Digital Processor Reviews

For music listening circa 2024, streaming is both the present and the future. Physical formats are still around, and they are still the best choice in some cases, as with deluxe reissues of beloved albums, which may add value with extra live performances, full-resolution surround sound, and other perks. The niche vinyl market continues to thrive, and that business model obviously works for releases of a few thousand copies. (It also works, apparently, for releases of hundreds of thousands of T-Swift platters to be displayed on shelves and hung on walls.)

But facts is facts: Streaming is now the only mass medium for listening to recorded music—the primary carrier for music—and has been for a few years now. According to RIAA statistics, the crossover year was 2016. That's when, in revenue terms, streaming outpaced physical formats. By 2022, the latest full year tabulated, streaming accounted for 84% of US recorded-music revenue.

So what's a long-time audiophile, born into the analog world, with strong roots in physical media, supposed to do?

One thing that interested me about the StormAudio ISP Evo is that, despite its obvious hi-fi function, it's more like a computer than a typical "prepro." While it does offer a few "legacy" analog inputs, it is for the most part all-digital, input to output, including network connections on both ends. Consequently, it is less likely to leave sonic fingerprints on the music than devices that convert digital to/from analog or modulate their signals with active amplification or attenuation. It is notable that, despite its audio function, the Storm completely lacks traditional audio specifications—distortion, dynamic range, and so on.

Yes, that aspect of the product was appealing, but the real trigger for me was that when I began this review, the StormAudio ISP Evo was the only consumer device to fully incorporate the latest version of Dirac Live Active Room Treatment (ART).

I can roll out of bed and install a $10,000 phono cartridge while finishing my coffee, but I postpone DAC installations until I am in the exact right mood to handle the potential stress—especially DACs with a touch screen and a complex menu. To my delight, Ferrum Audio's new Wandla digital converter was completely stress-free to install. It took only minutes to connect the USB-C cable, the Cardas Audio Clear Beyond interconnects, and 24V DC power adapter.

Connecting the power adapter caused a power-switch symbol to appear on the front panel touch screen. The moment I touched it, I smiled like the Cheshire Cat, because I saw a USB-C symbol, a loudspeaker symbol, three dots in a box, and a volume control bargraph. That told me the Wandla recognized my chosen input and was waiting for a signal. All that remained was for my Roon Nucleus+ server to recognize and enable the new DAC, which it did without prodding or reprimand. For me, that was a wow moment, a good start to what promised to be an interesting review.

I've been running a 5.1 system for years. Recently, I expanded it to 5.3 with the addition of two more subwoofers. This system is manageable with one of my eight-channel DACs.

Even more recently, I dipped my toe into Dolby Atmos, which made it necessary to lash up at least four more channels. That was a big problem, since neither JRiver nor Roon can support and sync more than one output device at a time, and the multichannel DACs I already owned tap out at eight channels.

I turned to the Arvus H2-4D Renderer, which offers 16 channels of digital output over AES3 and 16 channels of balanced-analog output. This worked, but piping everything through the Arvus meant forswearing DSP, including DiracLive. I really needed a DAC with at least 12 channels.

The Merging+Hapi has been around for years...

To misquote Morrissey, some knobs are better than others. The Manley Neo-Classic 300B amplifiers that I've been listening to, for example, have a knob marked "feedback" that goes from 0 to 10. I've learned so much from using it that I've come to believe that if your amp doesn't have such a knob, it should. You see, the higher you set this control, the better the amp will measure. Applying more global negative feedback to these amps lowers their nonlinear distortion and noisefloor, increases their bandwidth, renders them less sensitive to the speaker's impedance variations and otherwise makes them more stable and efficient. In fact, by applying lots of feedback to an amplifier, it's possible to reduce distortion to barely measurable levels.

So what's the problem? Well, a few turns of the knob suggest that negative feedback isn't as useful as it appears on paper.

Stereophile writers and website commentors often speak to the topic of the ongoing rise in retail pricing at the upper levels of the hi-fi market. Companies producing cost-no-object designs make regular appearances in the hardware reviews published here. However, a countervailing vector is also at play in the consumer hi-fi sector: a trend toward bringing to market products that are smaller and more economical than the competition while offering an ever-increasing variety of features and continually improved performance, notably in terms of measurable specifications.

This dialectic can sometimes play out within the same company. Abbingdon Music Research (AMR), which is based in Southport, UK, was founded in 2000. At first, under the AMR brand, the company focused on high-end audio component separates with price points toward the upper end of the spectrum. The world has a way of intervening, though, even with the best-laid business plans. AMR Director Vince Luke describes in a video how his company made a deliberate choice to "pivot from high end to low end" following the financial crash of 2008. AMR's iFi Audio division debuted at the Rocky Mountain Audio Fest in 2012, offering a handful of portable products. They were a hit. The iFi line has since expanded to include more than 50 designs, and new products are introduced with impressive frequency.