MEASUREMENTS: Topping DX3 PRO V2 (LDAC version) - plus frequency/amplitude stepped sine measurements, a quick look at the 8kHz USB PHY packet noise, and AirPods Pro "Spatial Audio" coming...

So I got another DAC here at home - purchased through usual retail channels of course :-).

The Topping DX3 PRO (~US$220) is a device meant for those who want wired (S/PDIF TosLink, Coaxial, USB) as well as flexible Bluetooth 5.0 wireless input. There are 2 versions of the DX3 PRO out there - the earlier version reviewed/measured at Audio Science Review by Amir and the newer one which I have here with LDAC support (Sony-developed "high resolution" Bluetooth CODEC, also measured by WolfX-700) released in late 2019.

At some point, I figure it would be interesting to compare how the various Bluetooth codecs perform since this device can accept the lowest common denominator SBC, plus AAC, aptX, aptX-LL (Low Latency), aptX-HD, and LDAC audio - about as broad a range as I've seen among Bluetooth DACs (here's a good primer on these acronyms).

For today, let's examine the device's standard DAC performance and run it through my typical procedure with a few new measurement variants to see how it performs.

MUSINGS/POLL: A lifetime of digital audio storage? Enterprise / Data Center hard drive update.

For this week's post, I thought I'd spend some time talking about music storage, a recent upgrade, and some thoughts while reviewing my own music collection. A potpourri of observations and ideas, ending with a little poll...

A few weeks back, I saw this "extreme" server system described on Audiophile Style. I certainly agree that a machine like this is very much extreme for simply audio playback or as a music media server (presumably it will not even be used for something more demanding like a higher bitrate 4K/HDR movie/video player)!

What got me thinking about my own server system was not whether one needs something like this for "good sound" - of course one does not. I thought it was very cool though that the machine is capable of such a large amount of SSD storage - up to 24TB. Basically, what they're doing is putting up to 3 ASUS Hyper M.2 X16 PCIe (~US$60-70) cards in the machine. The user can then install up to four M.2 SSDs within each card (a single 2TB WD Blue 3D can be had for about US$230 currently, 2TB WD Red for around US$280). So with each ASUS card filled up, we have up to 8TB SSD storage, and 3 of these populated ASUS card results in that 24TB potential.

BLIND TEST RESULTS Part III: "Is high Harmonic Distortion in music audible?" Subjective Descriptions

As we've seen in Part II last week, based on the preference data, there was a pattern for the respondents to this blind test to choose the samples with lower added distortion as sounding "better". I believe this is encouraging for audiophiles who seek "high fidelity" and "accuracy" in the reproduction of music. It's a demonstration that correlates objective levels of distortion with a subjective preference.

Today, as we end off the write-up for this blind test, let's consider the subjective descriptions of what was heard by the respondents. Words describing experience and feelings can be difficult and imprecise, but by correlating how listeners expressed themselves with knowing how they ranked the samples, perhaps we can appreciate the scope of adjectives used when people listen to content with significant harmonic distortion...

BLIND TEST RESULTS Part II: "Is high Harmonic Distortion in music audible?" Respondent Results

Having described the study and procedure last week in Part I for this most recent online blind test, let's continue by looking into the results from the 67 unique respondents. For this post, we will focus on the "objective" results based on the data. As I have done in previous tests, in a follow-up post, we'll have a look at the "subjective" descriptions of what respondents perceived.

We'll start as usual with some context into the respondents' demographics, we'll then proceed to examine the sound systems used by the respondents, and from there, look at their blind listening submission results to see if harmonic distortion correlated with preferences around perceived "better" or "worse" sound quality...