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Post by MusicHead on Jan 17, 2016 16:59:14 GMT -5
Jumpers are also much shorter than any wire you are ever going to use. Again, unless they are made of utterly, abismally bad metal, what influence can an inch of metal have?
Not to mention that jumpers might be thin, but they are wide. The equivalent cross section is not that small.
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Post by Boomzilla on Jan 17, 2016 17:18:12 GMT -5
re: jumpers. I'll make one additional observation. In a loudspeaker system that uses them, be sure to connect your speaker wires to the low frequency input side. This is because on the order of 70% of system power is used by the LF side: the current demanded by the HF side is much lower. That makes sense. If the majority of the current flows to the bass terminals, then the factory-supplied jumpers are MORE than sufficient for the small amount of current going to the midranges/tweeters. |
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Post by Boomzilla on Jan 17, 2016 18:39:33 GMT -5
Nevertheless, I've got all this spare wire that needs a home! LOL! There's no real benefit, but bi-wiring doesn't damage anything, either. So I'll try & see how much wire I can stuff into the casing. If nothing else, it'll be unique! Maybe then I can claim to hear mysterious and amazing sounds, attribute them to my unique speaker wires, and nobody (but youse guys) can refute my claims!  ? |
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Post by trevordj on Jan 17, 2016 19:15:52 GMT -5
If nothing else, it'll be unique! It'll be... something that's for sure. Regarding jumpers, I agree with musichead. Take a look at the amount of metal in a fuse sometime. Even a 120v 40amp fuse has just a sliver of metal running between the contacts. In comparison the amount of metal in your jumpers is at least several orders of magnitude more. The most power your mid/tweet will be able to handle before they fry is far less than the failure point of that metal jumper (they are likely around 4 ohms minimal impedance and able to handle, at most 30v or so from your amplifier, and that's being very generous, so you are looking at about 10 amps of current). If you need to prove this to yourself qualitatively, play your speaker full tilt with the jumper intact for 20min or so and then simply touch the metal jumper with your hand. If it isn't hot to the touch it is nowhere near its failure point. |
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Post by MusicHead on Jan 17, 2016 19:38:53 GMT -5
Nevertheless, I've got all this spare wire that needs a home! LOL! There's no real benefit, but bi-wiring doesn't damage anything, either. So I'll try & see how much wire I can stuff into the casing. If nothing else, it'll be unique! Maybe then I can claim to hear mysterious and amazing sounds, attribute them to my unique speaker wires, and nobody (but youse guys) can refute my claims! ? And you will be ready for your future 1kW/channel amp, feeding 4 Ohm nominal speakers, in your mansion with 100 feet walls :-) |
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Post by deltadube on Jan 17, 2016 20:51:12 GMT -5
I think I'm about to make myself (Boom's custom) bi-wire cables - Options I'm considering: WIRE: 3 parallel conductors of 14 ga. to each pair of woofer terminals + 2 parallel conductors (same ga.) to each pair of mid/tweeter terminals. Why 14 ga? Because I've got a ton of the stuff in my "spare wire" bin. This means that for a 10' long pair of wires, I'll need 100 feet of (two-conductor) wire. I think I've got that much (unless I gave it to garbulky the last time he was over). But if I don't, I can substitute two runs of 12 ga. wire for the three runs of 14 on the bass. Yet another option - use 8 ga. for the woofers & 12 for the midrange/tweeters) - single runs of each. NOW THE QUESTION: Are there any theoretical advantages or disadvantages of any of these options? TERMINATIONS: For maximum contact, I'm thinking of going with spade terminals on the amplifier end, spade terminals for the speaker woofers, and bananas for the speaker mid/tweeter terminals. NOW THE QUESTIONS: Any good reasons to do otherwise? And before anyone asks, no, I don't think that three strands of 14 ga. wire would fit into the posts as bare wires. I have the spare hardware in the junk box to terminate everything (including cable pants and nylon sheathing for the exterior of the bundled runs). Is it worth buying silver solder to do this, or should I just crimp everything for a solid connection before tinning with lead electronics solder? Thanks - Boomzilla its all over kill Boomzilla.. 18awg is plenty for 10ft unless your speakers are 2ohm.. maybe 16awg.. I have a theoretical link here... www.roger-russell.com/wire/wire.htm most excellent .. but hey I love a good looking cable and there nothing wrong with going lower it cant hurt.. also using a cl3 rated cable makes it fire safe.. that clear plastic 16awg stuff is not fire rated .. I have seen speaker cable burn... it burns fast .. cheers// |
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Post by audiosyndrome on Jan 17, 2016 23:19:19 GMT -5
Doesn't #1 imply that if ONE wire is of sufficient gauge for the power and lenght being run there is no need for bi-wiring?. Yes, exactly. All the justifications you read in the audiophile webz for bi-wiring relies on pseudoscience mumbo-jumbo. There is no legitimate electrical reason why bi-wiring does anything other than increase the effective wire gauge of the interconnect. DYohn- you mean in your opinion All the justifications........ Because in my opinion you're wrong. Biwiring is based on an exact science. That being that the magnetic fields generated by the low and high frequency currents interact with each other causing an intermodulation distortion. Biwiring may eliminate this distortion as the high and low frequency currents run in seperate cables that MUST BE SEPERATED BY AN INCH OR SO for biwiring to work. Weather you, me, or others can or cannot hear a difference is immaterial to the science. I could hear slight differences with my biwired Vandersteen 3As and my triwired Hyperion 938Ws. Russ |
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Post by knucklehead on Jan 17, 2016 23:46:52 GMT -5
Jumpers are also much shorter than any wire you are ever going to use. Again, unless they are made of utterly, abismally bad metal, what influence can an inch of metal have? Not to mention that jumpers might be thin, but they are wide. The equivalent cross section is not that small. I use a pair of Emotiva ERM-1's (with sub) in my bedroom 2 channel setup. For a long time I was getting subtle distortion from one side. My thoughts were that the receiver might be going bad so I brought it out to the living room and connected it to my L/R mains and let it play for several hours - loud and soft and in between. No distortion. Hmm. Source? Well that was from a thumb drive which I was using to play music on - flac files - the Onkyo 8050 stereo receiver decodes it. I couldn't reproduce the distortion in the living room so I went back to the speakers and decided to check the wires and overall connections for tightness. I removed the metal jumpers on all four terminals and found they were discolored. I cleaned them up with soap and water using a scotchbrite pad. Nice and shiny! No more discoloration. I put everything back together and haven't had a problem since. It bothers me that this could happen again so the fix would be to make up 4 short 14ga wires with the appropriate sized lug connectors and crimp them on. Since I use banana plugs (I must have 26 pairs or so!) on all my speaker/amp connections the lugs would not be disturbed once I tighten the screw-down speaker terminals on them. Maybe not permanent but close to it. Like a lot of things around here I just need to get a round-to-it. I lost the one my son gave me. Has anyone seen mine? It looks like this:  |
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Post by knucklehead on Jan 17, 2016 23:54:14 GMT -5
Nevertheless, I've got all this spare wire that needs a home! LOL! There's no real benefit, but bi-wiring doesn't damage anything, either. So I'll try & see how much wire I can stuff into the casing. If nothing else, it'll be unique! Maybe then I can claim to hear mysterious and amazing sounds, attribute them to my unique speaker wires, and nobody (but youse guys) can refute my claims! ? Actually that is exactly how audiophools make their ridiculous claims and get away with it. How can you disprove what someone else claims to hear? You can't. As long as the audiophool stays away from anything that smacks of DBX testing they can claim to hear radio waves beamed at earth from places far far away. And that is where you'll find the audiophool if they hear anything about a DBX testing place - they'll be far far away too. |
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Post by Boomzilla on Jan 18, 2016 0:42:41 GMT -5
Y'all miss the point - Mostly what I want is to use my flashy neon-green speaker wire jackets! LOL
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Post by trevordj on Jan 18, 2016 3:45:10 GMT -5
That being that the magnetic fields generated by the low and high frequency currents interact with each other causing an intermodulation distortion. Biwiring may eliminate this distortion as the high and low frequency currents run in seperate cables Even if the theory you propose here makes a difference, it doesn't apply to bi-wiring (or passive biamping for that matter). Full signal is sent through both speaker wires only to be separated in the speaker cabinet by the passive crossover network. The same signal is present in both speaker wires. |
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Post by vneal on Jan 18, 2016 8:57:31 GMT -5
Well it is a fact that flashy green neon jackets improved the sound. Remember when people painted the edge of cd's green? The color neon green is the most visible on the visual scale helping lost sound waves to be absorbed into the cable jacket improving the sound in neon green speaker cable jackets. This works best at night with no lights of course which can cause harsh or brighter sounds
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Post by Boomzilla on Jan 18, 2016 9:23:06 GMT -5
The sound would improve even more if I wound the neon-green cable-jackets with strands of flashing LED Christmas lights! I have scientific proof! LOL
For a small, phenomenal fee, I can make some for you, too!
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Post by copperpipe on Jan 18, 2016 9:51:11 GMT -5
Nevertheless, I've got all this spare wire that needs a home! LOL! There's no real benefit, but bi-wiring doesn't damage anything, either. So I'll try & see how much wire I can stuff into the casing. If nothing else, it'll be unique! Maybe then I can claim to hear mysterious and amazing sounds, attribute them to my unique speaker wires, and nobody (but youse guys) can refute my claims! ? Actually that is exactly how audiophools make their ridiculous claims and get away with it. How can you disprove what someone else claims to hear? You can't. As long as the audiophool stays away from anything that smacks of DBX testing they can claim to hear radio waves beamed at earth from places far far away. And that is where you'll find the audiophool if they hear anything about a DBX testing place - they'll be far far away too. That's it exactly. ANY other field (medicine, space, computers) these guys would get the book thrown at them, but somehow in audio they can make the most absurd claims but get ... upset ... when you want them to prove it. They'll spend countless hours, days even, worrying about something so incredibly negligible while ignoring that the amp / speaker / other electronics itself probably have made other compromises (due to cost or whatever) that have much more of an audible affect. |
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Post by audiosyndrome on Jan 18, 2016 11:05:16 GMT -5
That being that the magnetic fields generated by the low and high frequency currents interact with each other causing an intermodulation distortion. Biwiring may eliminate this distortion as the high and low frequency currents run in seperate cables Even if the theory you propose here makes a difference, it doesn't apply to bi-wiring (or passive biamping for that matter). Full signal is sent through both speaker wires only to be separated in the speaker cabinet by the passive crossover network. The same signal is present in both speaker wires. Absolutely wrong. Removing the jumper between the woofer terminals and tweeter terminals separates the internal crossover into two sections. Then apply Ohms Law I=E/R (or E/Z in the case of a speaker) to each of the two separated wires and you see that the currents are different in each wire. As an example, take a speaker with a first order crossover, an inductor in series with the woofer, a capacitor in series with the tweeter. The current flowing in the woofer leg is E/Z or E/ jwL. The current flowing in the high frequency leg is E/Z = E/1/jwC= EjwC. So as you can see different currents flow in each wire. At low frequencies most of the current flows in the woofer section, very little in the tweeter section . And the opposite at high frequencies. Very little current flows in the woofer, most of the current flows in the tweeter. Russ PS- w should be omega which equals 2 x pie x f. I obviously don't know how to call up the symbols for omega and pie. |
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Post by trevordj on Jan 18, 2016 11:59:39 GMT -5
Absolutely wrong. Removing the jumper between the woofer terminals and tweeter terminals separates the internal crossover into two sections. Then apply Ohms Law I=E/R (or E/Z in the case of a speaker) to each of the two separated wires and you see that the currents are different in each wire. As an example, take a speaker with a first order crossover, an inductor in series with the woofer, a capacitor in series with the tweeter. The current flowing in the woofer leg is E/Z or E/ jwL. The current flowing in the high frequency leg is E/Z = E/1/jwC= EjwC. So as you can see different currents flow in each wire. At low frequencies most of the current flows in the woofer section, very little in the tweeter section . And the opposite at high frequencies. Very little current flows in the woofer, most of the current flows in the tweeter. Russ PS- w should be omega which equals 2 x pie x f. I obviously don't know how to call up the symbols for omega and pie. I misunderstood your original post. I thought you were saying the actual frequency content of the signals was different in each wire. I think I just misread it. Of course the current is different. Since I've got your ear, can you demonstrate the quantity of the eddy current created and how this contributes to imd? Just curious. |
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Post by audiosyndrome on Jan 18, 2016 13:18:06 GMT -5
Absolutely wrong. Removing the jumper between the woofer terminals and tweeter terminals separates the internal crossover into two sections. Then apply Ohms Law I=E/R (or E/Z in the case of a speaker) to each of the two separated wires and you see that the currents are different in each wire. As an example, take a speaker with a first order crossover, an inductor in series with the woofer, a capacitor in series with the tweeter. The current flowing in the woofer leg is E/Z or E/ jwL. The current flowing in the high frequency leg is E/Z = E/1/jwC= EjwC. So as you can see different currents flow in each wire. At low frequencies most of the current flows in the woofer section, very little in the tweeter section . And the opposite at high frequencies. Very little current flows in the woofer, most of the current flows in the tweeter. Russ PS- w should be omega which equals 2 x pie x f. I obviously don't know how to call up the symbols for omega and pie. I misunderstood your original post. I thought you were saying the actual frequency content of the signals was different in each wire. I think I just misread it. Of course the current is different. Since I've got your ear, can you demonstrate the quantity of the eddy current created and how this contributes to imd? Just curious. Yes; the current is different because the frequency of the current in each wire is different. And no I can't, but I can hear it. Russ |
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Post by trevordj on Jan 18, 2016 13:43:41 GMT -5
Yes; the current is different because the frequency of the current in each wire is different. And no I can't, but I can hear it. Russ  It is impossible that the frequency content is different in each wire if the wire occurs before the crossover. The current, yes. |
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KeithL
Administrator 
Posts: 10,274
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Post by KeithL on Jan 18, 2016 14:25:33 GMT -5
Just a few random (somewhat) comments on the subject.....
1) Fatter wire is almost always better. I wouldn't go as thin as 18 gauge - even for ten feet - even though technically the resistance of ten feet of even 18 gauge wire is pretty low. Incidentally, you also have the issue that fatter wire has more surface area, and that many binding posts will allow you to tighten them more securely with fatter wire. I have also noticed that, when people compare "bi-wiring" to "not bi-wiring", they are usually failing to double up on the thickness of the single connection to compensate for the extra wire gauge with two wires, and so the lower resistance, of a double connection. To be fair when comparing bi-wiring, you should try with and without the jumpers at the speaker end, and see if you hear a difference (that way you're using the same amount of wire - just bi-wire or not).
2) Worrying about intermodulation of magnetic fields in the cable is sort of silly. Because no crossover is sharper than 18 dB/octave or so (and using a sharper one would have other unpleasant side effects), and because the same signal voltage is being sent to both wires, the tweeter is going to be receiving some small amount of the woofer's low frequency audio signal anyway. And I'm pretty sure that the effect of the amount of 50 Hz audio reaching the tweeter through it's crossover is still going to be much greater than the amount of magnetic field modulation caused by the two currents traveling through the same wire. If anything, the only part of the equation worth worrying about would be the voltage drop in the wire caused by the woofer current modulating the voltage that is driving the tweeter.... although, if the wire is at least 14 gauge or so, I can't imagine that being significant either. And, if you're really worried about the magnetic fields interacting, then you shouldn't even run the wires next to each other - yet many expensive "bi-wires" are made up of two pairs of wires in the same outer sleeve, running right next to each other.
(If you want to worry about things modulating other things, then how about the modulation of the treble itself by the bass itself? The bass coming from the woofer pushes on the front of the tweeter diaphragm, causing it to move, so the tweeter is moving while producing treble - which is modulation. And, even beyond that, the bass waves in the air are modulating the air pressure itself, and, since air pressure affects density, which affects the speed of sound in air, the bass is also modulating the treble that way.)
3) Bare wire probably makes a better connection than spade lugs - BUT, you can get gold plated spade lugs, while bare wire is usually just copper. If you're using plain wire instead of fancy stuff, it makes sense to simply cut the end 1" of the wires off once a year and re-strip them to expose fresh clean copper. (I have seen really old "speaker wire" where oxidation crept in from the ends, and the wire was oxidized for several inches; I've also seen cheap wire with clear insulation where the entire length of the wire had eventually turned green, presumably because of some serious problem - like corrosive impurities in the copper itself, or in the insulation. Of course such things should be avoided.)
4) I do find it rather humorous that some people get so excited about bi-wiring, or just insist that they hear super-subtle differences between various speaker wires, yet I've never heard of anyone using a torque wrench to properly tension their speaker binding posts, or using a micro-ohmmeter to measure the connection between the wire and the speaker to verify that the resistance of the connection is really as low as it should be. (I have to say that, of the few situations where I noticed an audible difference, it always turned out to be due to a noticeably oxidized wire, or a loose binding post, or some other factor far beyond the differences you'd measure in properly functioning wire and connections.... Perhaps people should worry more about whether their speaker terminals are tight than about which flavor of unobtainium they're made out of. Electrically, how tight your speaker terminals are, and how often you clean them, is going to make a much more significant difference than the difference between a $5 roll of speaker wire and a $10,000 set of cables. I honestly wonder how many people credit a difference to some expensive new speaker wire, when the credit really belongs to the simple fact that they have a better connection - because they re-tightened the binding posts when they installed it.)
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Post by ÈlTwo on Jan 18, 2016 14:32:32 GMT -5
Not a vacation day for you Keith  |
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