wjm@whuxl.UUCP (MITCHELL) (07/26/84)
<gulp> The thing that control and telephone circuits have in common is that they are low voltage and LOW POWER. The National Electrical Code not only specifies voltage limits but also power limits for this class of circuit. I would suspect that most hi-fi systems being discussed on the net exceed these limits. Also, as has been often discussed on the net, you don't want to use small gauge wires (like telephone wire or the stuff sold by Radio Shack) as speaker wires. If you're going send the stuff to other rooms, you really don't want to use anything smaller than 16 ga, and 14 is more reasonable given the length of the run. The problem with using the non-metallic sheathed cable (which the National Electrical Code approves for use in some buildings - notably residential buildings of 3 or less stories) is that it doesn't provide any shielding against RFI. Personally, I wouldn't use it for house wiring, since I don't feel it affords adequate mechanical protection. Regards, Bill Mitchell (whuxl!wjm) P.S. address replies to the above address and flames to /dev/null P.P.S. don't underestimate the credentials of some of the denziens of the net.
rfg@hound.UUCP (R.GRANTGES) (07/27/84)
[Hi!] Mr. Mitchell: The problem with underestimating the credentials of some denizens of the net, as you must know, is to determine <which> denizen's credentials not to underestimate. It is true that <some> of us are world renown authorities in mufti. (authorities on what is another matter, let us assume authorities on ,say, audio.) However, it is at least equally true that it is impossible to underestimate the credentials of other denizens of the net. I'm sure we both have in mind some representatives of each camp. Perhaps that is what makes the net so fascinating: most of the time one cannot be quite sure what kind of denizen one is communing with. Also, the gentle reader should be informed (in case he/she is so dumb they haven't noticed) that even the most, highest qualified and respected among us may, occasionally fall from grace and deliver a stupid, idiotic, ridiculous opinion - even in, or near, their speciality. Of course, these remarks are not intended to apply to anything you have said recently. I agree with your views on audio house wiring, noting that you largely express your preference for BX as a personal preference. In my case I have used No. 12 and No. 14 non-metallic for reasons of performance at a price. I have had RFI which was cured in one of two ways a) I waited until the person gave up the hobbey or moved away or b) I took out a contract and had the person 'rubbed out'. Eithedr way was probably cheaper than BX, but, if I had the money I would sure do as you recommend. On the other hand, I should confess that in a 'professional' application I used 'speaker wire' of no. 14, 16 and 18 because I had lots of power (200+ watts into an Altec A-7) and little money and handling convenience was also important. Dick Grantges hound!rfg
ron@brl-tgr.ARPA (Ron Natalie <ron>) (08/02/84)
Sorry, but shielding speaker cables is not to keep the audio signal in it's to keep other shit out. This is preferable to the kludge of putting a low pass filter on the speaker terminals to cut off RF since this doesn't always work, the RF may have been rectified before the point where the capacitor is attached. The best way to remove RFI is not to let it in to begin with. -Ron P.S. Believe me, I know. I used to live two blocks away from an AM radio station.
crandell@ut-sally.UUCP (Jim Crandell) (08/04/84)
> That's it, I'll go into business selling audio waveguide. Should be a good > market for it.... Yeah. Fabulous idea. Bury it in the ground, of course. Then, when the novelty wears off and you're no longer interested in transmitting audio through it, you can use it to shuttle, say, Cleveland back and forth across the continent. -- Jim Crandell, C. S. Dept., The University of Texas at Austin {ihnp4,seismo,ctvax}!ut-sally!crandell