AudioQuest DragonFly Copper: Review and Measurements. A classic dongle DAC returns. (And Rubber Soul - 2026 remix.)

Audiophiles following the news cycle know by now that after seven years, AudioQuest has released a new DragonFly USB DAC. The DragonFly Copper (US$250, CAD$345) was spoken of at High End Vienna 2026 and started shipping in September, replacing the Cobalt at the flagship. As usual with a new Dragonfly, the forums and review sites lit up within days of the announcement (see sites like this, or this). Recently, I even got E-mails from blog readers asking when I was going to review this device, so here it is by request. 😉

Over the years, I've measured these little USB DACs going back to the DragonFly v1.2 in 2014. More recently, I wrote the two-part series on the DragonFly Black in 2017 with a good chunk of that examining MQA "rendering", and then the three-way comparison of the Cobalt, Red, and v1.2 in 2019. In that last article, the Cobalt did not exactly manage glorious performance on the test bench, clipping at 100% volume with 0dBFS material, THD merely on par with the ancient v1.2, and higher idle current draw than the Red despite all the "low power" marketing. The Red, as I wrote back then, was the winner for lowest distortion among the Dragonflies.

So in my mind, the Copper arrives with something to prove at least to this "more objective" audiophile if it truly is to be a better device. In the company literature, AudioQuest claims to have made progress in 3 main areas: "twice the output power" as a headphone amp, "25% lower current draw", and the "high-conductivity copper-plated case" allows "for improved RF-noise drainage". We'll have a look.

I bought this DAC through consumer channels and this post is in no way company-sponsored.

AuraEngine: Perfectionist off-line mega-tap digital filtering - with hybrid-phase transient detection & blending.

As you know, while digital oversampling filters have been around for ages (4x oversampling available back in the '80s), audiophiles probably got more interested in digital filters thanks to Bob Stuart, and Meridian by 2009 talking about "apodizing" filters. DACs started allowing different filter options. And spin-offs like MQA took things too far utilizing poor designs through the 2010's (and still looking for a reason to exist).

Years ago now, I spent quite a bit of time talking about digital filters across articles like this and contemplating things like pre-ringing here. There were also discussions of using the intermediate phase setting as a compromise. And we even ran a blind test to compare strong pre-ringing vs. no-pre-ringing minimum phase settings.

While I think I've exhausted my time exploring such things at the base level, ever-more-precise filtering options have been available for audiophiles to use. HQPlayer has many realtime software-based playback settings including DSD transcoding. Companies like Chord/Rob Watts have taken their stand on using ultra-tap-length linear phase filters (to the point of extreme IMO).

Off-line upsampling of high precision can also be achieved using software like Pan Galactic Gargle Blaster (PGGB) in 2021 -  I see they have a PGGB+ version now with DSD and up to "ludicrous" 256-bit processing.

Well friends, it's 2026 and the other day I was contacted by Toxa Dev about his new ultra-accurate upsampling system called AuraEngine (current version 1.2.2) available on Github; full source code published and freely released for non-commercial use. You can also download and run the pre-built Windows portable app here. Notice that there are three downloads available: Starter 1M-taps, Standard 10M-taps, and Reference 30M-taps. Pick your level of obsession err... weapon against weak upsampling!

Inexpensive USB2.0 Digital-to-Digital Converters (DDC) Pt.1: Douk Audio U2 PRO (Upgrade Version) and SMSL PO100 PRO - initial look, about I²S-HDMI. In praise of unofficial Atmos mixes!

This SMSL unit also does MQA decoding for those who want the feature. Unlike the Douk, this box only has an LED to indicate MQA decoding status but does not tell us the PCM or DSD samplerate.

While I've tested some inexpensive devices (like the Topping D10s DAC) which have the ability to convert USB 2.0 input into S/PDIF output, I have not specifically looked into these Digital-to-Digital Converter boxes which some audiophile reviewers (like this fellow, and this) seem to rave about.

For me, there just hasn't been any reason to be particularly interested since other than conversion from one interface type to another, the other promise of such devices - the reclocking capability - just hasn't been of great interest to me. As far as I can tell from listening, it's not like jitter has ever really been much of an issue unless severely bad for any decent modern device I've ever come across even at low price points (nor was jitter really an issue even with old CD players)!

However, since I have not tested I²S/I2S/IIS, I figure I'd buy both the Douk Audio U2 PRO 2025 upgrade version (US$63; Amazon Canada) and SMSL PO100 PRO (US$74; Amazon Canada) boxes to try out; have a listen and run some measurements. Unfortunately due to time limits, I'm not quite ready to show the measurements yet, so keep an eye out for those results, perhaps next week! For now let's just introduce you to these devices and talk about the I²S-HDMI connection.

As typical of the majority of my reviews/critiques, I bought these through retail channels.

More Audio Potpourri: What's the best sample rate converter? The other father of MP3 (James D. Johnston "JJ"). Are measurements important? And TAS' "objective" confusion.

For this post, let's discuss a few other audiophile items that have come my way in recent weeks.

First, let's talk about something I haven't brought up for awhile now: sample rate conversion (SRC).

A few weeks ago, Spoon (a.k.a. Steven Elkins of Illustrate) sent me an E-mail about his new src.hydrogenaudio.org page evaluating and ranking the qualities of various software sample rate converters. I believe the page has been online since late 2025. Check out the forum discussion about the project as well.

Audiophile Potpourri: December 2025 web traffic among audio sites, price of cables poll, and flashback 2014 while looking ahead.

Let's have some fun this week on miscellaneous topics.

Occasionally, I'll highlight items I've either written or found on audio discussion forums I think would be good to share. One reason I decided to start doing a blog beyond just contributing to forum discussions was precisely because while the public forums are great for interactions with community members, meaningful posts often become obscured behind pages and pages of chit chat, irrelevant responses, and sometimes unpleasant arguments.

[I've unfortunately witnessed situations where very meaningful threads are closed off prematurely based on the bias of moderators. Even worse, threads with useful discussions might be erased entirely from existence which I feel is an slap in the face of well-meaning participants who put their time and efforts into thoughtful reflections. This is nothing new in the audiophile world; for example last year Stereophile scrubbed their website of all public comments accumulated over decades!

While I acknowledge the right of a website's owner to do such things, that doesn't make it any more palatable. I certainly understand the need for moderation in removing nonsensical, trollish, unethical, or crude statements that add nothing to promote thoughtful discussions.]

Speaking of forums and websites, I thought here in early 2026 it would be fun to explore website traffic numbers of some of the most common audiophile/audio sites using a common metric. One can get monthly visit numbers from Similarweb for free, a well-known website traffic tracker.

MUSINGS: On various characters in the audiophile hobby, debates, opinions and the Hearing Test.

Hey everyone, once awhile I'll take a look at stuff YouTube offers me in the feed that might be interesting. I see that in the last few months, there has been this channel called "The HiFi Five" and in Episode 6 (November 19, 2025) they invited Dennis Burger of SoundStage! for a discussion. I found this video actually quite interesting as an illustration of objective/subjective mindsets, biases, and the personality styles that come through in communicating such ideas.

Check this out if you have time for a deeper dive with discussion to follow, related to the contents and characters:

Auro-3D "Auro-Matic": Preset and Strength settings and effects. (Brief look at Dolby Surround Upmixer and DTS Neural:X.)

A number of months back, I talked about the nVidia Shield TV Pro box and explored Auro-3D which is another technology for reproduction of immersive sound with height layers. As noted in that post, I've seen comments over time about the use of Auro-3D's "Auro-Matic" surround upmixing algorithm for music playback as being the preferred setting compared to Dolby Surround Upmixer [DSU], and DTS Neural:X being the other two common options in modern AV receivers. As a reminder, while Auro-3D could use object-oriented tools in production, it is delivered as channel-based playback rather than the hybrid channel/object systems like Dolby Atmos and DTS:X.

Having now owned my Integra DRX-8.4 for about a year and listening for myself, I concur that for 2.0 and 5.1 upmixing, I tend to prefer using Auro-Matic to expand the 3D image into the height and surround channels. For most music material, Auro's method is noticeably "fuller" in presentation without sounding harsh. It also has more options as we can see in the settings menu for Onkyo and Integra receivers that have this feature:

SUMMER MUSINGS: What could possibly be wrong with the High-End Audiophile Industry?! 🤔 (The supplier side of audiophoolery.)

Alas all good things end including summer, so this will be the last instalment to my "Summer Musings" series for the year. For completeness, since we talked about the "audiophool" consumer hobbyist last time, let's make sure to address the other side of the coin when it comes to audiophile silliness - the supplier - manufacturers, and the media that sell us stuff.

As a pre-emptive comment against sounding like a grumpy old man who doesn't want audiophiles to have fun, let me just say that this commentary is not against "having fun". If fun means enjoying your music, trying out different hardware, exploring the various sounds you can achieve at all kinds of price points, I'm totally on board with that!

However, freedom to do all kinds of things obviously doesn't imply that we shut down our brains and accept that "anything goes!". Many things can be a lot of fun at the time but not good for us, the hangover could be nasty, and regrets more common than we might want to admit. So if there's foolishness when it comes to the Industry itself, let's make sure to think about that and come to terms with it for ourselves.

In the recent post about audiophoolery, Solderdude and Mikhail wrote the following comments:

Solderdude 18 August 2025 at 23:13

I have often wondered how many snake-oil sellers actually believe in what they are selling and are equally 'misguided' by their hearing (they are human after all). Examples could be Paul McClown and Danny.

Some, for sure, are just unscrupulous money grabbers (think Machina Dynamica and absurdly priced cable sellers).

And, oh boy, most audiophools as well as audiophiles usually have plenty of money to spend on their hobby and being human and lacking actual knowledge are very easy to 'hear' things that aren't there just as they are equally fooled by optical illusions.

Some might simply have fallen for the same 'perception effects' and fully believe in what they are selling. Are these sellers also unscrupulous ?

Perhaps only the ones that sell their wares at way too high margins for what it costs to manufacture ?

Mikhail 19 August 2025 at 07:18

Should we start calling this sector of the audio industry "alternative engineering"? If there was Federal Audio Administration they would require putting labels like "Claims not verified by double blind testing" and "This product is not intended to actually improve the sound of your audio system" on their products.

Interesting points. Let's talk about this.

SUMMER MUSINGS: Paired speaker testing, more crossover thoughts, running tests ourselves and for ALL speaker reviews!

Paradigm Signature S8 v.3 speakers with grilles off. miniDSP UMIK-1 microphone for some simple testing with Room EQ Wizard (REW).

Well it's summertime which means (hopefully) a bit more opportunity to enjoy the nice weather around here in Vancouver with the family, more time to listen to music, maybe a little trip out of town on weekends.

As for my audiophile interests, it also gives me time to think about the broad topics and maybe run a little bit of testing here and there. Often these summer articles flesh out ideas and results covered over the last few months I may have left aside or on the "cutting floor" when writing.

This post will be along those lines in that these results were actually captured back in the January-February 2025 timeframe when I was doing the ferrofluid replacement for my tweeters, and then subsequent discussions about "audiophile" crossover parts and addressing beliefs of people like GR-Research/Danny Richie.

Since I grabbed these measurements and pictures when I was considering the importance (or not) of crossover part affecting sound quality, I thought I'd post them with some further summertime-meandering and related discussions.

Part II: Topping DX9 "15th Anniversary" Limited Edition DAC & Headphone Amplifier - PCM Filters, Frequency Response & DAC Resolution. (And Trump's ongoing oblivious narcissistic tariff buffoonery.) [Firmware 1.23 Update]

Continuing with the discussion in Part I, let's proceed with Part II of our look at the Topping DX9 "15th Anniversary" DAC as we wade into some of the technical capabilities and performance of this device.

As I discussed the other week, my belief is that for relatively "simple" devices like DACs where what we want is as-accurate-as-possible conversion of the audio data into the analog voltages, measurements are really all we need to characterize the accuracy, the transparency of the device using modern tests and instruments that are capable of capturing details beyond the ability of human hearing. The capability for any device to achieve transparency of course does not guarantee that we'll be able to enjoy the sound or the music which are determined by individual subjective psychological factors.

With that, let's jump into some PCM measurements of this Topping flagship product.

nVidia Shield TV Pro (2019 version), still relevant in 2025! A listen to Auro-3D & Auro-Matic Upsampler.

Hey guys, I thought it would be fun to talk about something that's been around quite awhile already but which I still bought in 2025. As per the image above, it's the nVidia Shield TV Pro (US$200, CAD$260). For years, I've been using the Apple TV 4K (2nd Gen, 2021) which is a fine unit with all the bells and UI whistles of the Apple ecosystem. But it is missing something that "serious" movie audio lovers - and even audiophile music lovers - might want; lossless audio bit-streaming for Dolby TrueHD/Atmos and DTS/HDMA/X.

That's right, sadly, after all these years, Apple doesn't care to update the AppleTV to support basic bit-streamed audio. 😢

Note that I don't necessarily blame them as a company, they make no money off local libraries of UHD/BluRay-ripped content. So if I were running the business, I'd also think twice about getting developers to support a feature that at this time in history they will make no streaming subscription revenue from. Streaming services - Apple TV, Apple Music, Netflix, Prime Video - all do not send lossless multichannel audio content, opting typically for lossy Dolby EAC3 with or without Atmos. Not supporting much beyond the basic feature set is nothing new with Apple as part of their KISS closed ecosystem mentality. (The only lossless multichannel I've come across are the few albums on Qobuz.)

Since 2021, without lossless bit-streaming to the receiver, I've been using Infuse PRO on the Apple TV which will decode Dolby TrueHD and DTS-HD Master Audio to multichannel PCM. Doing this removes the embedded Atmos or DTS:X height effects (can turn on Dolby Surround Upmixer or DTS Neural X to extract some content back). At least lossy EAC3-Atmos is sent directly to the receiver.

Therefore in 2025, the only other mainstream choice is still the Shield TV, a device that seems to be catered more to the home-theater enthusiast with lossless audio - thanks nVidia.

Do CD and lossless streaming sound the same? A response to ana[dia]log video. And on excessive complications in the audiophile culture.

Today's blog post was inspired by Mister MB in a comment he made on the post last week (about GR-Research, and the hype around passive crossover components):

Hey Arch,

Slightly unrelated, but I thought you'd be interested in this recent video about CDs vs Streaming by Guido of Anadialog:

https://www.youtube.com/watch?v=pY8PeMpT2DE

What do you think? ...

Thanks for the link MB. I've come across the ANA[DIA]LOG YouTube channel but admittedly haven't spent much time watching the contents. I certainly appreciate the host, Guido's, passion and energy! I see the content caters more to physical music media, especially tapes and LPs. As you probably know, for me, subjective preferences aside, analog media represent lower-resolution sound; no offence to vinyl/tape lovers, it's just a statement of fact (especially with LP/vinyl) given the much higher resolution capabilities of modern digital ADC and DACs, achieved with less hassle.

Good to hear about the interest around CDs these days. I guess what's old eventually becomes new (maybe even trendy) again at some point after a couple of generations! Although I have a feeling Edison's wax cylinders might have a tougher time staging a comeback. 🙂

Lenbrook's MQA: The Next Generation - QRONO, FOQUS, and other AQWARD things. And listening impressions from the non-audiophile press.

Happy new year, audiophiles!

Other than a quick comment here and there in 2024, I'm glad that I didn't spend much time on MQA-focused material. The last we talked at length about MQA was over a year ago in December 2023 with the final sale of MQA to Lenbrook at the bargain basement sale price. My, how time flies! As much as I would love to never think/write about MQA again, this thing won't disappear. 🧟

So I figured at the start of 2025, since there could be some MQA-related stuff later this year with possible new product announcements and such, let's anticipate a bit and consider the developments in this continuing saga.

The name "MQA" persists as part of Lenbrook's "MQA Labs" as the name MQA Ltd. has been re-registered to a food sales agent in the UK. Through 2024, we've been seeing the word "QRONO" hitting the news a few times already. In late 2024, there have been more articles in the audiophile press such as this in The Absolute Sound, and What Hi-Fi?. So, let's talk about what this seems to be about and what they're trying to do.

MUSINGS: Words, worldviews, and the multimodal expansion of AI. [Let's have some fun with generative AI in 2024.]

"If language is as inextricably tied up with consciousness as it seems to be, then the continuing diminishment of our inclination to use it to express in letters the times in which we live could mean that an element of human consciousness itself is on the verge of disappearing."   --- Anonymous

I saw this interesting comment above during my readings across the Internet this past week. I guess it triggered in me some thoughts around writing articles these days with the rise of audience engagement with video, the bold new world of AI "generative" technologies, and trust in the sources we read/listen/watch. In this post, let's just "shoot the breeze" with some meandering musings around these themes and navigate through some complex ideas... 🤓

Years ago, during the heat of the MQA Affair, I talked about writing these blog pages using a pseudonym. That was in response to MQA's issue around anonymity; perhaps they were paranoid that I was an industry player or working for a competitor. These days, in the face of increasingly sophisticated artificial agents roaming the Internet, foreign influences, machine-generated content (including artificially generated audio and video), I think it's quickly becoming old-fashioned to worry about just mere human anonymity having nefarious intent!

Now that my writings have spanned more than a decade, I trust that readers know that I'm actually very much a "real" guy behind the keyboard who's passionate about audio reproduction, sharing my perspectives on the high-fidelity pursuit as an audiophile of the early 21st Century. I have my philosophical views, thoughts on the importance of objective hardware fidelity and adequacy, the importance music itself as the origin of the art we admire and the emotions evoked rather than attributing too much of this to the hardware.

Furthermore, I trust my writings have been internally consistent in presenting my audiophile worldview, built up based on objective fundamentals. Comparatively, I think this is quite different from what we typically read elsewhere coming from most magazine writers. My beliefs are often at odds with the interviews given by Industry experts, and I hope these accumulated articles have been vastly more in-depth than superficial opinions on social media.

The Dolby Atmos Music Target Curve. And on being an audiophile "tonmeister".

[For the post this week, let's take a pause from the Pacific Audio Fest 2024 discussions (last 2 weeks). Next week we'll have a Part III discussion about audio shows.]

Standardization is generally good.

I've discussed in previous posts that Dolby Atmos defines loudness characteristics for recordings and this has helped preserve dynamic range in multichannel/Atmos albums following their guidelines. Likewise, we can benefit from standardization of the frequency response as this will allow us to better "translate" the sound from the studio into our sound rooms. This idea is not new for audiophiles. The ill-fated (with good reason) MQA promised that we could experience the "sound of the studio", but they never could deliver in a large part because there was never any standardization for essential parameters like the frequency response, among other failings. In the same way, back in the day (~2014), this was the promise of hi-res audio by Neil Young and Pono that you would somehow get the "finest digital copy" and this would represent the sound the artists intended from the studio; clearly they overpromised and under-delivered by 2015.

It's one thing to standardize between the studio and home ("inter-system") playback, but it's also important to standardize "intra-system" - that is, between all the speakers in your set-up when you're doing multichannel such that each speaker is calibrated to the same timbre. This is important in a multichannel layout since we do not want "objects" moving through space changing tonality because of mismatch between speakers around the listener. The Dolby Atmos Music Target Curve is Dolby's recommendation for the music studio frequency response. This curve evolved from the X-Curve, an 'X'perimental frequency response based on some early empirical work exploring the performance of actual theater sound systems starting in the 1970's, and evolved over the years. See this paper for more details, note some similarity of the Dolby Atmos Music Target Curve to the SMPTE 202M - 1998 X-Curve.

As with all things in audio, nothing wrong with asking whether this curve is the "best". 🤔

Pacific Audio Fest 2024: Part I. [And expensive speaker cables unanimously turned down in a blind test?! 😕]

This is the third year for the Pacific Audio Fest which first started in 2022, basically after the COVID-19 pandemic reopenings. I think the first 2 years of the show were quite similar in size but this third show is clearly a smaller event with fewer display rooms and less stalls in the Marketplace. Correlated with that, I also noticed fewer headphone set-ups to try out.

To be honest, while I think this probably was disappointing for some, I only had a couple of days to visit anyways so this actually worked out driving into Seattle on Saturday morning, stayed a night, and got home by later afternoon Sunday having felt like I spent enough time in each room, even visiting a few of the rooms a number of times to compare.

So, let's have a peek at some audiophile eye-candy and consider the goods out on display this year. Let's be honest, one of the most important specs whenever doing any shopping is the asking price. Unless specified otherwise, all prices are in USD.

The show ran from September 6-8, 2024 at the SeaTac DoubleTree Hilton which is the same as in previous years. I spent the 7th and 8th "hitting the rooms". Let's go!

SUMMER MUSINGS: On the perils of subjective opinions in High-End Audio (dCS v. GoldenSound).

Every once awhile here in audiophile-land we see our share of drama.

There was MoFiGate a couple years back when vinyl collectors panicked about DSD256 data corrupting their precious analog remasters, Tekton (Eric Alexander) v. Erin recently due to legal threats for calling into question a speaker design, we've seen silly hyped Pono/Neil Young claims a decade ago, and of course the painfully prolonged MQA episode which was just a mess (as summarized years ago).

Well, in the last week we have something a bit different; the dCS v. GoldenSound lawsuit threat due to unhappiness about a YouTube DAC review from late 2021. I'm not going to rehash the stuff here because there were clearly many missteps in dCS's communications as explained in GoldenSound's video and here's the dCS response where the company "fully acknowledge that some of the emails shared by GoldenSound were unacceptable and we addressed and acknowledged this in subsequent communications".

I trust they'll figure it out between the various players on the two sides. As with the domestic conflicts of others, I'm not particularly interested in the details as to who said what unless personally involved. Likewise, some of the technical details regarding the external clock, DSD resampling, seem to be side distractions from the concerns around the review; no need to spend time with these minor digressions.

Instead, I was more curious about that original dCS Bartók DAC/headphone amp YouTube review by GoldenSound that came out on December 31, 2021. What was it that made dCS or their representatives so upset? Is there something about the review itself we can/should learn from?

"High-End" DAC Blind Listening Results - PART III: Subjective Descriptions

In this last part of the "High-End" DAC Blind Listening Survey write-up, (see Part I, Part II) let me document the more qualitative aspects of the responses I received from listeners. These come from the comments section where listeners described what they heard. You'll also get to see in context some of the descriptions of the hardware used in the evaluation.

Comments will be posted verbatim other than removing any identifying information and names unless the person specifically says it's OK. Not all comments are posted, only the ones with a fair amount of subjective experiential content or description of evaluation procedure. It's interesting knowing which city/country some folks are from so I'll leave that information if mentioned.

So as not to neglect those who said they heard no difference (yet I know many spent a good amount of time on the test), let's start with that group of respondents... I'll add some comments/responses along the way.

"High-End" DAC Blind Listening Results - PART I: Devices Unveiled!

The time has come friends. Over the last 6 weeks, I've been collecting the data from the 2024 "High-End" DAC Blind Listening Survey. The procedure I think is already well described in that test invite post so I won't spend time here recapping that. Thanks for everyone who participated in the blind listening!

As with many blind listening tests, unless it's literally obvious, I know it's not easy to flip back and forth and it's very common after a few A/B/C switches to second-guess oneself! I certainly appreciate the time that participants spent downloading the >500MB file, getting it onto your listening devices, and the listening itself.

For this post, let's talk about the test, some rationale, and let me unveil the 3 DACs that were used.

On Stereophile's "Dolby Atmos: A Bleak Shadow?" - really? 🤔

I saw Stereophile's "Dolby Atmos: a Bleak Shadow?" article the other day. Honestly, I found it a bit irritating. The ideas seemed poorly contextualized with little background or meaning for what I imagine would be the average audiophile reader. It basically consisted of hearsay-level cherry-picked concerns as if these are significant (including that title).

Let's be clear about this. It's not like any of us must or even should love Atmos or multichannel. We can easily get through a lifetime of music enjoyment with 2-channels. Even though I like and even prefer multichannel/Atmos for many of my albums, it's just an option for those like myself who want to explore the surround-sound music experience as a superset of modern audio reproduction technology. Some artists and audio engineers these days are also exploring the extensive flexibility and ways to best create the mix. So if a traditional audiophile magazine believes that staying at 2-channels is all that's needed, well that's fine. But one doesn't have to write articles that seem to be trying to induce some kind of emotional response, stirring intrigue or concern even in just that title. (These days, sound bites and headline titles might be all that many pay attention to.)

So what do you mean by "bleak shadow", Mr. Lindberg (as reported by Jim Austin)? Are we talking just about numbers like bit-rate going down when a lossy stream is delivered to the consumer, or are we implying that sound quality changed significantly in a negative, "bleak", way? If it's only bit-rate reduction, that's totally fine, isn't it? Since the consumer isn't keeping the data, there's no point wasting network bandwidth! Streaming services like Netflix or Disney+ all stream lossy video and audio. Many customers, I'm sure including discerning ones, will not complain if they understand the nature of the technology and the quality limits depending on how it's consumed.