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#1
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Okay, I know that RF cables are meant for video, not audio.
But the video newsgroups seemed to be full of noise, and I suspect many audiophiles watch television every now and then, so here goes. When I look at the plug end of an RF cable, I can see some differences between brands. The really cheap cables, and even some medium priced cables, have the inner wire surrounded by very little white plastic insulation material. I've seen some cables where the inner wire can touch the metal portion of the plug with just a little movement. If I look at a Monster cable, there is a substantial amount of white plastic insulation, and it fills the cavity so the inner wire cannot move at all. To quote Martha Stewart, this is a good thing. What about Acoustic Research cables? From online photos (I cannot seem to find one to see in person) AR cables look nice and fat (good insulation), and have the knurled ends to turn (instead of the hexagonal ends which aren't as easy to turn), but I cannot see inside the plug to see the white insulation. Anyone own an AR cable? Lee |
#2
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"Lee" wrote ...
Okay, I know that RF cables are meant for video, not audio. But the video newsgroups seemed to be full of noise, and I suspect many audiophiles watch television every now and then, so here goes. When I look at the plug end of an RF cable, I can see some differences between brands. The really cheap cables, and even some medium priced cables, have the inner wire surrounded by very little white plastic insulation material. I've seen some cables where the inner wire can touch the metal portion of the plug with just a little movement. If I look at a Monster cable, there is a substantial amount of white plastic insulation, and it fills the cavity so the inner wire cannot move at all. Most of us just use cables to conduct signals from one place to the other. Those who like looking at and fondling cables more likely prefer "Monster" and other "boutique" brands at rip-off prices. If you can't see/hear the difference in the signal, it's not worth the money. Period. |
#3
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Most of us just use cables to conduct signals from one place
to the other. Those who like looking at and fondling cables more likely prefer "Monster" and other "boutique" brands at rip-off prices. If you can't see/hear the difference in the signal, it's not worth the money. Period. The really cheap cables can have enough capacitance to cause changes in frequency reponse with some amps/preamps with long cables. I needed about 30' between a preamp and the power amps and wound up making cables from surplus coax cable, a military type with Teflon insulation, silver-plated shield, and a very low capacitance per foot. Cables were measured on a GR 1650 impedance bridge, if anyone cares. Mike Squires -- Mike Squires ) 317 233 9456 (w) 812 333 6564 (h) 546 N Park Ridge Rd., Bloomington, IN 47408 |
#4
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"Lee" wrote in message . earthlink.net...
Okay, I know that RF cables are meant for video, not audio. But the video newsgroups seemed to be full of noise, and I suspect many audiophiles watch television every now and then, so here goes. When I look at the plug end of an RF cable, I can see some differences between brands. The really cheap cables, and even some medium priced cables, have the inner wire surrounded by very little white plastic insulation material. I've seen some cables where the inner wire can touch the metal portion of the plug with just a little movement. If I look at a Monster cable, there is a substantial amount of white plastic insulation, and it fills the cavity so the inner wire cannot move at all. To quote Martha Stewart, this is a good thing. What about Acoustic Research cables? From online photos (I cannot seem to find one to see in person) AR cables look nice and fat (good insulation), and have the knurled ends to turn (instead of the hexagonal ends which aren't as easy to turn), but I cannot see inside the plug to see the white insulation. Anyone own an AR cable? Lee I don't want to spoil your fun, but RF cables require a termination equal to the characteristic impedance of the cable itself. Your speakers are not 75 Ohms! RF cables won't act as "RF cables" into an 8 Ohm load. You can buy speaker wire with 8 Ohms characteristic impedance. I know this has been said hundreds of times before but, nothing beats Home Depot's 12 gage speaker wire. Bob Stanton |
#5
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I don't want to spoil your fun, but RF cables require a termination
equal to the characteristic impedance of the cable itself. Your speakers are not 75 Ohms! RF cables won't act as "RF cables" into an 8 Ohm load. You can buy speaker wire with 8 Ohms characteristic impedance. I never mentioned anything about speakers, but you assumed I wanted to use video cables as speaker wire. Do you always answer questions that weren't asked? Lee |
#6
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"Lee" wrote in message rthlink.net...
I don't want to spoil your fun, but RF cables require a termination equal to the characteristic impedance of the cable itself. Your speakers are not 75 Ohms! RF cables won't act as "RF cables" into an 8 Ohm load. You can buy speaker wire with 8 Ohms characteristic impedance. I never mentioned anything about speakers, but you assumed I wanted to use video cables as speaker wire. Do you always answer questions that weren't asked? Lee Are you always such a **** head? Bob Stanton |
#7
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You can buy speaker wire with 8 Ohms characteristic impedance.
Talk about your snake-oil hucksterism!!! There's one born every millisecond. |
#8
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On 27 Jul 2003 03:52:13 -0700, Bob-Stanton wrote:
You can buy speaker wire with 8 Ohms characteristic impedance. Name a *single* example, please. Otherwise it's obvious you're talking out your ass. Transmission line effects only come into play if the cable is at least 1/2 wavelength. At audio frequencies, this'll be measured in miles. Do you typically run 10 miles of speaker wire? |
#9
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Bob-Stanton wrote:
You can buy speaker wire with 8 Ohms characteristic impedance. "TCS" wrote ... Name a *single* example, please. Otherwise it's obvious you're talking out your ass. Or Mr. Stanton is quoting know-nothing, schyster, snake-oil cable salesmen! Of course it doesn't make any sense technically, but it would sure sound good to a customer with deep pockets and shallow knowledge of electronics. (i.e. you typcial "Monster" et.al. cable customer) I'm sure even you, "TCS" could come up with a plausible- sounding line of bull. Something like the "benefit of better power coupling resulting from proper impedance matching of the cable" or some such silliness. |
#10
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You can buy speaker wire with 8 Ohms characteristic
impedance. What, at audio frequencies? How many miles of cable are we talking about here? :-) |
#11
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TCS wrote in message news:slrnbi90vr.h1b.The.Central.Scrutinizer@linux .adamf625.kaosol.net...
On 27 Jul 2003 03:52:13 -0700, Bob-Stanton wrote: You can buy speaker wire with 8 Ohms characteristic impedance. Name a *single* example, please. Otherwise it's obvious you're talking out your ass. How about four examples. Alpha-Core, Goetz, Dunlavy and even Radio Shack. Ribbon cables, two flat conductors close together, have characteristic impedances of typically 8 Ohms. Dunlavy specified his cable's characteristic impedance at 6 Ohms. Transmission line effects only come into play if the cable is at least 1/2 wavelength. Wrong, transmission line effects occure at all wavelenghts. For example, a 50 ft length (1.016 E-3 wavelengths) of 100 Ohm characteristic impedance, speaker wire (such as Home Depot's) will have a loss of about 0.01 dB at 20kHz, due to the reflection caused by the impedance mismatch. (At lower frequencies the loss is much less than 0.01 dB.) At audio frequencies, this'll be measured in miles. At 1000 Hz, 1/2 wavelenght = 93 miles. Do you typically run 10 miles of speaker wire? Yes, I do, but the insertion loss is terrible. I'm thinking about moving the speakers closer to my house. Bob Stanton |
#12
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"Richard Crowley" wrote in message ...
Bob-Stanton wrote: You can buy speaker wire with 8 Ohms characteristic impedance. "TCS" wrote ... Name a *single* example, please. Otherwise it's obvious you're talking out your ass. Or Mr. Stanton is quoting know-nothing, schyster, snake-oil cable salesmen! Of course it doesn't make any sense technically, but it would sure sound good to a customer with deep pockets and shallow knowledge of electronics. (i.e. you typcial "Monster" et.al. cable customer) If you go back and reread my message, you will notice I did *not* recommend buying an expensive 8 Ohm (characteristic impedance), speaker cable. I mearly mentioned that such cable was available. This type of cable has only one pratical advantage over regular speaker cable, it will cause less of a bump when run under a rug. I recommended Home Depot's 12 gage speaker cable, which has a characteristic impedance of around 100 Ohms. This is an inexpensive but very adequite, speaker cable. Bob Stanton |
#13
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"Lee" wrote in message news:cnRUa.23740
I never mentioned anything about speakers, but you assumed I wanted to use video cables as speaker wire. Do you always answer questions that weren't asked? Pardon me for not reading your message carefully. I assumed that because you posted your message in an *audio* group, your message was somehow related to audio. Perhaps you should look for a group that more discusses video. Do you always post your questions to the wrong group? Bob Stanton |
#14
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"TCS" wrote ...
0.01DB? Thanks for agreeing with me. IOW indistinguishable from natural noise and instrument calibration. Or do you realize that you have just conceded your argument? |
#15
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Laurence Payne wrote in message . ..
You can buy speaker wire with 8 Ohms characteristic impedance. What, at audio frequencies? How many miles of cable are we talking about here? :-) 93.1 miles Bob Stanton |
#16
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Michael Squires wrote:
Most of us just use cables to conduct signals from one place to the other. Those who like looking at and fondling cables more likely prefer "Monster" and other "boutique" brands at rip-off prices. If you can't see/hear the difference in the signal, it's not worth the money. Period. Concur, spend the money where it matters. The really cheap cables can have enough capacitance to cause changes in frequency reponse with some amps/preamps with long cables. Sounds like a case of a preamp with a **** poor line driver stage to me, I would get it replaced with something competently designed. I needed about 30' between a preamp and the power amps and wound up making cables from surplus coax cable, a military type with Teflon insulation, silver-plated shield, and a very low capacitance per foot. 30ft is a long cable? On what planet? I routinely run mic level signals (which often have source impeadences many times that of a decent line driver stage) down 100+M (300+ft) mulicores and it all seems to work just fine. Now sometimes you can hear a difference in the special case of a ribbon mic, but for anything with a reasonable amount of drive available (and anything with a line output should have a reasonable amount of drive available) 30ft is *NOTHING* . Cables were measured on a GR 1650 impedance bridge, if anyone cares. I really would not sweat the details like this, there are things which make far larger differences to the quality of reproduction (of audio or video) then the "wow these cables are really expensive" factor. Spend the money on better room lighting (for video), better acoustic treatment, better speakers, better processing...... For video, I normally choose a decent 75ohm cable (then terminate with 50ohm BNC (more mechanically robust, the electrical length of the connector is neglegable for baseband video)). For long runs a Balun and 110ohm twisted pair can have some advantages (most buildings are now wired with lots of CAT5, which can be *really* convinient). Regards, Dan. -- ** The email address *IS* valid, do NOT remove the spamblock And on the evening of the first day the lord said........... ..... LX 1, GO!; and there was light. |
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