Ryder, The stream of information is not AC and not analagous to the voltage information before encoding into digital, i.e. numbers. The numbers (information) are carryied to the next stage and then decoded back into an analagous varying voltage + or - and amplified to drive the speakers with AC current.
Bob P. |
Fatparrot, I'll take the mention of lawyer as a compliment and not the insult that some might!
That 'technicality' as you put it, however, is a very important one and the biggest stumbling block for those who might want to convince others that directionality in any device makes any difference when the circuit in which they change the direction handles alternating current.
Respectfully, Bob P. |
My last word on this subject, which might cause more discussion!!
Electrons don't travel down cables like water through a pipe. They are transferred from one atom in the conductor to another, somewhat like pressure in a hydraulic line is transferred. If one injects 10 electrons (applies a voltage at one end of a circuit) then the 10 electrons displace 10 electrons in the first conductor atoms and those electrons displace 10 electrons in the next atoms etc. The original 10 electrons don't appear at the end of the circuit as some would believe. Depending on how the electron transfer is 'impeded', a different quantity of electrons is transfered to the final element for the same voltage. Thus if the final element and conductor offer a high impedence the current can indeed be very small, but the voltage at the final element still be sufficient for that element to get the 'message' (signal) and do its thing, amplify for example.
Salut, Bob P. |
Aball, you are the one who first stated that the arrows were in the direction of the current! Surely, as an EE, you didn't mean that, but meant the direction of the signal.
As for the shield concept indicating the direction of the cable, well we covered that.
However, it is good to finally get an EE to set the record straight on direction of current in an AC carrying circuit.
Bob P. |
Unless a cable is shielded and one wishs to know a which end the ground (shield)should be connected, directionality in cables carrying alternating current (which speaker cables do) is a marketing feature. Same goes for directionality of fuses in ac carrying circuits. |
Ryder and Fatparrot, how do you reconcile your statements that the current flows in one direction with the fact that the current actually reverses its flow continuously and variably from 20 to 20000 times a second.
Bob P. |
Ryder, you are talking about a different 'animal' with digital cables, since they do not carry AC signals but a stream of information to the next stage. There might be a difference in the cables' capabilities depending on direction.
As for hearing a difference in AC conducting cable, such as speaker cables, I am not disputing whether one hears a difference, but the 'reasons' given for the perceived differences, which all have to do with the 'direction of the signal or current in speaker cables, when there is NO direction for AC currents.
respectfully, Bob P. |
Carl, all signals in analogue are AC and therefore non directional. Circuits containing capacitors and coils cannot function on DC, they need the current to alternate at different frequencies to do their jobs.
The ouputs from digital device are simply a series of numbers that are decoded into an analagous AC signal to be amplified before being used at the speaker.
I am not an EE (I am a Chemical Engineer, actually), but have had an interest in this hobby for over 40 years and looked over many a circuit diagrams and can assure you that analogue circuits indeed carry Alternating Current, the frequency varying, of course, according to the signal being carried, thus the term Analagous.
Respectfully, Bob P. |
'If analog audio is AC, then doesn't that also defeat the purpose of direcional arrows on interconnects as well as speaker cables?'
In a nutshell, yes! BUT, the arrows (if these exist) could indicate where the shield is connected, usually at the preamp, but should always be a common place. Therefore, in a typical setup, the arrows on the cables from a turntable would point towards the pre-amp and the arrows for the cable to the power amp would point to the preamp also, which would be counter intuitive to the myth of current direction, i.e. to wards the power amp. |
'Before this I had known that there must be some current to transport those bits(information) to the next stage.'
There is current to transport the information and it is DC. The signal is essentially varying voltage representing the numbers and these stream in at a fixed rate. The current is extremely small and in one direction, which might explain why direction might count for digital transfer of info.
'Your argument is that AC is non-directional. If that's the case, how do we explain on the findings by Robert Harley in Stereophile? My logic is simple. If what he wrote is true, then this will apply to speaker cable as well. By the way, it's AC current in speaker cables am I right?'
I haven't read the article, but if he is referring to the digital cables then we have established that perhaps direction does matter with DC.
All explanations that have to do with direction of current on cables carrying alternating current stand on very shaky ground, especially for non shielded cables.
'It's interesting to note of Russ Andrews claim of having verified the benefits of cable directionality with their engineers using advanced equipment and technology, but unfortunately didn't provide any technical evidence to back that up.'
I guess they feel that we wouldn't understand the sophistry?
Respectfully, Bob P. |
