelectrooptics, or in consumer audio, at any rate) is closer than most people think. seems like the technological overkill here is even applied to the wrong subsystem.(*) ok, it's safe to go back to your collective 1985 unimagination now. but wait, before you do, try to think of a 1986 "high end" japanese audio company schemeing to somehow get folks to rig up their nice compact 6-tatami mat houses with "monster cable". or try to imagine them catering to the luxury of having corner klipschorns or american-style 30" tv "tubes". hell no, they're working like mad on flat audio as well as video transducers (made out of ricepaper for all we know), power systems built into amorphous roof tiles, jukeboxes on bloch-wall bubble chips, remote controls that make current stuff look sick (just say "osawa, four seasons, summer"), ad infinitum. so while we american brute-force audio dinosaurs (a good subject for a gary larson cartoon) violate a very basic principle used by art restorers everyday (never use materials or techniques which might not be easily undone by future technologists with a better idea) by "wiring" houses for "audio", they are chuckling at our fumbling incompetence. sincerely, james a. woods (ames!jaw) ----- (*) actually, some would argue that power wires are as unsightly as speaker wires are ungainly, albeit with the better placement independent of the control box. so, for you, we have high efficiency folded horns powered by rechargeable batteries. what? -- don't like to drag your speaker across the room to be charged up? well, then, in rodriguez fashion, how about microwave beamed power xmission, modulated with the audio now feasible as infrared carrier? hmmm...settle for headphones? no? don't like the cocktail party sound cutoff...shoulder phones?... ceiling beams?...
reid@glacier.ARPA (Brian Reid) (01/19/86)
For a minute there I thought ames!jaw was just quoting the liner notes from "Stop making sense". Except that he didn't quote the line "In the future, women will have breasts all over", so I knew he was just making it up. Right. This reminds me a lot of the article that appeared in @i[Science] magazine in the middle 1970's (for those of you not familiar with it, @i[Science] is an archival-quality refereeed journal devoted primarily to biology and medicine). Anyhow, it predicted that furnaces would be obsolete because peoples' houses would be wired with microwave emitters that would radiate low-energy high-frequency energy directly into their bodies. The author of the article worked out all of the math and showed that nobody would be injured, and showed further that if one person got too hot he could wear a metallic jacket to cool off. My telephone wires are obsolete too. I think I'd better put in glass fiber right away. -- Brian Reid decwrl!glacier!reid Stanford reid@SU-Glacier.ARPA
dbrichards@watnot.UUCP (the vegit man) (01/20/86)
> in the future, your grandkids will ask "mommy, daddy, what were wires?" > the future (in powerelectrooptics, or in consumer audio, at any rate) >is closer than most people think. > james a. woods (ames!jaw) I had heard of a product which was shown at the 1985 Winter CES in Las Vegas which was an infrared (?) headphone connection. You simply plugged the main box into the PHONES jack, then put on the pair of wireless headphones, and you could move anywhere in the room and listen without making any noise. Has anybody heard anything more about this product? - Dennis -- -------------------------------------------------------------------------------- Dennis Richards R:"Batman, there's a Polaris-type missile headed Faculty of Mathematics straight at us!" University of Waterloo B:"Hang on, Robin, this might be tricky." UUCP: {allegra,ihnp4,decvax,utzoo,clyde}!watmath!watnot!dbrichards CSNET: dbrichards%watnot@waterloo.CSNET ARPA: dbrichards%watnot%waterloo.csnet@csnet-relay.ARPA
marvinm@ttidcb.UUCP (Marvin Moskowitz) (01/24/86)
In article <11400@watnot.UUCP> dbrichards@watnot.UUCP (the vegit man) writes: >> in the future, your grandkids will ask "mommy, daddy, what were wires?" >> the future (in powerelectrooptics, or in consumer audio, at any rate) >>is closer than most people think. >> james a. woods (ames!jaw) > >I had heard of a product which was shown at the 1985 Winter CES in Las >Vegas which was an infrared (?) headphone connection. You simply plugged the >main box into the PHONES jack, then put on the pair of wireless headphones, >and you could move anywhere in the room and listen without making any >noise. > > Has anybody heard anything more about this product? > >- Dennis The Shubert Theater in Los Angeles (actually Century City) has such notoriously LOUSY acoustics, that they rent infra-red headphones made by Sennheiser. Sounded worse than without, but I couldn't tell if it was a problem with the 'phones (all 4 we rented SUCKED) or the source transmission.