If you shorted one end of the cable and made an adapter that put a 10K resistor in series with the other end you could just plug the cable into an AC outlet.
But, keep in mind, guys, that all electrons in the universe are EXACTLY alike. And, electric current does not change metal. You can run current thru copper for a billion years it will not change it. There just isn't anything in the copper to change.
The psychoacoustic effect of almost always hearing a difference is very real. Cable conditioners are proof of this. |
Josler - Leather cables are good for country western music. |
Ontario - There is more to my post than sarcasm. Stirring water in a swimming pool and expecting that to change the water's characteristics is a fair analogy to sloshing electrons back and forth in a wire and expecting that to change the electron's (or wire's) characteristics.
Oddly, it seems that the more preposterous the belief, the less likely an explanation of why it is preposterous will be useful. |
Miracle Products:
For swimming pool owners, we have a "water condition". After filling your pool, it stirs up the water for several hours. You would be amazed at how the much smoother it is after being broken in. It relaxes the water molecules.
For your car: Don't use oil that hasn't been broken in! THis new device subjects the oil to real conditions for several hours before your oil change. You would be amazed at how much less grainy the oil is.
Got stiff, lazy, or jerky electrons in your cables? Our cable conditioner will get those darn electrons whipped into shape in no time. Our condition has several hours of specially designed "music for electrons". This special computer generated music will energize reluctant electrons and remind them to behave properly. |
Sean - My opinion, for what it is worth, is that most people here are probably better listeners than I am. I would not want to be in a listening contest with anyone here where we were trying to distinquish between signals with measureable differences. I am pretty sure the folks here have ears that are as good as ears get.
I would not hesitate, however, to bet a huge amount of money that, in a true double blind test, no one could tell if a cable had been "conditioned".
If it really would mean something to you I will try to dig up evidence that electrical signals won't change the property of metals. I hear over and over again the argument that science doesn't know everything therefore what one hears is real. This makes it pointless to give scientific evidence. |
KD - Let say that we run a 10 volt square wave, that's 10 volts RMS. Say cables have .2 ohms resistance and the load is 10K. Current is E/R or 10/10000 = 1/1000 amp. Power (watts) is current squared times resistance so Watts = 1/1000 X 1/1000 *.2 =1/5000000 or one five millionth of a watt.... I think we can rule out heat as a factor.
If this doesn't make any sense, here's another way to look at it. If electricity cost 10 cents a kilowatt/hour, you will have to leave a cable on the conditioner for 57,000 years to get 1 cent worth of electricity heating the cable. |
Shame on you 702! There you go getting scientific again. You just won't behave yourself. Just because you are an electrical engineer who works in audio and nearly everyone else who posts here doesn't even understand electricity, doesn't give you the right to go making stupid anti-group statements. Right on JD, I'm with you pal. |
I agree with you 110% Albert. I am trying my best to fit in. I have expressed none of my opinions about HIFI stuff for days. Perhaps you could provide me with a list of things that are appropriate for me to say. |
doug - I wasn't jesting. I was just musing. I'm not up to date on amplifier designs. So, it is interesting to hear that some of what I mentioned has been tried. There was an amplifier some time ago called "Ampzilla". It sounded different. The trick that amp's designer had used was to set the damping factor to one. Typically, this will increase the low end. With the advent of cheap powerful processors there maybe a lot of interesting possibilities. The processor looking at the music and dynamically fiddling with the an amplifiers characteristics. I'm gonna think about this a little. |
I have a question for the type of engineer to whom Sean is giving Kudos.... When you have designed an amplifier that has very low harmonic and intermodulation distortion, no transient imtermodulation distortion, low noise, stable under all loads, flat frequency response, low phase shift, in other words when all the specs are great; what kinds of things do you think about changing when you decide that it doesn't sound very good? |
Sean - If I were a designer with a design that was as technically perfect as the state of the art would allow and yet some audiophiles complained that it "wasn't right" or wasn't musical or wasn't lifelike here's what I would think about trying.
First, I would consider injecting noise into the output. Now, no one likes noise during the quite passages so I would make it a smart noise injector that varied its output with with volumn and perhaps energy in the high frequencies. The noise spectrum would probably not have lower frequencies - one would have to experiment. The circuit would recognize testing conditions and not operate. I suspect that noise gives music an airy lifelike quality that many like.
Next, I would lower the damping factor. As the damping factor lowers the amplifier begins to get involved in the music. Lower damping factor may or may not have a pleasant effect, so, a damping factor control knob could be an attractive feature. From a marketing standpoint I would give it a name something like "Voicing".
I would also experiment with increased harmonic distortion. I don't know if it is possible to increase lower harmonic distortion without increasing itermodulation distortion. IM creates unnatural frequencies and is always unpleasant. Harmonic distortion on the other hand is what music is all about. All musical instruments owe their sonic character to harmonic distortion of the fundamental. Just the right kind of harmonic distortion could, I suppose, make an amplifier seem more musical. |
frap - I enjoyed hearing your take on the Ampzilla. I'm not a EE either but I have had the luxury of working with several. Here are a few things I've learned that relate to power supplies, voltage sources and damping factors. You may already be familiar with this.
It is a high damping factor that makes an amp a true voltage source. Damping factor is the measurement of change in output voltage as load impedance varies. In the case of the Ampzilla as the speaker impedance climbed from say 8 ohms to possibly 30 ohms at resonance (closed box), the output voltage of the amp increased. You got to have more bass without feeling guilty about using the tone controls :-) Naturally there is a price to be paid, two actually. One, the speaker impedance doesn't always change in a favorable way. This is probably why the electrostats sounded bad. The amp is changing the frequency response based upon speaker impedance. No one will argue that even tiny changes in frequency response are not easily detected. Second, when a dynamic driver overshoots or rings (as they all do) they generate a correction signal that acts like a shock absorber to dampen the overshoot. If an amp has a low damping factor much of this signal is lost. This may be the whoopyness you refer to. If you want to fool around and see what your amp would sound like with a lower damping factor, hook you speakers up with 24 or 27 gauge wire. Even that may not get the DF as low as the Ampzilla.
As I understand it, in SS amps stiff power supplies are a benefit to the designer but not to the listener. Suppose you want to get all the power you can from your output transistors. In that case you design a rock solid (expensive) power supply that parks the power supply voltage near the maximum voltage the output transistors can handle. As transistors got better it became possible to have a higher voltage spongy (less expensive) power supply. It would sag and deliver the rated power of the amp and under music conditions operate at higer voltages and deliver greater power to the speakers than a stiff supply of the same RMS rating. I'm not sure but it may be that this technique doesn't work so well with tubes. I think the tubes are biased to operate at a particular voltage and to have the power supply bouncing around one or two hundred volts could screw up the amps performance. |
Sean - I think you are right that the output voltage of the amp will be more regulated with the small wire. However, I believe the voltage at the speaker terminals will not. Instead of small wire just imagine that an 8 ohm speaker has an 8 ohm resistor in series with it. Now half the amplifiers output voltage will be dropped across the speaker. AS the output impedance of the speaker falls less voltage is dropped across the speaker. As the speaker impedance rises the voltage across the speaker increases. The speaker is no longer connected to a voltage source. As seen by the speaker the 8 ohm resistor trashes the damping factor of the amp.
Low impedance loads are a problem for all amps that are not designed for them. Even springing power supplies optimized for 8 ohms will deliver enough current to smoke output devices if the impedance falls low enough. The designer either has to use more output devices and drivers or provide an effective protection circuit that limits the current vs. time the output sees.
Frap - I didn't mention the connection between damping factor and feedback. Basically, the more feedback the higher the damping factor. SS amps have higher damping factors and lower distortion because more feedback can be used. It is difficult to wrap much feedback around a tube amp because of the output transformer. Output transformers are a designer's nightmare. One of the transformer's problems is the unavoidably large phase shift at low frequencies. This will turn negative feedback into positive feedback if very much is used. |
Sean - I used the 8 ohms just to make the example easier to think about. I'm not sure but a damping factor of one may be similar to the results with an 8 ohm resistor. You won't get any naysaying from me about phenomena that can alter the frequency response. |
Sean - I believe our ears are very sensitive to changes in frequency response. If something can be shown to effect frequency response it is a valid subject, as, of course, are many others. What I don't believe that many audiogoners do, is that there is something intrinsic in the molecular structure of the metal itself that alters the sound. It's that "silver has a laid back sound" kind of talk that drives me nuts. (People seem to not undertand that it is an electrical and not a sound signal traveling the wire). Since cable manufactures have no explanations for why one cable sounds better than another, they promote psuedo scientific explanations. I have an email from a manufacturer with just this kind of nonsense in it.
While I am ranting, let me tell you a an experience I am having with my new B&W Nautilus speakers. I hooked them up and got ready for something wonderful to happen. They sounded so bad to me I thought, hmmmm I must have gotten them out of phase. Wouldn't be the first time. I checked. Nope not out of phase. So I listened for a while and well the accuracy seemed very good. I listen for a few days and they sounded better but I'm still troubled. So I check the phase with a battery. Yep, they are in phase, at least the woofers. It's a couple of weeks now and they seem to have some bass now, it seemed totally absent at first. They are used speakers so "burn in" isn't involved.
Have I discovered a new phenomenon?... Speakers have to get used to their new suroundings before they begin to sound OK.... Or is it perhaps that the complicated, imperfect blob of protoplasm that I am is changing and the speakers are performing exactly the same as they did when first connected. |
