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.

1kHz Test Tone: Does increasing the number of PCM values really matter? And Stereophile's "still listening" to the community (so they say).

Hey there audiophiles, lots happening in life to keep me busy these days as we enter summer 2025, so let's do another little follow-up of a topic based on reader comments.

In the previous post, there was a comment by Mister MB about the 1kHz test tone and the idea that it would be good to use tones that employ more PCM values as quoted from Ken Pohlmann's book Principles of Digital Audio (currently 6th Edition, 2011, from page 81, emphasis mine):

"Digitally generated test tones are often used to measure D/A converters; it is important to choose test frequencies that are not correlated with the sampling frequency. Otherwise, a small sequence of codes might be reproduced over and over, without fully exercising the converter. Depending on the converter’s linearity at those particular codes, the output distortion might measure better, or worse, than typical performance. For example, when replaying a 1-second, 1-kHz, 0-dBFS sine wave sampled at 44.1 kHz, only 441 different codes would be used over the 44,100 points. A 0-dBFS sine wave at 997 Hz would use 20,542 codes, giving a much better representation of converter performance. Standard test tones have been selected to avoid this anomaly. For example, some standard test frequencies are: 17, 31, 61, 127, 251, 499, 997, 1999, 4001, 7993, 10,007, 12,503, 16,001, 17,989, and 19,997 Hz."

Certainly a good point to think about. However, if we look at actual hi-res DACs these days, and the way we're running 1kHz tests to show routinely >100dB SINAD, would we actually see significantly different results depending on how we create these test tones, specifically whether more or less PCM codes are being used in the signal sent to the DAC?

Well, while I still have the Topping DX9 on my testbench, let's have a look at the analog output from the device with a few ~1kHz test tone variants.

Follow-up: Topping DX9 DAC tests. And reduction in the ability to comment on the Stereophile website.

Topping DX9 DAC sitting on Linn Klimax DS/2 which we'll talk about another time.

Hey guys and gals, thanks for the comments and feedback over the years on this blog. It really helps to refine the testing and of course explore broader ideas about audiophilia and what it is we're after in this hobby. I think it's important that we're free to discuss and critique not just the hardware, but also the ideas (including the philosophy and psychology) that "we" as individuals believe in. There's so much unsubstantiated audiophile cultural beliefs out there based on myths such that everything should be up for examination regardless of who says what. It's not unusual to find that audiophile review "high priests" are wrong, and some "heroes" of the audiophile world are nothing more than false prophets.

It's also good to get feedback suggestions on the published measurements, for example in the recent series on the Topping DX9 flagship DAC (based on rare AKM AK4499EQ chip), Nick in the Part III comments suggested that I consider this:

"Hi Archi,

Prior to version 5.40.78 beta rew had a gross error in IMD vs Level plotting, the results were underestimated by about 12 dB. It looks like the version you used has this error.

IMHO there are not enough performance measurements at high frequencies for a complete picture. If still available, it would be very interesting to see THD (without noise) vs frequency performance, accurate THD measurement at 10kHz and wideband fft (without weighting) with a weak signal such as the signal for the DR test.

Thanks!"

Excellent feedback and suggestions Nick, let's focus on checking this out in this post!

Roon in 2025, 10 years on: Sound quality, thoughts, and suggestions. And an increasingly AI-generated Internet.

Notice it has been "10 Years" for Roon as per the top left.
Roon 1.0 was released May 2015.

Obviously, it's impossible to get on all the discussion forum about the myriad subtopics in this audiophile hobby. However, I do get newsletters in my inbox and I see frequently asked questions that inspire many of the topics addressed here.

If we've come across each other on the audio forums (places like Steve Hoffman's site, or Audiophile Style), you'll notice that I often will respond with links to articles on this blog. I've posted more than 600 long-form articles already, the vast majority digging pretty deep into the audio topic. One of my intentions over the years is for this to be a repository of information, articles I can use as "landmarks" when I engage in discussions with fellow audiophiles; how I understand the hobby including big-picture philosophy, psychology, the debates. Contained within these pages are the thoughts, character, understandings of "Archimago the anonymous audiophile from the early 21st Century" with contributions from guest posters. Familiarity with these articles I think will provide a good starting point for "rational audiophiles", without necessarily going too deeply into technical details.

Apart from discussing individual products, broadly, I think we've covered many of the usual issues raised in audio circles already, much of it analyzed with data to seek out the facts, rather than mere opinions. Feel free on the main page of this blog to use the "Search This Blog" widget as I suspect you'll find articles addressing many questions.

So, coming back to a frequently asked question, for this post, let's think about Roon software in 2025 (currently version 2.51 build 1534). In a recent Roon forum newsletter, I saw this question posed by Eric_Pell:

"I am wondering for years why the most expensive app in the world of hifi and high end only has a sound quality which is only ok. If you compare Roon with JPLAY i think JPLAY has only a few people to develope (sic) software and improve sound quality. But here the difference. What is Roon doing to improve sound quality and do they compare with JPLAY or not?"

As It Is. - Guest post by T.S. Gnu.

"His Master's Voice" - Francis Barraud, 1898
(2025 color remastered.)
Original Nipper with Edison cylinder phonograph.

The Journey

We live at a time in history that many consider to be unique. However, this can be said by anyone at any point in history, and not for the multitude of reasons they believe it to be so, but rather due to the unassailable fact that it just happens to be to the only period in time that they happen to be alive. That is... just the way things are. While it may be entertaining for people to write (or read) about something "As We See It" or even "As We Hear It" along with all the pitfalls that come with those points of view, reality only cares about, and I'm anthropomorphizing here, what is — reality doesn't care about how we see it. This phrasing is also testament to how we are ill-equipped (post-modernists more so than others 🙄) to deal with the fact that the Universe is — it simply exists. The Universe is. It is cold (ca. 2.7K). It is indomitable. And it is uncaring of what we see, what we want… even what we are. 

With that foremost in mind, this missive aims to outline what is as far as our little hobby goes, along with a view of the sauntering journey (with a little ambling off the path) to what we discovered when we arrived here, here being the present time. What is presented here is factual information about past events that is verifiable, and with the odd scientific principles that have been verified by mathematical proofs; in addition there will be the odd opinion, which will be clarified to be as such. Readers are free to disagree with the latter and I encourage active engagement on the same.

nVidia RTX 5070 Ti GPU - a look at the lowest-priced version. And imagine, relinquishing "lossless" orthodoxy.

Hey everyone, as usual, every once awhile I'll look at other tech than audiophile stuff. In late 2024, I wrote about the nVidia GeForce RTX 4070 Super GPU and mentioned in that article about the upcoming RTX 5070 Ti and some of the expectations I had about this interesting card in comparison to the previous generation. Well, now in 2025, the new generation is here and as you can see above, I've got one to test out.

The box above is the Gigabyte GeForce RTX 5070 Ti Windforce SFF 16GB model which is probably the lowest-priced "MSRP" version of this class of cards; I got one of these at a local dealer. This is similar to the Gigabyte GeForce RTX 5070 Ti Windforce SFF OC (Canada) I see available online at places like Amazon but you'd save some money with a non-OC model if you can find it. (As usual, check out other brands like MSI, ASUS, Zotac, PNY for comparisons and relative deals.)

The only difference between OC and non-OC that I can tell for the Gigabyte Windforce is that this card is obviously not pre-overclock from the factory and I believe software like Afterburner power limits at 100% instead of 110%. Since I really have no desire to overclock GPUs (if anything, I do the "Power Limited Overclock" thing by pushing up GPU/Memory clocks but lower the power limit), I'm willing to stick with stock speed and tweak if I have the inclination.

PSA: Logitech dropping many Harmony remote support May 28, 2025.

I suppose it was bound to happen at some point.

If you're a user of the Logitech Harmony universal remote controllers, take note that most models will lose support as the Harmony Remote Software is about to be decommissioned by May 28th, 2025. The software requires access to your account online where profiles are stored.

Initially released back in 2001 by Canadian company Easy Zapper, bought by Logitech in 2004, they stopped production of the hardware in 2021.

Part III: Topping DX9 "15th Anniversary" Limited Edition DAC & Headphone Amplifier - DSD, S/PDIF inputs, headphone out, pre-out, and AMPT. And the desire beyond Perceptibly Perfect.

With Raspberry Pi 'Touch' streamer showing album art running RoPieee, and the Topping DX9 VU meters playing, this looks quite nice in the audio rack!

Let's finish up with the last installment of the review/measurements for the Topping DX9 "15th Anniversary" DAC (see Part I, and Part II previously). As we have seen up to this point, it's quite a unique looking DAC and the initial PCM measurements over USB2.0 look great as a modern hi-resolution converter. In Part II I noted that there was an issue with the 176.4/192kHz frequency response that Topping was able to correct quickly with a firmware update. I'll be using the latest firmware 1.23 for the measurements here.

Let's continue then to dive in and explore the objective performance with some of the other main features for this DAC.

Camera upgrade: Sony (Alpha) α6700 mirrorless camera with 18-135mm f/3.5-6.5 OSS kit lens. 🙂

Hey guys and gals, just thought I'd throw in a little something this week not related to audio as I finish some further measurements on the Topping DX9 DAC I've been talking about over the last couple weeks. As I noted last time, I found an unexpected 192kHz frequency response anomaly with the DAC and I know Topping are looking into it. So I figure I'd give it a bit more time to see if they can get an updated fix out before I publish Part III. Always good I think to publish the "freshest" data.

So, this week, let's do a little show-and-tell for my new travel camera - the Sony α6700 APS-C mirrorless camera with its 18-135mm/f3.5-5.6 kit lens (~US$1400 body only, US$1800 with lens).

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.

Part I: Topping DX9 "15th Anniversary" Limited Edition DAC & Headphone Amplifier - build, features, listening impressions & subjective luxury.

As many audiophiles will remember, the well-known DAC chip maker Asahi Kasei Microdevices (AKM) suffered a massive fire at their factory back on October 20, 2020 in Miyazaki Prefecture, Japan. This resulted in a shortage of their chips for awhile until they rebuilt the plant and started offering devices again by the end of 2021.

In June 2021, AKM issued a "last time buy" notification for final stock of a number of their products. This included their top-of-the-line DAC chip, the AKM AK4499EQ which was initially released in January 2019 and had made its way into a number of devices over the ensuing couple of years. By later 2021, some devices like the HiFi Rose RS150 had to transition to ESS. With 4 channels, a published THD+N of -124dB (mono mode), 137dB SNR in stereo (140dB mono), DSD "direct" (volume bypass), this chip remains a formidable converter even in 2025 with newer generations of AKM and ESS chip DACs. While audiophiles and manufacturers like to talk about discreet DACs like R2R stuff or custom "Ring" DACs, or DSD-processing DACs (like Meitner products or Playback Designs), while I'm sure they sound great, there is no evidence that these are capable of achieving better objective resolution than state-of-the-art converter chips from semiconductor companies with significant R&D resources.

For comparison, based on company specs, the current premium DAC chips are ESS's ES9039PRO rated at -122dB THD+N mono, and 140dB SNR mono. And AKM's current flagship, the 2-channel AK4499EX DAC released in 2021 listed as THD+N -124dB and SNR 135dB stereo (138dB mono). The AK4499EQ as a 4-channel DAC is a much more complicated chip than 2 AK4499EX's because it also incorporates the sigma-delta modulator internally while the AK4499EX needs to be fed 7-bit modulator data at 5.64/11.29MHz from a separate source like the AK4191EQ ΔΣ Modulator!

So, basically, as a single chip, the discontinued AK4499EQ after only about 1.5 years in production, remains the highest performing device among its peers after all these years; on paper at least.

And that's why I bought one of these for my system - the Topping DX9 "15th Anniversary" Limited Edition DAC & headphone amplifier (US$1299, CAD$1900, depending on tariffs you might do better ordering from China through AliExpress):

This is Topping's flagship DAC, released in late 2023. It's said to be limited edition due to the restricted number of DAC chips; I connected with Topping and was told in total they made about 1800 units.

I bought this unit from the usual retail channels and have no affiliation with the company.

Multichannel/Atmos 3D Audio Walkthrough. The idea that DACs sound about the same. Countercultural & honest audiophiles?

Hey audiophiles, I've been wanting to do this for awhile now. Back in 2021 when I wrote about "Spatial Audio" music streaming on Apple Music, in the back of my mind I was thinking it would be pretty cool to not just listen to the music and consider whether this kind of content is worthy of audiophile exploration, but to actually fire up a DAW (digital audio workstation) and play around with Dolby Atmos myself to create a little something that I can also use as a demo or to help with set-up in my own room.

Nothing too fancy of course since the intent is to demo spatial capability rather than wow the listener with overly complex sounds or movements. It's also a fun way for me to learn how to use the software and to go a bit deeper into 3D audio - beyond just expressing opinions on the consumption side.

So, over the Spring Break with a little more time available, I bought a copy of DaVinci Resolve Studio 19 (currently US$300) and got to work on figuring out how to author some 3D audio content. The price is very reasonable for such a powerful piece of software which I plan to use in other audio/video projects. Other packages that allow Atmos audio mastering include Avid's ProTools, Steinberg's Nuendo and Cubase, Ableton Live, Apple's Logic Pro and Final Cut Pro.

Once I figured out how the Fairlight "audio console" module in DaVinci Resolve worked and got the immersive pieces authored, a friend who works in audio professionally helped with the Dolby Media Encoder (US$400/year subscription) side to bring the track over to Dolby Digital Plus / EAC3-JOC, TrueHD-Atmos, and AC-4 IMS.

MUSINGS: Trust, empirical testing, and evidence in the Audiophile hobby. And the Double Blind Test (DBT) strawman argument.

For this post, let's spend a little bit of time thinking about "levels of evidence" in audiophilia. This is important because it helps determine how we gauge the veracity of the articles we read and how we build confidence as we create our own internal models of the topics covered in this hobby.

Inevitably, if we stick around this hobby of audio gear and products long enough, we'll come across the abbreviation 'DBT' - that dreaded Double Blind Test; that seemingly ultimate methodological scientific "gold standard" in human research to tell us whether an intervention or change in our systems actually resulted in a worthwhile difference.

But do audiophiles actually throw around the comment "You need to do a DBT!" very often? Or insist that "I don't believe that unless a DBT proves it!". The answer is 'NO!'- of course not!

Let's start by zooming out a bit and thinking about the very big picture...

High Frame Rate (HFR) movies: time to overcome resistance? Also, on anachronistic nostalgia. And why I rarely go to movie theaters these days.

This week, indulge me in staying a little longer with discussions on the video theme; since I view audio and video technologies as members of the same family, there will be references and detours made about audio in this post.

Although I think 4K is plenty of spatial resolution already for home use (discussed years ago at the advent of UHD BluRays), there is one obvious way to increase the perceived resolution of video playback - improve the "time domain" performance.

While basically everything about motion picture technology has evolved - aspect ratio changes from 4:3 (silent film) to widescreen, frame sizes (35mm various forms, 65/70mm, various digital sensor sizes), B&W to color, higher effective resolution, transition from analog film to digital - isn't it amazing that the cinematic framerate has remained at a mere 24fps, and commonly 180° shutter rule for motion blurring (more geeky testing here)? Since the dawn of the "sound film" in 1926 - almost exactly a century ago! 

High Frame Rate (HFR) movies - movies that were filmed and projected at more than the "cinematic" 24fps - typically 48fps or 60fps - have been simply uncommon for feature presentations to this point. Perhaps reminiscent of multichannel music which had its starts and misses over the decades (eg. 4.0-channel quad back in the '70s), HFR also had a time in the '70s and early '80s when the company Showscan was trying to achieve higher image quality with 65-70mm film at 60fps. But like quadraphonic audio, the technology of the day wasn't really good enough for practical, economical, trouble-free high-fidelity visual reproduction.

Imagine what kind of physical demands would have been necessary for this. Showscan ran the film at 4.68ft/s or 281ft/minute! Clearly a costly endeavor (estimated $2-3M just for the negatives and processing to make a movie back in the '80s) plus imagine the pounds of film to send out to all the theaters, maintenance needs, plus potential damage to the film after a number of runs. How many showings would have been needed for a decent return on investment?!

No surprise then that full-length films were never released in this format. (Here's an interesting brochure from 1990 of their High Impact Cinema prototype, and their 1987 company prospectus.)

HDMI Musings: high speed cables, data rates, YCbCr color subsampling, Dolby Vision MEL/FEL, optical cables and +5V injection.

Hey folks, for this post, I thought it would be good to dive a little more into the world of AV technologies after discussing the nVidia Shield TV Pro last week. While "classic" audiophile technology (ie. standard hi-fi analog and digital 2-channel stereo without special DSP advancements) has matured nicely already, this isn't quite the case with modern digital video tech. While many (probably most) features have settled, we can see ongoing evolution of the High-Definition Multimedia Interface (HDMI) standard to be mindful of - for example the recent announcement of HDMI 2.2 at CES2025 expanding capabilities well beyond the needs of today.

As usual, it'll take time (years) for this standard to be incorporated into TVs and source devices like GPUs (latest nVidia RTX 5080/5090 are HDMI 2.1b) or something like VR devices being at the forefront of potential generational gains. For more than 20 years, with each significant revision of the HDMI standard, we're seeing doubling of data speed with HDMI 2.2 now aiming at just shy of 100 gigabits-per-second (96Gbps), twice of the 48Gbps bit rate in current HDMI 2.1 products.

This recent update makes HDMI the fastest of all currently-announced consumer Audio-Video connection standards, the one wire that basically does it all - hi-res video (with high dynamic and frame rate), hi-res audio (up to 32 PCM channels at 24/192, with DSD to 8-channel of DSD256), HDCP copy protection, audio return channel, even ethernet (100Mbps).

This level of sophistication (and licensing costs) could make it difficult for small companies with limited R&D capabilities to get in the game with custom designs. This is probably in part why the cottage industry audiophile companies rarely use HDMI other than selling overprices cables (like AudioQuest). Plus frankly, basic 2-channel audio doesn't need the higher technical capabilities anyway (which is basically what Paul McGowan says).

Let's run through a few thoughts about HDMI that might be good to know as general knowledge as tech enthusiasts. I'll provide a few links of interest, touch on tech stuff like color spaces and subsampling, and things you might want to try if you're running longer high-speed HDMI connections and potentially noticing issues.