Tidal Prisma Preamplifier and Ferios Monoblock Power Amplifiers

Transparency Incarnate

Equipment report
Solid-state power amplifiers,
Solid-state preamplifiers
Tidal Prisma Preamplifier and Ferios Monoblock Power Amplifiers

It’s become a cliché for high-end audio manufacturers to claim that their products are so transparent that they “faithfully communicate the artist’s expression.” Although many designers aspire to this lofty ideal (or proclaim to), very few actually realize electronics that are truly transparent, or as transparent as today’s components can be. To be sure, there are many great-sounding preamplifiers and power amplifiers, but all have a particular sonic signature. That signature could even be one area of sonic performance that stands out as being better than other aspects of the amplifier’s qualities. It’s not a bad thing, but it is a departure from neutrality, and one that defines the amplifier’s characteristic “sound.”

No electronics are perfectly transparent, but the new Prisma preamplifier and Ferios monoblock power amplifiers from Germany’s Tidal are, to my ears, about as transparent and uncolored as electronics get. Their disappearing act goes beyond the cliché of “faithfully communicating the artist’s expression”; they possess a vivid immediacy,conveying a striking sense of hearing back through the playback system to the original musical event. This quality, combined with the pair’s innovative circuit design, elaborate execution, and beautiful build-quality, places them in the upper echelon of today’s best electronics.

Founded in 1999 by Jörn Janczak, Tidal isn’t to be confused with the streaming service of the same name. Rather, Tidal is a designer and manufacturer of a full line of preamplifiers, power amplifiers, a DAC, and some outstanding loudspeakers. One of these speakers, called La Assoluta, sells for a whopping $700,000 per pair (and Tidal has customers for it). Tidal is a company with high ideals and perfectionist standards, not a firm that creates products to a price point or to fill a perceived market niche. 

The company’s three power amplifiers and three preamplifiers are all built to the same uncompromising standard. The Prisma full-function preamplifier reviewed here ($40,000) is the middle preamp in a three-preamp range. Similarly, Tidal makes three power amplifiers, of which the Ferios monoblock ($85,000 per pair) is the middle model.

Looking first at the Prisma, the product is a full-function preamplifier with an integral phonostage. Unlike virtually all full-function preamps in which a phono section is added to a linestage, the Prisma’s phono- and linestages form an integral circuit. This is an important aspect of the design, which I explain in detail in the “Under the Hood” sidebar. The Prisma is at once Spartan and lavish; the front panel has just two controls, volume and a rotary source-selector—no display or lights save for a power-on LED that flashes when the unit is muted. The on/off switch is incorporated in the source selector, further minimizing front-panel controls. Yet the materials, the feel of the knobs, and the finish work give the product an unmistakably upscale vibe. For example, the front panel is made from polished black acrylic that is reportedly seven times costlier than aluminum (and reportedly less prone to storing energy). The plate behind the volume control that looks like chrome is actually a solid block of stainless-steel polished to a mirror finish. The volume knob has a wonderful feel, like a “spoon in a honey jar.” Regrettably, there is no balance control.

 The rear panel reveals that the Prisma’s three line inputs, one phono input, and two pairs of outputs are balanced only—no RCA jacks anywhere. Yes, the phono input is balanced; if you have RCA-terminated phono cables, you’ll need to replace the cable (if your tonearm’s cable is interchangeable) or re-terminate the phono cables with XLR plugs. Another option is using RCA-to-XLR adapters. (A balanced phono connection can be a bit confusing, so I explain how it works in a second sidebar.) The phono input is only compatible with moving-coil cartridges, and has just two gain settings, selectable from the front panel (“Phono Lo” and Phono Hi”). The high-gain setting provides an additional 10dB of output, although neither gain value is specified. (The “Phono Lo” setting was sufficient for the 0.45mV output of my Air Tight Opus cartridge.) Loading adjustment is realized with a rear-panel 12-step rotary knob (50 ohms to 2000 ohms). The actual impedance value isn’t indicated on the knob, but Tidal supplies a chart. Any of the three line inputs can be set to unity gain as a home-theater “pass-through” input. The eight-button remote control is, surprisingly for a product of this price and execution, made from plastic rather than metal. 

The Ferios monoblock is rated at 300W into 8 ohms, 580W into 4 ohms, and 780W into 2 ohms. The amplifier is essentially a scaled down version of Tidal’s Assoluta flagship amp, with the same circuit topology, build-quality, and casework, and virtually all the same parts as the flagship, but a smaller power supply and output stage. A polished stainless-steel plate runs vertically through the center of the polished black-acrylic front panel, matching its look with the Prisma preamp. Inputs are balanced only, and the two sets of output terminals are beautifully made custom jobs with solid-silver contacts. RJ-45 jacks allow connection to the Prisma for automatic powering up when the Prisma is turned on. The casework and styling are exceptional. (See the sidebar for technical details on both products.)