Well, the whole idea behind the DBS system is to bias the dielectric, not the conductors.
se
USB and other digital cables
While I can understand what might go wrong in a digital cable (noise especially) most don't seem to suffer irreparable harm.
For example. In a recent test I was able to make bit perfect recordings of complex music via USB and SPDIF. Signal flow thus: USB cable->Converter->Coax cable->Converter->USB cable. No fancy cables, except maybe the Canare coax.
If there were any errors along the way, something fixed them. So the end result was perfect, bit perfect.
While I can understand what might go wrong in a digital cable (noise especially) most don't seem to suffer irreparable harm.
For example. In a recent test I was able to make bit perfect recordings of complex music via USB and SPDIF. Signal flow thus: USB cable->Converter->Coax cable->Converter->USB cable. No fancy cables, except maybe the Canare coax.
If there were any errors along the way, something fixed them. So the end result was perfect, bit perfect.
I meant the electrostatic force, it's attractive for either polarity. Imagine an unbiased electrostatic speaker.
Dielectric bias
And Steve, you already got to the kernel of the issue; is there a non-linearity at the "zero" crossing that this bias eliminates?
Quite frankly, this biasing is done every day with normal phantom powered condenser microphone channels. The preamp supplies a constant 48 volt bias between pin 1 and 2+3. SO........ will we now hear people attributing a difference or improvement in the sound of condenser microphones over dynamic mics due to this dielectric biasing? Maybe 48 volts isn't enough to bias the cable non-linearity? You see where this could lead.
If there is a non-linearity to the cable dielectric, then all test equipment cables would show the phenomenon in all measurements to one degree or another, so we would never be able to see past that distortion.
Really, the issue that needs to be settled (IMHO it has been debunked already) is the presence of any cable non-linearity at the zero crossing.
Howard Hoyt
CE - WXYC FM 89.3
Chapel Hill, NC
www.wxyc.org
1st on the Internet
And Steve, you already got to the kernel of the issue; is there a non-linearity at the "zero" crossing that this bias eliminates?
Quite frankly, this biasing is done every day with normal phantom powered condenser microphone channels. The preamp supplies a constant 48 volt bias between pin 1 and 2+3. SO........ will we now hear people attributing a difference or improvement in the sound of condenser microphones over dynamic mics due to this dielectric biasing? Maybe 48 volts isn't enough to bias the cable non-linearity? You see where this could lead.
If there is a non-linearity to the cable dielectric, then all test equipment cables would show the phenomenon in all measurements to one degree or another, so we would never be able to see past that distortion.
Really, the issue that needs to be settled (IMHO it has been debunked already) is the presence of any cable non-linearity at the zero crossing.
Howard Hoyt
CE - WXYC FM 89.3
Chapel Hill, NC
www.wxyc.org
1st on the Internet
The presumed diode effect is easy to disprove. If it existed, then THD measurements at very low signal levels would be high and rise as signal level is decreased just the way it does for crossover notch distortion in class AB amplifiers that are not properly biased. I have never heard that such distortion has been reported for cables.
A.J. van den Hul believes it is there. Don't ask me for his analysis though.
A.J. van den Hul: Going Dutch Page 5 | Stereophile.com
search in page for 'crossover'
A.J. van den Hul: Going Dutch Page 5 | Stereophile.com
search in page for 'crossover'
He's talking about "diodes" in the wire itself rather than the dielectric. This is the reason he gives to justify his carbon fiber "sparkplug wires."
This seems to stem from the notion that there is copper oxide between the copper grains in the wire and as everybody knows, they make diodes using copper oxide.
But to make a copper oxide diode, you need to go from copper, to copper oxide, to something other than copper (often lead). So the notion is a bit misplaced.
But hey, it scares the bejeezuz out of people and makes for good marketing literature.
se
I think you've hit the nail on the head, Howard. That's why those old tube mics sound so good. It's that high voltage from the PSU running thru the cables - they are beautifully polarized.
Wouldn't going from copper to copper oxide to copper give you two back-to-back diodes?
If normal copper wire was full of micro-diodes with crossover distortion then this would create third-order distortion. It is possible to make radio receivers with a third-order spurious free dynamic range of 100dB. This means that ordinary copper is at least somewhat better than that. Ordinary wire has a much better dynamic range than CD, LP or FM radio. A similar argument applies to cable insulation. You would need to come up with a mechanism which only affects audio, not radio. Possible, but unlikely.
Don't know for sure, but I wouldn't think so. I mean, if it takes copper/copper oxide/lead to make a diode, then it seems you'd have to have copper/copper oxide/lead/copper oxide/copper to make a pair of back to back diodes.
Perhaps SY can shed some light on this.
se
oxygen is intentionally included in "tough pitch" copper commonly used in wire to form insoluble oxides with contaminants - which, along with Cu2O, precipitate out as discrete particles - not uniform films spanning the wire diameter or even crystal faces – although they are concentrated at the crystal interfaces
as discrete particles they are completely surrounded (== shorted out) by bulk copper - "large" particle size mean is < 10 um dia
as discrete particles they are completely surrounded (== shorted out) by bulk copper - "large" particle size mean is < 10 um dia
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You beat me to it, the fact that copper with oxygen conducts better than copper without oxygen is very much glossed over by the golden price bracket salesmen...
Wrinkle
Actually oxygen free copper (OFHC) conducts as well as oxygenated ETP copper. But to achieve that it needs to be of a higher intrinsic purity. Typically OFHC will be at least 99.9999% pure.
se
I've seen one example of this about 20 years ago. A contractor installed some smoke detectors in a laboratory building I worked at. He spliced solid wire to stranded wire extending existing strings of heads. The panel zone alarms he connected more heads to went into continuous nuissance alarm. There was a lot of RF from the labs in that building. The copper runs were the antennas and the junction between the solid and stranded copper were the detector diodes. I solved it by shunting the zone alarm inputs with .047 mfd caps. This was effectively a shunt at RF, open at DC which is what the alarms worked on. I've never seen anything like it though at audio frequencies.
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