"I discovered that each power cord sounded very different going into the Ayre L-5xe but totally the same going into the LTA. So I reached out to Mark Schneider at LTA to report what I found. He told me that David Berning, who designs the LTA gear, is a power supply specialist above all else and, because of the integrity and quality of the power supply in my LTA amplifier the sonic differences between power cord were negligible. In fact, the stock power cord from LTA sounded just as good as a $1500 cable I compared it to. So, I purchased one of the better performing (and more expensive) cords for my Ayre and another inexpensive cord for the LTA, saving myself several hundred dollars in the process."
Dodgealum,
Putting your money where it does the most good and not overspending where it doesn't is good advice.
|
"I have investigated cables for many years and power cable improvement seems differ with the component to which they are attached.
- components with "less-capable" power supplies tend to exhibit more of an improvement
- compared to the same cable when used on amps with massive power supplies, which tend to exhibit less of an improvement"
Williewonka,
That ihas been my experience as well. I have a Bryston Int. Amp that doesn't seem to care what PC I use to feed it with. Other Bryston Amp owners have voiced the same experience. Robustness in power supply design is an important factor.
|
".... I ask that all of you to please be respectful or I will "Hyphenate" you idiotic responses!"
bluemartini,
Does that mean that anyone who posts a differing opinion is an idiot?
|
bluemartini,
Thanks for the clarification. |
"@turnbowm - which Bryston do you have?
- I have the B135 integrated - great value and quality....
....And for components of the quality level of Bryston and LTA, one would need the very best power cables to achieve discernible improvements and that equates to $$$"
In answer to your question, I have the Bryston B60R which I have enjoyed for 19 years. I have tried various audiophile power cables in the past but the B60R doesn't seem to care one way or the other. Perhaps the robustness of the power supplies in Bryston amps explains their indifference.
|
mwoh419,
What about the Shunyata Venom PC doesn't the Oppo-105 like? |
vinylguy2016,
Being an engineer (EE) with 30+ years of experience in the industry, I understand where you're coming from. During listening tests of audio cables (speaker & interconnects), however, I found audible differences which can be explained by examination of material
(conductor & insulator)
properties and design differences (coaxial, twisted pair, etc.).
In the case of power cables, however, I have yet to find discernible differences between audiophile PCs and generic ones of equivalent gauge. IMHO, there is no benefit in using expensive, after-market PCs on equipment with properly designed power supplies. I believe that Bryston and Pass Labs are of the same opinion. |
"If you are able to relate the sonic differences to cable construction, I would assume you can relate that to measurable engineering quantities?"
atdavid,
Absolutely. I have found, for example, that low inductance is a desirable characteristic in speaker cables. On the other hand, low capacitance seems to be the key for interconnects.
Is there any scientific reasoning behind your choice of audio cables?
|
atdavid,
You never answered my question....
"Is there any scientific reasoning behind your choice of audio cables?"
|
GK,
You are correct. I was in the electronics industry, not audio. However, music and the equipment that provides it has been my passion for even longer. My engineering background comes into play when making any and all decisions related to audio. |
"I would be very surprised if anyone in the last 30 years ever said high capacitance or high inductance were virtues. So, I guess what I’m saying is what else is new? But surely we can agree there are other desirable cable and power cord characteristics. Please don’t tell me it all comes down to L, R, C. That horse has been beat to death."
GK,
I never said that "it all comes down to L,R and C." Material (conductor & insulator) properties and cable design are important factors, as previously mentioned. |
"Now about those values of capacitance and inductance where they become an issue?"
atdavid,
There are no specific values/limits for inductance and capacitance because of variables in the application. Your experience with amplifier instability using high capacitance speaker cables is a perfect example.
My preference for low inductance in speaker cables and low capacitance in interconnects is based on numerous listening sessions. There are other considerations, but these are my primary ones. |
twoleftears1,947 posts11-20-2019 10:36am"Any way you slice it, Noel Lee has a lot to answer for."
What exactly should Noel Lee answer for? |
"....if there are no specific values for inductance/capacitance, then how do you know you were comparing cables with higher/lower values? "
atdavid,
I always buy speaker cable in bulk and terminate them myself. I use mfg's published data and, if they don't provide it, I ask. Below are several examples that I've used....
Kimber 8TC: Ls = 0.09uH/m
Mogami W3104: Ls = 0.6uH/m |
atdavid, How is the series R-C network (Zobel) that is used to provide a constant impedance different from the series R-C circuit used by Polk to dampen power amp oscillations? To me, they serve a dual purpose. I thought you might find this excerpt from Nelson Pass's discussion of speaker cables to be of interest. ... "After a period of confusion, Matt Polk and I realized independently tahat the lack of a characteristic termination was causing the problem. Polk developed and patented a "damper" consisting of a .047uF capacitor and 6 ohm resistor in series placed across the loudspeaker, while I used the same network but with .1uF and 5 ohms. The results of this network are seen in Fig. 8 where the resonance in the pulsed waveform is damped out, restoring stability to an otherwise oscillating amplifier. Since Polk's commercial introduction of the damper circuit we have found it cures oscillation problems caused by the other exotic low inductance cables. It is necessary whenever a reasonably long length (>3 feet) of low inductance cable is mated with any wide bandwidth amplifier. It interacts unfavorably with twin lead conductors (Fig. 8) which require higher impedance values (say, .01uF, 60(2); however, twin lead's higher characteristic impedance and resonant frequencies are in any case unlikely to induce oscillation in amplifiers now available." https://www.passlabs.com/press/speaker-cables-science-or-snake-oil
|
atdavid432 posts11-20-2019 10:10am"Originally patented by Polk 30ish years ago."
Matt Polk did indeed patent the use of Zobel networks in loudspeakers. That was in response to power amps self-destructing when using Polk's high-capacitance Cobra speaker cables. The concept of Zobel networks, however, was developed by Otto Zobel of Bell Labs in 1923. |
"....The first failure he put down to simple component failure, but when the second amp fried very quickly after power on he suspected something else was the cause - I believed it to be his TOTL Cardas speaker cables which had a very high capacitance...."
Goertz ribbon speaker cables also have high-capacitance that can be problematic to the degree that they offer a 'R/C Link' to combat amplifier instability issues. The R/C Link (aka, Zobel Network) is a resistor in series with a capacitor that is placed across the amplifier output to keep the demons at bay.
|
atdavid438 posts11-20-2019 1:00pm"For the same reason an RC-snubber across a diode or FET is not a Zobel network ...."
They both have a resistor in series with a capacitor. To me, that makes them the same except for the name. I guess we'll have to agree to disagree. |
"....What it does not address is differential voltages between equipment locally, usually most influenced by grounds, though ground line interaction is possible. Do you need $20K of power cords to solve this? No, $100 of copper strapping between equipment grounds will do far more. There is the potential for power cord to interconnect EMI, but again you don't need a super expensive cord to fix..."
atdavid,
Good point. Circuit designers work hard to achieve a common (Star) ground point in their equipment designs and then we undo their best efforts by plugging the pieces of equipment into various outlets and power conditioners in the room without regard for establishing a common system ground. The Star grounding concept should be used at the system level and copper strapping is one way to achieve that.
|
mikepowellaudio,
Making a power cable that is able to degrade sound does not prove that an audiophile-grade power cable will improve sound compared to a generic one of equal gauge. The only thing you proved is that you know how to make a bad power cable. |
