Saturday 26 September 2020

MEASUREMENTS: RME ADI-2 Pro FS R Black Edition as DAC.


Well friends, it's time to publish some measurements of my new RME ADI-2 Pro FS R Black Edition ("FS R BE") unit as DAC. For background, refer to the Preview from August and a couple weeks back, I had published results discussing the ADC function.

As you might be aware, since 2018, I've been using the older RME ADI-2 Pro FS ("Pro FS") for ADC and DAC duties in my measurements. It has performed like a champ and in fact, given that the ADC function is almost identical between the two units, there's certainly no reason to retire the "Pro FS" from measurement duties.

What we know is that as a DAC, the "FS R BE" should perform better than the "Pro FS" due to the fact that the internal AKM chip has been upgraded to the AK4493 from the previous AK4490. On paper, this represents a +5dB improvement in SNR and +1dB improvement in THD+N so we're not looking at Earth-shattering differences in specs numbers. Let's see if we're able to measure these differences on the test bench and identify any other changes to the DAC's performance along the way...

Saturday 19 September 2020

As We Hear It: Thoughts from an audiophile friend on assembling his sound system.

Every so often, I have the pleasure of having friends and readers add their thoughts to these pages. The other day my buddy whom I visited at the end of 2019 (a.k.a. "linnrd" online) sent me this discussion piece. Back in December when I visited, I invited him to take the opportunity to write about his equipment and how he came to this interesting collection of gear. Well, he delivered...


A Complex Path to Simple Sound

Audio systems are generally an assemblage of products from different manufacturers. While significant R&D resources go into designing the various pieces that make up a system, it is left to the consumer to deal with the "R&D" of system design from "soup to nuts", as it were. The popular audio press is more oriented to singing the praises of individual components instead of educating and helping the reader actually assemble a decent combination of the aforementioned. Perhaps this a result of whom they view as customer and who as the product. A graveyard visit allows one to see much touted wonders such as Shakti Stones and the green CD marker (Ed: also see Harley's extensive investigation in Stereophile in 2004 amounting to nothing of course), to name just two, with the rotting corpse of MQA lying in wait for a plot (in both senses of the word!). 

Unfortunately, the self-proclaimed experts actively ignore existing knowledge and science and make it extremely difficult to fix this fundamental problem of the spread of misinformation by also subscribing to junk science. In other words, they are really messing up the S:N ratio of information transmission. As Bill Whitlock from Jensen says, reiterated in a recent discussion: "It often feels like an uphill battle to educate in a world of marketing deception and self-appointed experts."

Saturday 12 September 2020

MEASUREMENTS: RME ADI-2 Pro FS R Black Edition as ADC.

About a month ago, I posted this preview of the RME ADI-2 Pro FS R Black Edition AD/DA converter. It has been a wonderful month of simply listening to this device without a care around performing measurements. For listening, I have it set up as per the image in my sound room with the Raspberry Pi "Touch" running RoPieee previously discussed.

So far, from a subjective perspective, it has been a joy to listen to music with this machine.

Alas, as a "more objective" audiophile, it came time to have a look at the performance for this device to check if I'm missing any significant limitations. Over the years, I've discussed limitations to human hearing as well as the idea that many of our audio electronics these days have surpassed human auditory perception such that while measurements of DACs or amplifiers can show limitations, often these are beyond the resolution thresholds of human hearing/perception. Remember that while not all measurable anomalies need to be chased after when the goal is simply to be able to enjoy music, technical "ideals" are useful for devices one may want to use as a "reference".

So to start, today let's just focus on the ADC side of this RME device. Remember that the RME ADI-2 Pro FS R Black Edition (again, let me just call it the "FS R BE" for short) is an evolutionary step from the ADI-2 Pro FS ("Pro FS") that I started using 2 years ago. Consider this article as building on some of what we already know about the Pro FS as an ADC from 2018 with requisite repeated tests comparing the two machines and using today's software.