Saturday 22 February 2020

MEASUREMENTS: Archimago's Colorful Speaker Cables, KnuKonceptz, AmazonBasics, and "freebie" speaker cable. (And changes at Audiophile Style.)

As hinted at with the article a couple weeks back of my simple DIY speaker cables, let's spend some time considering the basic speaker cable measurements, how these affect the hi-fi system, and get a sense of the magnitude of effects to be aware of.

If you read the audiophile publications, it's not uncommon to see articles paying lip service to the importance of science in cables and measurements, yet at its core, they're often written to perpetuate fears, uncertainties, and doubts (FUD). IMO, this recent Positive Feedback article is a good example in that it acknowledges resistance, inductance, and capacitance but goes out of its way to describe complexities without actually giving you any contextual information about the values of these quantities. Notice the title. The "snake oilish" nature of something isn't nullified just because acknowledgement of the term is used. And certainly, denial is to be expected from supporters of "snake oil".

Saturday 15 February 2020

MEASUREMENTS & LISTENING: Topping D30 DAC by Greg Dunn. (And briefly, more USB cable nonsense.)

[Ed: Every once awhile, it's a pleasure to have guest posters adding their voice to this blog! There are many folks out there doing measurements, experiments, and I've certainly been in contact with a number of audiophiles with great stories about the gear they have, music they love, and the audiophile pursuit in general!

A few weeks back, Greg got in touch with me around the Topping D30 DAC that he has. This DAC was brought up in comment discussions back in 2018. The D30 measured quite well on Audio Science Review, but has been blasted as subjectively sounding bad - "like ass" as it were - on the Super Best Audio Friends forum. Elsewhere in that SBAF comment thread, the D30 was described as having "poor soundstage and poor timbre".

With this polarization of opinion, it's great to see Greg stepping up with his own opinion based on objective testing and subjective listening... Take it away, Greg!]

Saturday 8 February 2020

DIY: Archimago's Colorful Set of Speaker Cables. (And about that Darko/McGowan "EXPERT" interview on USB cables & other claims.)

While it's probably perilous to guess which cables "make the most difference" (just look at the different opinions here), arguably, other than very-low-voltage phono cables that can pick up interference easily, I'm guessing that speaker cables probably can make the most difference in a sound system on account of longer lengths and the fact that speakers are low impedance devices. As a result, the additional resistance, inductance, and capacitance of speaker cables may be relevant to performance.

Furthermore, in extreme cases one could run into systemic instabilities, for example years ago the Polk Cobra cable was called an "amp killer" on account of high capacitance and very low inductance. This Nelson Pass article from back in 1980 listed that cable as having 500pF/ft capacitance and discussed the need for a damping network to avoid high-frequency oscillation with high bandwidth amplifiers. Clearly sometimes the amplifier might "see" the difference a cable introduces even if anomalies are inaudible.

Saturday 1 February 2020

MEASUREMENTS: Do power cables make a difference with audio amplifiers?

Alright guys, as you probably know, here at the Musings, I'm not in general a "cable believer". This doesn't mean I'm a "cable denier", after all, I need them in order to hear something from the system :-). Over the years I have written about silly cable claims, and here's the summary post looking at all the cable varieties I've measured (I will of course include this article in there as well).

With measurements dating back to 2013, I have neither heard nor seen any evidence to compel me to recant my opinions on this matter. Furthermore, I have not seen any new articles exploring the topic with any kind of depth in the audiophile press. No audio cable company has produced material demonstrating a believable, sonic benefits for their $$$$ products. Despite countless ads in magazines, I see a lack of accountability from the mainstream press to investigate; it's really just about maintaining the status quo and promoting sales of high-margin luxury products as far as I can tell. No magazine wants to purposely publish stuff that results in loss of advertising revenue from a whole segment of products, right?

Up to now, the power cable measurements I've published have been with low-power devices (ie. measuring DAC output quality with different power cables), but what happens with higher current demands, when the device needs >100W from the wall socket? In the last few months, since I've been working on amplifier measurements, I have had the opportunity to try measuring power amplifier output using different power cables.