Your response has nothing to do with my comment, copper has a temperature coefficient. You seem to enjoy making insulting comments, please keep them to yourself.
And where does the temperature coefficient of copper and 200A and caution should be observed in this place? You can also be silent with this supposed clue.
Here I showed this circuit several times. But you flew so high in the clouds that you did not see or hear this. Just assuming that audio cables do not affect anything.
Last edited:
We clearly have a slight language barrier here. Copper only has a non-linearity when it is sufficiently heated by excessive current in normal use it is just a small resistance. The picture you show is of the Aurex or as Kenwood called it Sigma Drive which simply puts the cable resistance in the feedback loop to minimize the net amplifier output impedance. It has nothing to do with non-linearity, a speaker connected to a perfect 0 output impedance amplifier directly would still be non-linear.
And in what specific place do you think that this amplifier resistance is minimized, that this circuit does not affect anything?
https://audio-database.com/AUREX/amp/sc-lambda90f(11).JPG
Last edited:
Okay, I've read about compression from the voice coil heating up and increasing resistance, but not from the speaker cable heating up! I've got jumper cables out in the car, would that help ...
I recall from the previous thread a series of posts on the advantages of current-driven (or was it called "constant current?") power amplifier outputs, one of which is to would fix compression from the resistance-variation-with-temperature of the voice coil, the speaker cable and any series inductors in the crossover. I don't offhand recall any negatives of this, just that the (poor, persistent) poster was thrown under the bus.
I'm also reminded of the story of the start of Underwriters' Laboratories.
I thought it might make a pleasant change. Plus I am actually interested. It's all Bob Cordell's fault btw for putting me onto a Rickie Lee Jones track that will happily clip a 250W amp if listened to at normal levels. So I've started collecting albums that have a reported DNR with the foobar plugin of over 20 to see if I can find out what is actually going on. Eventually I might even find some music that has natural dynamics* AND is worth listening to 🙂
*Note I haven't currently a clue how much compression becomes audible so there is no stick in the ground on 'natural'. I just know a lot of stuff sounds 'flattened' to me.
Where did I say that? It's akin to a four wire resistance measurement to eliminate the resistance of the leads. There is no removal of load distortion going on here.
Vaccy et al,
Loudspeaker cable does make a measurable difference in my large size installations.
One issue I have that normal personal audio systems do not is crosstalk.
Another issue that the first Transatlantic Telegraph Cable had was limited bandwidth. Typical order of magnitude was a bandwidth of .1 Hz or so for a 3,000 mile cable.
As I see it the issue becomes one of length. Enough cable of any construction will affect the reproduction to where it is measurable.
Closer to the home use reproduction system was a system example I ran across. The music department of a local university had someone donate a ludicrously expensive complete high end system complete down to the cable. The reproduced music sounded worse than the modest priced system it replaced. An examination showed it was wired with very much too long quite expensive heavy gauge cable. Reducing the cable to the much shorter length required made an amazing difference. Obviously the loudspeaker load impedance varied with frequency. So a cable length having too much resistance changed the frequency response of the entire system. Very much a basic issue. Note that the impedance changing with frequency is not considered a nonlinear load.
In larger systems I can look at the loudspeaker impedance during use. It comes as no surprise the impedance rises as the units heat up in use. Practical limits are that the impedance may double at still safe levels of power. If the impedance rises above doubling, permanent shifts in the operation is a typical result. (Also known as damaging the loudspeaker.)
The issue for typical users here is at what length do loudspeaker cables matter. Certainly this is affected by the loudspeaker load, to usually a lesser extent the amplifier's output behavior and of course the circuit theory parameters of the connecting cable.
For my use I have custom made cable. Certain custom bits do not really add to the cost, other simple things such as changing the twists per foot really are expensive. Then there is the National Electrical Code requirements, such as wire gauge and permissible insulations. No cost but very important considerations are things like wire colors!
Some folks seem to think the color of the insulation affects the performance. I can tell you that is completely true under certain conditions!!!! Yes the sound will be quite different if the colors selected are wrong and the installing electrician is red-green color blind!
Loudspeaker cable does make a measurable difference in my large size installations.
One issue I have that normal personal audio systems do not is crosstalk.
Another issue that the first Transatlantic Telegraph Cable had was limited bandwidth. Typical order of magnitude was a bandwidth of .1 Hz or so for a 3,000 mile cable.
As I see it the issue becomes one of length. Enough cable of any construction will affect the reproduction to where it is measurable.
Closer to the home use reproduction system was a system example I ran across. The music department of a local university had someone donate a ludicrously expensive complete high end system complete down to the cable. The reproduced music sounded worse than the modest priced system it replaced. An examination showed it was wired with very much too long quite expensive heavy gauge cable. Reducing the cable to the much shorter length required made an amazing difference. Obviously the loudspeaker load impedance varied with frequency. So a cable length having too much resistance changed the frequency response of the entire system. Very much a basic issue. Note that the impedance changing with frequency is not considered a nonlinear load.
In larger systems I can look at the loudspeaker impedance during use. It comes as no surprise the impedance rises as the units heat up in use. Practical limits are that the impedance may double at still safe levels of power. If the impedance rises above doubling, permanent shifts in the operation is a typical result. (Also known as damaging the loudspeaker.)
The issue for typical users here is at what length do loudspeaker cables matter. Certainly this is affected by the loudspeaker load, to usually a lesser extent the amplifier's output behavior and of course the circuit theory parameters of the connecting cable.
For my use I have custom made cable. Certain custom bits do not really add to the cost, other simple things such as changing the twists per foot really are expensive. Then there is the National Electrical Code requirements, such as wire gauge and permissible insulations. No cost but very important considerations are things like wire colors!
Some folks seem to think the color of the insulation affects the performance. I can tell you that is completely true under certain conditions!!!! Yes the sound will be quite different if the colors selected are wrong and the installing electrician is red-green color blind!
Last edited:
Of course, because impedance (not characteristic impedance but actual L/C/R) is a function of length. The obvious advice for home users is to minimize speaker cable length, and the easiest way to do that is active speakers.
I'd think the easiest way is put the amplifier behind the speaker and run a short speaker cable. Perhaps one of the problems with high-dollar cables is no one wants to cut them down to the appropriate length.
On the other hand, I've read where active speakers haven't made a lot of inroads into audiophile land because "they" like to mix'n'match amps and speakers, which requires the use of passive-crossover speakers.
But no - why not have an active speaker with a big (50 watt or so) 8 ohm resistor at its input which then goes to the usual active electronics and such ... get the SET amp sound with louder speakers!
On the other hand, I've read where active speakers haven't made a lot of inroads into audiophile land because "they" like to mix'n'match amps and speakers, which requires the use of passive-crossover speakers.
But no - why not have an active speaker with a big (50 watt or so) 8 ohm resistor at its input which then goes to the usual active electronics and such ... get the SET amp sound with louder speakers!
I guess, speaker's sensitivity plays a role too... 🙂
From the old days, Ricky Lee Jones ones did an EP including a cover of "Under the Boardwalk" which has some of the natural dynamics.
and Joe Jackson's "Body and Soul" (CD from 1984) has some as well.
Iirc, I've linked in previous discussions a paper about the underlying metric used to calculate DR numbers, it is different from technical metrics like the crest factor as it relies on the loudness perceived by humans. Average perceived loudness to peak perceived loudness.