Mr. Caelin Gabriel obviously has extensive knowledge about this subject. I believe, however, he is also good at mixing facts with fiction.
Lets analyze some of his quotes.
Mr.Caelin Gabriel: "ALL of the wire and connectors can and do affect the performance of the component's power supply."
Me: wires are in series with the components power supply (induction + resistance). And also sort of in parallel (capacitance) so yes, wire could affect the performance of the connected power supply in a very small amount.
A higher resistance will reduce peak powers drawn which is important as shown below here. A higher inductance will reduce the 'energy' of HF garbage.
One has to realize that last meter is in series with tens to hundreds of meters of 'crappy cable' with tens to hundreds times the inductance and resistance and within that length lots of other devices also 'distort' that voltage.
A very complex system of 'noise generators' and (short peak) currents drawn that are 'flattening' the peaks of the AC mains voltage.
Yeah ... the last meter will make the difference ... sure it will.
Unless one is using a regenerative UPS of course, one on each device. Where each one of those devices emits their own HF garbage and usually has lots of filters in there... that are bad ... and usually have trouble providing high peak currents. Ohh the waspnest this is.
All true... but I have yet to see measurements that clearly show a real world situation where the DC output of a power supply is really 'better' (cleaner or has less ripple referenced to the circuit ground/common) when 2 different (decent quality) mains cables are used.
Any audio device works on DC so when there is no significant variance in the DC.
Why not show pictures with 'proof' (that aren't doctored in some way, which is so easy to do.. the doctoring part) ?
Mr.Caelin Gabriel: "There are two aspects to power transmission: the electromagnetic wave and the current flow. The current itself cannot be contaminated but the electromagnetic wave can be modulated with other frequencies. We usually call these other frequencies noise or Electromagnetic Interference (EMI). Within the various parts of a power circuit there may be EMI in certain parts that is not present in others. Electromagnetic energy can be transformed or redirected to lessen their effects.
me: True. What's it have to do with the DC output from a powersupply ? In the sense that 1 meter of cable, that does not appear to have any different inductance, resistance or capacitance, can change the DC output so dramatically that it can actually change the waveform of an audiocircuit fed with that DC.
Mr.Caelin Gabriel: "Some power cords use capacitors, inductors, or ferrites in an attempt to control the electromagnetic fields around the audio component. The success of such an approach is completely dependent upon the specific design and the reactance of the power supply of the component to which the power cable is attached."
me: True.
This means that some 'filtered' cords improve AC 'quality' (but not necesarily the resulting DC) while the same cord can make some AC components (i.e. RF garbage) worse.
So will almost all AC filters in any device. As a lot of devices using SMPS (Switched mode Power Supplies) have an AC filter to comply to minimum requirements.
Why would one buy such a cable... Shunyata cables don't appear to have a filter in it nor do 99.99% of all power cables so why mention these cables?
Mr.Caelin Gabriel: "The power cord is not the last 6 feet, it is the first 6 feet from the perspective of the component. As stated in #1 the local current and electromagnetic effects directly affect the sonic performance of the component."
me: For emitted signals the power cord is the first 6 feet. For the received power (what a device works on) it is the last 6 feet in series with the hundreds of feet before it.
Mr.Caelin Gabriel stated in #1 response: "
ALL of the wire and connectors can and do affect the performance of the component's power supply." he certainly did not say: "
the sonic performance of the component" but said "
power supply" which are 2 very different things.
One is a fact "power supply" the other an opinion "sonic performance".
Mr.Caelin Gabriel: "A primary source of audible sonic degradation is caused by the power supplies in our audio/video components. Most components use FWBR (full wave bridge rectifier) power supplies that generate an incredible amount of transient noise when the rectifiers switch off. The design of a power cable can significantly affect the reactance of these signals within the power supply. The power cable is effectively part of the primary winding of the power transformer. "
me: Well any rectifier (FWBR or SWR) will indeed generate very small amounts of RF peaks. How 'bad' this RF type of signals is depends on whether the power supply has sufficient '
snubbering' (I love that word) and if there is a filter used or not.
Those switching artifacts are only present on the input side of the rectifier and not on the DC side. A poor design can indeed 'conduct' some of these (very small amplitude) RF signals in so called 'common mode' in the DC circuit.
Nothing any cable can improve performance on.
Common mode signals may be a problem when connected to other devices not by themselves as all DC power lines and 'common' are all modulated in the same way effectively having no influence between the DC rails at all so are not 'modulating' the actual music signal.
Mr.Caelin Gabriel: "Most power supply filters are ineffective at blocking very high frequency noise components and much of it is passed through to the DC rails. The sonic effects of this include: high background noise levels, blurred or slurred transients and a general lack of clarity and purity of the sound or visual image."
me: yes, most power supply filters are ineffective at GHz noise components.
The 'sonic effects' part is totally made up. No proof has ever been presented that transients in music signals are affected nor that clarity (in the 3-5kHz range) is affected nor that 'purity' is affected.
Mr.Caelin Gabriel: "As long as power supply design is based upon FWBRs or switching supplies, the power cord will always be significant.”
me: Indeed without a power cord the device will not be powered and do nothing. In that sense it is true. Very significant.
Mr.Caelin Gabriel: "A power cable on the other hand is not transmitting a signal. It is conducting A.C. power and its sonic superiority will be determined by its ability to deliver current (steady-state and instantaneous) and its ability to deal with the EMI effects of the components to which it is attached."
me: Well an AC power cord is feeding the mains voltage to the device. Through it there are short (and high peak current) very short 'pulses' with lots of harmonics that are only present at the peaks of a sinewave. The rest of the time nothing happens in there. There is no 'audio' drawn through the cables at all.
Just short peaks.
Below the harmonics (current, not voltage) that are 'injected' into the mains using a FWBR.
Below a scopeshot I made of the currents running in the diode (so on the secondary side, the current in the mains side of course is much lower depending on the winding ratio, it is part of
this article
Mr.Caelin Gabriel: "Silver, copper, brass, gold and others all "sound" different."
me: no they just have a different amount of resistance when diameter is the same, and a very strong effect on ones expectation bias by association.
I have yet to see any cable material acting as a bandwidth filter in and well outside of the audible band or add audible amounts of distortion.
I have seen poor connectors do that though, cable materials .. no and that is with audio cables. So.. an audiophile assumption.
How would any of these materials change the pulses present in a power cable and have an audible effect when no audio is passing through these materials ?
Would like to see some technical evidence. I haven't been able to find any.
Mr.Caelin Gabriel: ""Many components use a power inlet IEC that has an integrated "L" or "pi" filter. The quality of these devices varies dramatically."
me: Yes, very true. What does it have to do with audio quality ? It just is a loose remark.
Mr.Caelin Gabriel: "Many of these IEC packages were created for office and computer products and are required to pass certification tests for EMI emissions."
me: Yes, very true. What does it have to do with audio quality ?
Mr.Caelin Gabriel: "Shielding can be a two-edged sword. On one hand, it can reduce radiated fields from impacting other components. On the other hand, the shielding may induce re-radiated fields onto the cable or component that it is being used in. Sometimes the cure may be worse than the illness."
me: Yes, very true. What does it have to do with audio quality unless the power cords run parallel with (poorly or not shielded) audio cables.
Mr.Caelin Gabriel: "There is no silver bullet and there is no rote formula that works in all cases."
me: Hmm ... I thought Shunyata cables did ?