Bi-Wiring Speakers

Redfred and bwire appreciate the comments , this gives me something to ponder, may try the computer's UPS, see what happens.

I'll let you know.

Ratty

And on a related note: the TV that is now connected to the sound system has an intermittent visual problem.

If as formerly indicated this is deemed an upstream electrical interference a simple remedy maybe use of a rectifying UPS; in coming A/C is converted to D/C and then rectified as clean A/C.

Twisted stranded speaker wires are preferred over solid due impedance encountered in high-end equipment over 10ohm.

The skin effect proposed as noticeable by some esoteric audio cable snake oil representatives is pure hogwash. Audio frequencies and cable lengths found in any home preclude any skin effect phenomena. Now if you have a separate A/D chassis to convert your digital audio to analog signals, you can with an oscilloscope see the skin effect on the digital signal. But this is an anticipated effect that the signal source and receiver of the digital stream are designed to ignore. So once your A/D decodes these signals, no net skin effect exists.

Now as far as the number of strands for the same gauge wire question, you have an interesting insight that less strands will corrode less. But most audio cable failures I've found come from metal fatigue effects from predominantly low frequency mechanical coupling flexing the cable. Unless this is a musician's instrument to amplifier cable, no special high flex cabling be necessary. But I would be hesitant to use solid conductor wire on anything but a very permanent, fixed installation like wall recessed speakers.

Now for the possible voltages and currents, with the nominal eight ohm speaker and a 100 watt amplifier on one channel, the largest RMS voltage one will expect with this size amplifier would be about 28 V_rms. The largest RMS current will be about 3.5 A_rms. But of course the actual levels present will dynamically change with the music and your volume preference.

As far as shielding, only the input cables need to be shielded to attenuate the ever present power hum. The amplifier to speaker connection does not care about coupled interference due to the very low impedance of the speaker and the amplifier's output impedance.

Lastly, interference removal of any system is always a difficult problem to tackle. Since you have an intermittent problem, the difficulty to solve it grows to a near impossibility. First, if this TV is the only TV in your house that shows this interference then buying a new TV will be easier than trying to fix it. If all TVs in your house show this interference, the source of the interference can be anywhere upstream of your home.

Have been following this thread and still have a question about the wires from the receiver to the speakers.

let me see if I can phrase these questions correctly;

If the output from the amp to the speaker is a dc current, wouldn't the optimum conductor be a solid core wire?

There is no skin effect as in ac, correct?

Reducing the number of strands should reduce the surface to surface contact areas at the speaker connections, reducing the total area where potential corrosion could develop, yes/no?

If the speaker is not powered, I'm assuming the signal from the amp modulates the sound produced by the speaker by varying the amperage; what range of voltage and amps would one be observing? I know the capacity is described in watts, yes, I have heard of Ohm's Law, but I am a complete electrical/electronics layman and have never calculated anything with it.

Is there an advantage to shielding in order to reduce RF & EMF noise input?

And on a related note: the TV that is now connected to the sound system has an intermittent visual problem. Occasionally it develops a faint line that crawls slowly from bottom to top. I thought it was RF interference from a lamp ballast or electronic dimmer, but it occasionally returns even when there is no power to the suspect devices. Possibly power pole transformer or street lighting? Would some kind of filter/choke thingie help?

The sound systems I have are adequate for my needs, not expensive, but I would like to get the optimum performance out of them.

14 AWG zip cord from Ace Hardware is fine and fancy.

It was posted somewhere here before, where a double blind test between a high quality speaker wire (Monster Cable) and soldered together coat hangers was performed and the test subjects could not determine the difference.

Monster Cables vs. Coat Hangers

Warning: Don't bother trying this with plastic coat hangers. Too hard to solder.

I went down that road about 10 years ago, spent huge ammounts on Players, amps speakers, cables & interconnects etc. eventually ended up with Yamaha flagship dts amp which I still have today, I tried the bi wire thing as I was advised treble and base needed different types of cable...Naa! A Good quality low capacitance cable generally does the trick. Also do get good quality interconnects.

Thank you all for re affirming what I thought to be true, but wanted other gearheads to assure me I wasnt going to miss out on a way to improve my home theatre. I really couldnt get my head around how this could possibly improve the performance.

I think I will take the money I was going to use on the new wire and buy a case of beer and the Dave Matthews/Tim reynolds Blu Ray.

Cheers

TGB

Don't forget the tin coated gold wire for magnetic shielding. Comes gift wrapped! Just like the $200 hdmi cables!

Oh, well it's pretty humid in Florida, so that dry stuff can go right by us. :)

I do not disagree though my dry humor may have escaped you; bi wiring is futile unless prepping for a result.

I like to use horns and I like the amp to be integral.

Good link! That is correct if you are using a 1st order crossover. Most are second order L-R.

As I stated, Most (if not all) of the passive crossovers I have seen, worked with, or designed, did not use compensation on tweeters in the real world.

You wrote, "Now maybe one audiophile prefers the lack of noticeable even harmonic distortion that vacuum tubes produce..."

Vacuum tubes actually produce a lack of odd harmonics, which was my point.

Otto Zobel designed an approach to filter design that permits matching any complex impedance to produce any desired load impedance. (It can and does far more but for this discussion, I'll leave it at that.) Now in many audiophile circles, a Zobel network compensates solely for the rise in impedance many woofers produce as the frequency increases. But this is actually just one use and only one configuration of a Zobel network. In passive crossover networks Zobel's methods can be used to normalize the impedance of any part of a driver. Notice in particular section 3.1.2 on mid-range and tweeter of the Elliot Sound Products web page I linked. By normalizing the resonant impedance peak of a driver, he says ... if you are using a crossover network with a slow rolloff, or the frequency is too close to the resonant frequency of the driver. People do permit at times frequencies close to the speaker's resonance. This impedance matching network is a different Zobel network.

Permitting too much energy at speaker resonance can produce very ugly sounds. But if done properly, particularly by passively dampening this so that all frequencies are over damped then even this can be done. Now frequencies at and below resonance must occur only at only low current levels for the voice coil will quickly reach its excursion limit. So the roll off network typically attenuates frequencies at resonance sufficiently so that these non-linear distortions do not occur. But since the driver more efficiently couples power to the air as one approaches resonance, some people do do this.

Oh and the last time I noticed, 2 was considered an even number.

There is no sense selling snake oil to people asking legitimate questions. Bi-Wiring is snake oil, pure and simple.

As far as your comments go:

First, tubes (or valves as they are commonly referred to in Europe) tend to produce 2nd order harmonics, not third, when overdriven. Ideally, no amp should be overdriven when reproducing HiFi music. The exception might be a guitar amp where distortion is part of the sound that the musician is seeking. Distortion that is absent of odd-order harmonics is psychologically more pleasing than amps that produce both even and odd or just odd order harmonics.

A HiFi reproduction amplifier should ideally be a wire with gain. Vacuum tube amplifiers can approach this almost as well as a solid state amp. I say almost because solid state does this with the ability to bring higher damping factors, greater power, and longer and more consistent operation than a valve amp. That being said, a high quality valve amp and a high quality solid state amp, side-by-side, in a double-blind test would be indistinguishable from each other. The idea that valves add some magic to the sound is just bull. The only advantage would be if the music is overdriven and the distortion components from a valve amp would be less objectionable, but you should never get to that point anyway.

Second, Zobel networks are designed to alter the apparent impedance of a driver so that the passive crossover can function better. Remember, a passive crossover is an RC network and the driver is part of that network. Drivers do not have a flat impedance curve across their working frequency, so an RC filter will not behave in the desired way if the non-linear impedance of the driver is not accounted for.

The Zobel network is typically not applied to a tweeter (at least I have never heard of one being used in that way) and there is no reason to operate a tweeter anywhere near its resonance point because cone break up and distortion are a problem long before you get down to that point on the tweeter's spectrum. The general rule of thumb when selecting a crossover point is about two octaves above resonance.

Zobel networks should be removed along with the passive crossover when bi-amping since they are designed to aid a passive crossover. Today's amps can easily manage the varying impedances of drivers and in particular, current dumping amps like the Quad 909 have no issues with driver impedance. The Zobel would simply neutralize one of the important points of bi-amping by rendering the amp's damping factor useless.

Who said anything about making sense?

Any way that a person wants to play with their toys makes sense to the only one that matters, the owner of the toys.

Now maybe one audiophile prefers the lack of noticeable even harmonic distortion that vacuum tubes produce for the high frequencies but still wants the high current power of a BJT. So the 25W/ channel vacuum tube amplifier handles the highs while the 150W/ channel amplifier drives the woofer. This individual also wants the tweeter to handle more midrange than the original speaker manufacturer choose. So to prevent possible tweeter damage when driving frequencies close to the tweeter's resonance, the owner designs a zobel parameter impedance matching network to protect the tweeter from these frequencies while also permitting lower frequency excursions. This technique that permits driving closer to the resonance of a speaker can only be done with a passive crossover.

Will this provide a real sonic difference? Not to my ears anymore. But this is not my set of toys.

I agree completly. GA to ya.

Maybe not. Bi-amping has greater benefits with respect to intermodulation distortion and phase coherency than it does with frequency response.

Unless your hearing is so severely degraded you probably would be able to pick out the differences under the right conditions.

"whistles of tinia that middle age has granted me"

I'm with you. That 10 KHz ring in the ears makes bi-wiring/bi-amping or just about bi-anything a useless exercise for me.

Huh? has become the most uttered phrase around my house.

There is no real sense in bi-amping using passive crossovers. It puts you back to square one with one amp and a passive crossover. The only advantage might be in higher available power with multiple amps, but that is it.

Bi-amping (or tri-amping) with an active crossover is another story with very tangible benefits.

I assume that when you stated, "Bi wiring with an active crossover will permit this type of flexibility", that you meant Bi-Amping. Running redundant wires, whether you are Bi-Amping or Bi-Wiring, is a useless exercise.

Not all but some bi-wire speakers permit by passing the crossover network. In this configuration (the only one that makes sense to me) you must provide your own crossover to stear the highs to the tweeter and the lows to the woofer. The crossover can be either passive after one or two amplifiers or active before two amplifiers. This permits endless tweaking of the crossover frequency, number of poles (aka rolloff) to suit your preference. Some people prefer the sonic quality of one amplifier for low frequencies and another for the high frequencies. Bi wiring with an active crossover will permit this type of flexibility. (To just double up the wires from one amplifier to the same crossover to separate the frequencies to your multiple drivers is just silly.) At one time I felt that my ears could appreciate these subtle nuances. But as I sit here typing, I can still hear the ever present whistles of tinia that middle age has granted me. I'm now ambivalent about this speaker wiring configuration and on the fly flexibility for the user of a speaker system. This additional tweaking capability promotes the listener to listen to the speakers and not the music. For the speaker system designer though this is a very useful configuration for prototype crossover development.

Real audiophiles do not wire speakers. Real audiophiles use only solid gold bus bars of at least 1/4" x 1/4" (6mm x 6mm) cross section. All connections must be welded: screw terminals, RCA connectors and especially spring loaded terminals are not permitted. Voice coil wires or ribbons must also be of 24k gold.

It is absolutely essential to use a premium power cord to supply the amplifiers, (don't even think about touching any of the cheap $500 ones) assuming that you have already wired a direct connection to the power plant with gold wire, and are using audiophile grade transformers feeding your house (and your house alone). The prudent audiophile will create his own power on site to ensure that there are no frequency shifts or voltage fluctuations in the power line. (I am assuming every audiophile knows to use only solid gold 6 gauge wire to all outlets in the home.)

Just a few precautions like these can help ensure your pleasure... when listening to those great recordings made in professional studios with hardly a gold-plated connection in sight, and with ordinary wiring to their monitor speakers.

My experience. Read on a website about the wires from tuner to speakers, the writer was experimenting with thin wire, don't remember size, 18Ga.?

He had used very pure silver wire, 99.99% pure, not sterling, and an appropriate size tubing as insulator. Kind of a pain slipping the tubing on the soft silver wire and somewhat pricey, still cheaper than the high-end store bought cables.

He reported excellent sound quality.

I'm cheap, so I took twisted pairs from some cat5 that I had.hooked it up and was pleasantly surprised at the sound quality. Much better than the hodge-podge, zip cord set-up I previously used.

Now, he did say that you can use copper, but one of the advantages of the silver was the silver oxide is conductive, apparently the copper oxide isn't, could be an issue at the connections.

Also it is important to have the lengths of the wires the same, regardless of the actual distance.

Try googling component cables or audio cables.

Good luck

Absolutely, bi-wiring is an excellent way to get started in listening perfection then when you're ready to advance and with the wiring in place up grade to bi-amping gracefully and the difference will in no way be subtle.

Many as I do prefer to dedicate frequencies sent to the amp so providing a cross-over upstream of the amp eliminates inconsistencies down stream. Have individual amplification for each transducer clear sound no mud.

I did it only because I had a bunch of speaker wire laying around. No audible difference whatsoever.

Here is another site with speaker wire information.

http://www.roger-russell.com/wire/wire.htm

HTH...

I hope you'll be using gold wire instead of that crappy copper kind.

Don't waste your time. If your current wiring/connectors/terminations are all properly sized and crimped/soldered/attached you will be fine. You can only shove so much power into the voice coil anyway before the thermal resistance of the wire gets so high that it burns out.

But, that's just my opinion.

Don't waste your time and money. It is an absolute farce and the electronics industry is simply perpetuating it by offering terminals on speakers that support it.

There is absolutely no scientific or physics data that can support the biwiring claim.

As long as the speaker cable is correctly sized for the application you will be fine.

Think of it, what possible advantage can be achieved by doing this? Both wires still cary the same signal. The inductance, resistance, and capacitance of the wire is near zero and far less than any crossover inside the cabinet.

Bi-Amping is another story and tangible benefits can be realized by going to an active crossover, but that comes with its own set of issues.

To be honest, I have never heard the term. Here is what my buddy Wiki has to say:

Opponents of bi-wiring argue that the two ways of making connections are equivalent. This has led some to sarcastically refer to the practice as "buy-wiring", implying it is nothing more than a marketing gimmick for expensive speaker wire.

Wiki also has a link to this clearly titled piece, The Ten Biggest Lies in Audio:

http://www.theaudiocritic.com/downloads/article_1.pdf