Digital Processor Reviews

For the past decade or so, I haven't been using a preamplifier. The D/A processors I have been using all have volume controls, so I have been feeding their outputs directly to the power amplifiers. It would seem logical that having nothing in the signal path would have less of a degrading effect than a preamp's input and output sockets, switches, volume control, printed circuit-board traces, and active and passive parts, not to mention an additional pair of interconnects. However, with some of the preamplifiers I have auditioned in my system, there was no doubt that the sound quality improved compared with the direct connection from the digital processor.

The most recent of these preamps was the MBL N11 that Jason Victor Serinus reviewed in July 2021, which was preceded by the Pass Labs XP-32 I reviewed in March 2021, the Benchmark LA4 Kalman Rubinson reviewed in January 2020, and going back even further, the Ayre Acoustics KX-R Twenty I reviewed in December 2014, which was one of the products Ayre released to celebrate its 20th year of operation.

I am now reviewing the KX-8 line preamplifier, which costs $6500 in basic form.

After it was delivered, I weighed the box containing Wattson Audio's DAC-equipped Madison LE Streamer on my bathroom scale. It was hardly bigger than a shoebox. It weighed 8.3lb.

When I opened the main box, I found two smaller boxes. The little brown one contained a fist-sized power supply in a chassis of extruded aluminum, with a label attached that said "AC/DC Hybrid Adaptor" next to a circle containing a sun cross symbol and the words "Designed, Engineered and Built in Switzerland" in capital letters circling its top edge. Below the circle was more writing: "Wattson Audio—a CH Precision company."

The Wattson Madison LE's 2.3lb chassis was inside a larger white box with black block letters saying "Madison." Under that, written in cursive, were the words "Lounge Edition." The L in LE is for Lounge, not Limited as you might expect.

I've reviewed a few DACs but never one this small, light, and elegantly formed.

No fewer than eight boxes, powered by six after-market power cables, comprise my current reference front-end. As much as separate boxes can afford superior isolation and provide far more room for visionary engineers to work their magic, the advantages of a single box, which requires a single power cable and far fewer after-market interconnects, are obvious.

Enter Simaudio's Moon 891 network player/preamplifier ($25,000; footnote 2). Also called a "streaming preamplifier,"it includes a DAC that converts PCM and MQA files up to 32/384 (with 24-bit files upconverted to 32-bit) and DSD files up to 256. It also includes what Simaudio company co-owner Costa Koulisakis describes as "a fully configurable" MC/MM phono stage. Both theoretically and practically, it's an ideal solution for someone with space and/or budget constraints.

In my early years in audio, I witnessed the rise and fall of the AM-FM receiver, first in vacuum tube mono and later in solid state stereo. Some of them grew to be behemoths, supporting multiple inputs, equalizers, dual speaker zones, and powerful amplifiers. When radio sources receded in popularity and with the rise of CDs, cable TV, and DVD, radio receivers were replaced by A/V receivers in the mainstream market.

Today, the ascension of streaming as the conduit for both audio and video content has nudged these, too, from the center stage. One can stream content from the bewildering variety of products with internet access including cell phones, smart TVs, almost any computer, and of course, dedicated streaming devices from the cheap-and-cheerful to seriously audiophile. If your music is on the web or on a NAS, many of these will let you browse for it, find it, and play it.

A few summers ago, I briefly got it in my head that I could become a wine connoisseur. This was due to a very generous and unexpected gift. A local acquaintance had passed away, and his wife wanted to rid her basement of his small wine collection.

I don't know why I was chosen as the lucky recipient, but after stammering half a dozen thank-yous, I suddenly owned about 150 fine wines. A few carried four-figure price tags.

Reliably telling a Pinot Grigio from a Chardonnay isn't part of my skill set. Grape varieties, terroir, vintages? You might as well ask a toddler to become conversant in quantum mechanics. Still, I was intrigued by the bottles and amused by the ridiculousness of the situation. Me, an oenophile? I supposed I could pretend, and I did.

After opening and drinking, with my wife, a 1988 Château Léoville Barton, I wrote an over-the-top review and emailed it to a wine-loving friend for his amusement. "I beheld Hawthorn berries and beef stock along with a suggestion of blonde tobacco. Other than the obvious green walnut, there was a top note of wet Baja beach at dawn, mixing subtly with minke-whale flatulence and a hint of two-day-old scallop innards. Finally, with subsequent sips, I detected the aroma of the well-worn merkin of a Honduran sex worker. All in all, not a bad wine."

Eat your heart out, Robert Parker!

I was at least 40' away when I spied my first dCS Lina stack at CanJam. It was black, sitting conspicuously on a table emitting a strong Space Odyssey Monolith vibe. I can't remember which headphones I used, but I do remember how good it felt to face the stack and experience its startling clarity, showing off the bass end of a piano keyboard with a force I could feel in my shoulders. That impactful piano bass plus the stack's matte-finish, neo-Brutalist façade, and feels-like-cashmere volume control, made a strong first impression.

We all know everything sounds like what it looks like—right? It also sounds like what it's made of, who made it, and how much it costs. Well, the $13,500 Lina D/A converter could hardly look more different or feel or cost more different than the $46,500 dCS Vivaldi. The Lina is dCS's lowest priced streaming DAC, so it has to sound less good than my long-term reference Bartók, or the Bartók Apex I reviewed in Gramophone Dreams #75. That's just logical, right?

When standalone digital/analog processors made an appearance a quarter-century ago, they were limited to the CD medium's 16 bits of resolution—at best. These days, almost every DAC can process at least 24 bits, and many models offer between 20 and 21 bits of real-world resolution. Modern models from Benchmark, dCS, Merging, Mola Mola, Okto, and Weiss illustrate not just the skill of the circuit designer but also that of the engineer who laid out the printed circuit board.

One of the first digital processors I encountered that offered 21 bits of resolution was the Weiss DAC202, which Erick Lichte reviewed in January 2012. Subsequent processors from this Swiss company have consistently performed well, not just on the test bench but also in the listening room.