The Luxury of Sound and Time: Audiophile products, the Rolex and Timex Analogy.

Left: This certified authentic Used Rolex Cosmograph Daytona Watch, with the Model Number: 126598TRU, has a Yellow Gold/Diamonds 40 mm Round Case with Screw Down Crown and a Gem Set. This Men's Rolex Cosmograph Daytona has an attractive Diamond Pave Dial with Gems Dial Markers. The certified Swiss tested Rolex Automatic Movement will keep perfect time for you. The elegantly designed Rolex Yellow Gold with will look great on your wrist.

Right: Timex Men's Waterbury Classic Chrono 40mm Stainless Steel Quartz Dress Watch with Leather Strap. Reviewed to be one of the best well-priced mecha-quartz watches.

If we plug in the phrase "Rolex vs. Timex" into Google, we'll see that there have been a number of articles written about this topic aimed at wristwatch hobbyists that compare and contrast things like history, the products, features, and prices (like this). For the purpose of our discussion here, the actual brands are of could not too important; these are mere archetypes - Rolex the Swiss brand that caters to the prestige luxury market, while Timex is an American company (originally started as the Waterbury Clock Company in 1854, these days American-Dutch) known to produce mass-market time pieces for the "common man"; to satisfy the needs of kids, the athlete, and yes, even dipping its toes into the luxury market though nothing like the Rolex brand price-wise. As per their classic slogan suggesting the device is meant for the conditions of daily life, the Timex - "It takes a licking, and keeps on ticking."

Over the years on this blog, I've touched on the ideas behind luxury products - here and here for example. We've also discussed the wine-tasting pursuit compared to audiophilia, but I think there is an even better analogy we can make when we look at something like the wristwatch collector (horophile) hobby. Since both audio products and watches are products of technological evolution, I believe there are similarities when it comes to the trajectory of these products, the industries behind their production, the consumers who buy them, the way they are portrayed in advertising (including in reviews) and social sentiment.

So grab a comfortable seat, maybe get a nice beverage, let's take some time to think and discuss...

A look at the music library: How much DAC intersample overhead is enough? True Peak analysis of genres in an eclectic digital collection.

In a recent article about Linn DS streamers, I touched again on intersample peaks ("True Peaks") as I measured the DAC hardware. In the comments section, there was further talk about this topic so this got me thinking over the last few weeks to spend some more time on this but from a different angle.

For those who are not aware of what "intersample peaks" are, recall that DACs implement filters to ensure accurate reconstruction of the waveforms (unlike the jagged-looking NOS DACs which some audiophiles still subjectively appear to prefer). Typically this is done through oversampling whereby 44.1kHz (ie. CD samplerate) might be increased by something like 8x (352.8kHz) while applying a low-pass filter that cuts off content beyond the 22.05kHz Nyquist frequency. The DAC will interpolate to create those extra upsampled datapoints. In this DSP process, some of the reconstructed "intersample" points might have >0dBFS values. If these "True Peak" values are too high beyond the limits of the digital filter or output level of our DACs, the samples will "clip", resulting in extra distortion in the playback.

For this post, instead of considering from a hardware measurement viewpoint what kind of overhead a DAC can handle, let's consider from the music content side by using a relatively large music library - my library of thousands of albums - and consider just how much overhead peak we might find and "need" based on the commonly-owned music genres in an audiophile's collection.

MUSINGS: nVidia's GeForce RTX 4090. Power Limited Overclock settings. On technological progress into cognitive domains.

For this post, I thought I'd explore technological progress in the computing space. While I speak mainly about audio topics in these pages, I hope this post gives you an idea of the broader technological progress happening around us.

As per the image above, I've updated my workstation graphics card to a Gigabyte GeForce RTX 4090 Gaming OC. This card is truly a beast, covering 3.5 slots in the computer thanks to the extra vapor cooling chamber. [Related to this card is the slimmer Gigabyte GeForce RTX 4090 WindForce V2 that "just" takes up 3 slots.]

Years ago in 2017, I spoke about my GTX 1080 used in the game machine of that time. Since then, it's obvious that technology has moved forward very substantially! Every couple years has seen a new generation of graphics cards churned out by nVidia typically with AMD following suit and these days Intel making headway with their more budget-friendly ARC line.

With each iteration, we're seeing objective improvements in computational ability and physical characteristics like the shrinkage of the transistor "process" from 16nm for the GTX 1080 down to the 5nm (near limits of silicon) in the RTX 4090 today. With the ability to fit more transistors into a smaller area (higher density), the number of parallel computational cores has increased from 2560 shading cores (also known as CUDA cores) in the GTX 1080 to 16384 units in the RTX 4090, a 6.4x increase in this one metric alone; not to mention the addition of new features like the Tensor cores (high speed, mixed precision, high-dimensional matrix multiplications) released in the RTX 20*0 generation, important in deep-learning tasks.

MEASUREMENTS: USB Isolation with Nobsound ADuM4160 device and hi-res DAC. The world these days, and the audiophile microcosm.

 

After writing about very high resolution measurements with the E1DA Cosmos ADC last week and touching on basically "state of the art" fidelity like the Topping D90SE, for this week's post, I thought it would be good to talk about something more "fundamental". Often spoken of among audiophile tweakers but rarely have I seen evidence of actual value/effect for many of these devices.

Before I begin with this post or even show you anything, let me just say that I do not believe audiophiles need USB isolation for use with devices like DACs unless you know you have noise issues. I think we've all see indiscriminate suggestions that audiophiles need all kinds of noise filters and isolators (like this, or this). Sometimes these things cost quite a significant chunk of change compared to the downstream device (like DAC) itself!

Over the years, I have tried out a number of USB DACs with computers and simple streamer devices like the Raspberry Pi. With a normal set-up, I cannot say I have ever heard an issue with any of the various decent DACs I've tried. Likewise, measurements already suggest that in general there are no major noise issues with at least reasonable modern devices.

However, there are times when the system is complex enough where indeed you do see ground loops and noise like the 8kHz USB PHY noise pop through. A couple months back, I showed you some of this when we took the rather useless AudioQuest JitterBug FMJ for a spin in some of these situations! Today, let's look at the effect of that little inexpensive Nobsound ADuM4160 USB Isolator (typically can be purchased for <US$25) you see in the picture above.