MUSINGS: On art, artist appreciation, and "core music"... by 24bitbob

I received a wonderful E-mail from reader 24bitbob in Australia just before the clock turned 2020; considering how the world has changed this year, it feels like the message came ages ago!

As I've mentioned over the years, it is wonderful chatting to audiophiles from all around the world. It's great to hear and consider the insights of others. Ultimately appreciate what the audiophile hobby has meant to them (you!) as a source of joy and love of the music...

Mon 12/30/2019 4:56 AM

Hi Arch,

I’ve followed your blog for a while and made a few comments / observations along the way under the pseudonym ‘24bitbob’. Truth be told I’ve enjoyed hi-fi as a hobby since 1970-something, and I’ve learned at various times the trap of getting caught having to upgrade things. If taken too far it leads to frustration more than happiness, so I dabble in the hobby; in and out, in and out.

MUSINGS: COVID-19 - "WE CANNOT LET THE CURE BE WORSE THAN THE PROBLEM..."

Thought I'd put up a post today as a bit of a "comment cleaner" for ongoing discussions. A few days have passed, I'm not seeing much change here in Canada. Yeah, more testing done, more positive cases, but so far so good in terms of emergency departments not being overwhelmed. Preparations looking OK and containment systems not being breached. Strong health policy seems to be working within the hospital system that I can see.

MUSINGS: COVID-19 - "Abundance of Caution" | "Abundance of Fear"

As discussed a few days ago, there is remarkable fear out there with COVID-19. Last night, as I was checking out the news, I clicked on Drudge Report to see what's going on in this world and got that screen above.

Wow. What a time we live in. I suspect if we checked Drudge on September 11, 2001, the top part of the screen with numerous headlines would have all been about the same topic as well!

COVID-19: A few thoughts... Finding tranquility in a time of panic.

Greetings,

For the most part, I talk about rather petty stuff like sound equipment and audiophile discussions on this blog. :-) However, nothing has stopped me from posting on other topics of interest over the years! I was supposed to be on Spring Break this week but with all the flight shutdowns, I'm staying put in Vancouver which gives me time to watch the news, check in on work once awhile, and think about the state of the world.

Needless to say, things have changed markedly within weeks due to the SARS-CoV-2 virus and the COVID-19 disease pandemic that it causes. I thought I'd put up a post this week to document a few facts and figures I've come across, many of which not seemingly focused on as much in the media. As usual, I'm interested in the big picture and let's try to see the context of what's going on.

As per audiophile discussions here, let's remain science-driven and not get off track into tinfoil-hat, homeopathic, conspiratorial, la-la-land, OK?

MUSINGS: "Which measurements matter?" Importance of considering the complete audio chain. And a listen to room DSP filters...

Very busy these last few days so I thought let's address an interesting discussion question I've seen over the last while about measurements and audibility. Here's a forum comment from tapatrick over on Audiophile Style the other day:

I think you have done a good job in your blog post of covering all the relevant areas involved from music production to listening. And maybe the conversation is now concluded. If only everyone would acknowledge and respect each others 'intent' as you put it then there would be a lot less misunderstanding. I am none the wiser which measurements matter but I have to say I'm now clear that measuring and analysing equipment outside of listening leaves me cold. I will leave that to others more qualified but I will keep an eye on developments.. .

MUSINGS: Audio & Music - The audiophile Big Picture view... (And "objectivists are no fun".)

It has been a very busy week at work and obviously the world this week has been going through all kinds of turmoil on account of Coronavirus and the very real effects it's having on travel, production, the economy, and of course health care!

Over the last week, I spent some time on Audiophile Style chatting with the folks there in the thread on "Why are objective assessments important...". As you can see, many topics were covered including subjectivity, objectivity, what is a "perfect" reproduction chain, whether objective results correlate with subjective experience, all the way to a discussion of neuroscience, the mind, etc...

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".

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!]

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.

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.

INTERNET BLIND TEST: Is high Harmonic Distortion in music audible? (plus Pet Shop Boys' newest, HRA needs HDR)

Another year, another Internet Blind Test, my friends! For me, doing this is important because it keeps us honest. It's worth reading this article in Audioholics published recently for an overview of the complexity of perception. I believe it's essential that audiophiles have an opportunity to participate in exercises of perception which I hope can enlighten ourselves and in aggregate, enlighten each other.

It's good to capture naturalistic data of audiophiles "in the wild" on top of information we may read from the "ivory tower" of Academia and profit-motive driven claims from Industry. Arguably, this is some of the most useful data. We can for example quite easily measure amazing levels of performance these days from our devices, but if we never correlate this to audibility, the data says nothing about relevance to humans, which at the end of the day is the only intent of these devices!

If you remember, last year we did the "Do digital audio players sound different?" test (the results systematically discussed starting here). This time around, in late 2019, Paul K [aka pkane] (who also wrote DeltaWave) contacted me to try out the early builds of his new software called "Distort"; aptly named software that allows us to purposely introduce anomalies into audio data. Among a number of distortions one could introduce is the one we've all heard off - harmonic distortion.

MEASUREMENTS: Hypex nCore NC252MP Amplifier (+ Subjective opinions around objective testing, and CES2020)

Alright, you knew this was coming from the post last week with assembly details for this amp.

As discussed, this is an easily assembled single-board OEM Class D stereo amplifier rated at 150Wrms into 8Ω, 250W into 4Ω, and 180W into 2Ω. The enclosure comes from Ghent Audio. The amplifier is based on the Hypex nCore "phase shift controlled self-oscillating loop" design.

Let's run this box through my usual MOAR testbench as previously described and see what kind of data we get. In general for these tests, the signal path for measurements looks like this:

RME ADI-2 Pro FS AKM DAC (signal generator) --> XLR --> Douk/Nobsound NS-05P passive attenuator --> XLR --> Hypex NC252MP amplifier --> Test leads --> BNC unbalanced input of Linear Audio Autoranger MK II --> Balanced TRS/XLR --> RME ADI-2 Pro ADC --> USB --> Surface Pro 3 laptop

I'll also have some oscilloscope measurements where the test leads will be directed towards the oscilloscope instead of Autoranger and RME ADI-2 Pro.