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#81
Posted to rec.audio.tech
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Advice on speaker wire needed.
Mr.T wrote:
"Don Pearce" wrote in message ... I should perhaps add that while in itself it has no great significance, it does offer some insight into the internal working of the amplifier and the general quality of the design. But not in any kind of linear relationship, i.e. a bigger 'damping factor' doesn't imply a better amplifier, once you get past 50 or so. No, but a SS amp with a really poor output impedance rings all sorts of alarm bells for reasons unconnected with impedance. It usually means it's got minimal feedback. That may ring alarm bells in a cheap amp I suppose. MrT. It will ring even louder for an expensive amp! It's just the sort of stuff that audiophools fall for. Minimal or no feedback, high distortion, high output impedance, of course it will sound different in a dealer's demo, and as in audiophool parlance difference = better, it will sell, and another sucker is taken in. S. |
#82
Posted to rec.audio.tech
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Advice on speaker wire needed.
"Don Pearce" wrote in message ... I should perhaps add that while in itself it has no great significance, it does offer some insight into the internal working of the amplifier and the general quality of the design. But not in any kind of linear relationship, i.e. a bigger 'damping factor' doesn't imply a better amplifier, once you get past 50 or so. No, but a SS amp with a really poor output impedance rings all sorts of alarm bells for reasons unconnected with impedance. It usually means it's got minimal feedback. That may ring alarm bells in a cheap amp I suppose. Which in its turn implies that there is very little internal open loop gain, which in turn could imply that the voltage amplifier is rather lightly supplied with dominant pole compensation in order to prop up the top end. The result of all of this would be marginal stability at the top end. Not sure that price has a lot to do with it, as this kind of thing has been seen in quite expensive amps - some even seem to consider it a "feature". Unfortunately very true. The inverse is also true, there have been many dubious attempts at trying to make crap amps work by the addition of copious amounts of negative feedback. Quality is simply not measured by the damping factor. MrT. |
#83
Posted to rec.audio.tech
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Advice on speaker wire needed.
"Serge Auckland" wrote in message ... It will ring even louder for an expensive amp! It's just the sort of stuff that audiophools fall for. Minimal or no feedback, high distortion, high output impedance, of course it will sound different in a dealer's demo, and as in audiophool parlance difference = better, it will sell, and another sucker is taken in. Just the same as suckers who think large amounts of negative feedback always makes an amp great, I suppose. If I'm comparing amp specs, damping factor is the last thing on my list. MrT. |
#84
Posted to rec.audio.tech
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Advice on speaker wire needed.
Pooh Bear wrote:
TimPerry wrote: Pooh Bear wrote: TimPerry wrote: Pooh Bear wrote: TimPerry wrote: GoPack wrote: I have a house heavily wired with Video Coax cable and Cat5 network cables. Can either of these be adapted to use as speaker cables? If so, how? Thanks SM cat 5 is becoming more popular for use in fixed audio installs, i guess do to low price and the availability of telephone and computer guys familiar with it. see http://www.studiohub.com/ for running audio and stuff through cat 5. for small bookshelf type speakers you could strip back all 8 conductors .. then twist blue/white and white/blue together and repeat for each color pair. that gives you 4 conductors. select a color for left + another for left - and so on. The wire's cross-sectional area is far too small to be any good as speaker cable. Graham even a single strand of 24GA isnt that much different in size then the wire that comes with most small home stereo systems. Not true actually but in any event hardly the point. Graham there is a wonderful system known as 70 volt (somtimes 100 volt or an older type 25 volt audio. this involve step up and step down transformers at each end of the wire. the advantage is you can parallel all the wires in the house together and put speakers in every room of the house all on the same audio amplifier. AND it eliminates most or all the issues that Graham is concerned about. 'course if wont be true hifi to a purest... the the PO only said "speakers".... 70 or 100 volt lines are shockingly poor quality on account of the transformers. Graham i think the 'poor quality' is more do to the $3 speakers that are often used plus cheapo paging mics. |
#85
Posted to rec.audio.tech
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Advice on speaker wire needed.
Mr.T wrote:
"Walt" wrote So you think a long length of unshielded wire is OK for line level signals? Absolutely, if the signals are balanced. I've run balanced signals several thousand feet on unshielded cable with no problem. What HiFi equipment is that? (nobody mentioned PA gear or balanced signals) IMO going balanced in a HiFi system is unlikely to be cost effective solution. Adding balancing circuitry to consumer hi fi gear is probably cheaper than pulling new wires. If the budget is tight, you can often get away with just balancing the input while leaving the output single ended. (common mode rejection works even if there is no signal present on one of the conductors) Figure $100 or so to do just the inupt end, $200 to balance the signal at both ends. Or if you use powered speakers that have a balanced input, it might not cost anything extra at all. Well, beyond the cost of the powered speakers. Even for pro audio use the current trend is going digital. Agree completely. Which is one of the reasons cat5 is being installed for analog use - just because the signal is analog today doesn't mean that it won't be upgraded to digital in the near future. Might as well install cables that can handle both. //Walt |
#86
Posted to rec.audio.tech
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Advice on speaker wire needed.
Mr.T wrote:
"Walt" wrote If you try to use one cat 5 cable to run stereo speaker signals, you're looking at 21 gauge at best. Can you say "highly sub-optimal"? Can you say quite good enough for background muzak. No, I can't say that. Allow me to repeat myself: "neither wire appropriate for speaker level signals. It might be passible for very low level background level, but not for any kind of foreground application." //Walt |
#87
Posted to rec.audio.tech
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Advice on speaker wire needed.
"Mr.T" wrote: IMO going balanced in a HiFi system is unlikely to be cost effective solution. A balanced input costs very, very litle more than an unbalanced one actually and the outputs themselves don't actually need to be balanced to get the advantage that a balanced input gives you. Even for pro audio use the current trend is going digital. And AES3 digital audio is balanced. Graham |
#88
Posted to rec.audio.tech
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Advice on speaker wire needed.
TimPerry wrote: Pooh Bear wrote: 70 or 100 volt lines are shockingly poor quality on account of the transformers. Graham i think the 'poor quality' is more do to the $3 speakers that are often used plus cheapo paging mics. In equal measure I reckon actually. Graham |
#89
Posted to rec.audio.tech
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Advice on speaker wire needed.
Pooh Bear wrote:
TimPerry wrote: Pooh Bear wrote: 70 or 100 volt lines are shockingly poor quality on account of the transformers. i think the 'poor quality' is more do to the $3 speakers that are often used plus cheapo paging mics. In equal measure I reckon actually. These things feed on themselves - "No need to use a U87 given those crap ass speakers." "No need to use decent speakers with those nasty paging mics." "Why bother with decent anything since it's all going through those awful transformers." It lends new meaning to the term "feedback cycle". //Walt |
#90
Posted to rec.audio.tech
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Advice on speaker wire needed.
Walt wrote: Pooh Bear wrote: TimPerry wrote: Pooh Bear wrote: 70 or 100 volt lines are shockingly poor quality on account of the transformers. i think the 'poor quality' is more do to the $3 speakers that are often used plus cheapo paging mics. In equal measure I reckon actually. These things feed on themselves - "No need to use a U87 given those crap ass speakers." "No need to use decent speakers with those nasty paging mics." "Why bother with decent anything since it's all going through those awful transformers." It lends new meaning to the term "feedback cycle". Given the typical application of 70 / 100 V line ( paging - PA in the sense of railroad terminals and airports etc ) it's no great surprise that quality isn't a great consideration. Graham |
#91
Posted to rec.audio.tech
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Advice on speaker wire needed.
On Wed, 7 Jun 2006 22:21:07 +1000, "Mr.T" MrT@home wrote:
"Stewart Pinkerton" wrote in message news Bull****. Variations of 3 to 20 ohms are quite common in modern speakers, which will give a highly audible 5dB variation in level with a 3 ohm cable. As someone else already noted, you don't want much more than 100 milliohms in the loop. That's about ten or fifteen feet of the kind of cheap speaker wire they give away when you buy speakers. That's going from one extreme to the other! To say that 3 ohms (quite high for just about any house run) *may* give a couple of dB variation and thus be audible, is one thing, but to claim you HAVE to go as low as 100 milliohm is stretching your credibility. Not really. 3 ohms would be about right for what he was considering, and a 5dB variation is *highly* audible. Agreed, but are 1dB variations? Name one speaker that can do better than that? I'm talking about variations from the speaker's existing response, not absolute flatness per se. And yes, a 1dB change is audible. (You don't need 100 millohms to get less than 1dB) Depends on the speaker. OTOH, 100 milliohms isn't hard to achieve for very little cost in most systems, so why not just take cable impedance right out of the equation? 100 milliohms is not hard to achieve with decent wiring, and pretty much guarantees no problems unless you have *really* bizarre spekares, which is why it's a reasonable benchmark. Y Says who? With most speakers it is simply overkill. Sure it is cheap easy overkill which I also do myself, but to claim it is necessary, is not true in the *VAST* majority of cases. I didn't say it was necessary, I said it was a reasonable and easily achieved benchmark. Get over yourself, BA. ou could have 8 ohms of wire without problems with the *constant* 4-ohm impedance of the KEF 104aBs I used to own, due to their cunningly contrived constant impedance - but they would have sounded like sh1t compared to modern speakers. You really believe modern "white van" speakers are better than the KEFs? Such unqualified statements are what caused this argument in the first place. Modern mainstream speakers of equivalent price is the obvious context. Stop whining, just because you lost the argument. Zero ohms is lovely and all that, but you're not likely to pick much less than one ohm without an A/B direct comparison, in the *majority* of cases. And less than one ohm is not hard to achieve. Indeed, it's a piece of **** in most installations. I wouldn't even *think* of having more than 0.1ohm without good reason Me either, but only because it's cheap and easy to do. I'm not silly enough to claim it is imperitive. Neither is anyone else. Also I doubt he has perfect speakers to start with, extra resistance will even improve some of them! Sheer conjecture. Exactly, just like your statements. Nope, you're just whining because your knee-jerk bull**** was deconstructed. -- Stewart Pinkerton | Music is Art - Audio is Engineering |
#92
Posted to rec.audio.tech
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Advice on speaker wire needed.
"Walt" wrote in message ... If you try to use one cat 5 cable to run stereo speaker signals, you're looking at 21 gauge at best. Can you say "highly sub-optimal"? Can you say quite good enough for background muzak. No, I can't say that. It might be passible for very low level background level, You just did say that then, only in slightly different words. MrT. |
#93
Posted to rec.audio.tech
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Advice on speaker wire needed.
"Pooh Bear" wrote in message ... A balanced input costs very, very litle more than an unbalanced one actually Quite true in the world of pro audio. How many balanced systems do you find in your local HiFi shop though? I can't recall seeing any myself. Even for pro audio use the current trend is going digital. And AES3 digital audio is balanced. And cat5 could be used. MrT. |
#94
Posted to rec.audio.tech
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Advice on speaker wire needed.
"Stewart Pinkerton" wrote in message ... I'm talking about variations from the speaker's existing response, not absolute flatness per se. And yes, a 1dB change is audible. In an A-B test, which I already said. (You don't need 100 millohms to get less than 1dB) Depends on the speaker. OTOH, 100 milliohms isn't hard to achieve for very little cost in most systems, so why not just take cable impedance right out of the equation? Which I already said, but has nothing to do with THIS case. Says who? With most speakers it is simply overkill. Sure it is cheap easy overkill which I also do myself, but to claim it is necessary, is not true in the *VAST* majority of cases. I didn't say it was necessary, I said it was a reasonable and easily achieved benchmark. I'm glad you *now* agree it is just an easily achieved overkill. ou could have 8 ohms of wire without problems with the *constant* 4-ohm impedance of the KEF 104aBs I used to own, due to their cunningly contrived constant impedance - but they would have sounded like sh1t compared to modern speakers. You really believe modern "white van" speakers are better than the KEFs? Such unqualified statements are what caused this argument in the first place. Modern mainstream speakers of equivalent price is the obvious context. Stop whining, just because you lost the argument. Sorry I didn't realise there was judging, and you were the sole judge. You really should understand the need to clearly define what you are talking about BEFORE hand then. Not *after* someone questions your nebulous statements. Me either, but only because it's cheap and easy to do. I'm not silly enough to claim it is imperitive. Neither is anyone else. Good, I'm glad you have stopped then. Maybe we can get on with something else. Sheer conjecture. Exactly, just like your statements. Nope, you're just whining because your knee-jerk bull**** was deconstructed. Only in *your* opinion of course. I'm glad I'm not so up myself as you are at least. MrT. |
#95
Posted to rec.audio.tech
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Advice on speaker wire needed.
"Mr.T" wrote: "Pooh Bear" wrote in message ... A balanced input costs very, very litle more than an unbalanced one actually Quite true in the world of pro audio. It only needs a few exrta resistors if each input has an op-amp buffer. How many balanced systems do you find in your local HiFi shop though? I can't recall seeing any myself. Perfectly true. The tyranny of the utterly useless rca connector may be to blame. That's not to say it's impossible to make hi-fi with balanced ins though. Indeed there's simply no excuse for high end stuff not to. Even for pro audio use the current trend is going digital. And AES3 digital audio is balanced. And cat5 could be used. Only if you disregard the AES recommendation that AES3 be screened. Graham |
#96
Posted to rec.audio.tech
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Advice on speaker wire needed.
Pooh Bear wrote in
: David Nebenzahl wrote: Dave Platt spake thus: Whether this change in frequency response will be significant, audible, or objectionable in a particular installation is likely to be a subjective issue. For medium-fi remote speakers, probably not... but for critical listing with high-fidelity speakers it might very well make the difference between an acceptable install and an unacceptable one. Well, I didn't address that point, because it's moot anyhow: if this were an anal audio-fool's installation, they'd have 1-gauge copper bus connectors throughout the house, running inside industrial noble-gas-filled conduit, for their speaker wiring. (Or maybe superconducters.) For anyone else, it makes practically NO difference. You really do talk out of your ass you know. Nettkkkpping ****. interesting to see you work and play as wel with others just the same no matter what the venue. Bertie |
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