Solid State Preamp Reviews

Choosing a moderately priced preamp has traditionally presented the audiophile with a host of serious problems. Most attempt to be all things to all listeners, expending resources on bells and whistles which would have been better expended on basic performance. Few have anything resembling a decent moving-coil stage. But there have always been a few designers (and companies) willing to expend much of their effort at the "low end of the high end." PS Audio has been such a company. Their new 4.6 preamp, an update and cosmetic clone of the earlier, well-received 4.5, is not at the top of their preamp range—that honor belongs to the 5.5—but it is clearly designed to be more than a price-point product.

Before starting this review of Rotel's Michi P5, the 60-year-old, Japan-based audio company's recent preamplifier design, I thought it appropriate to consider "What is an audio preamplifier? What should it do?" There are plenty of opinions to be found at stereophile.com:

"What a preamp ought to do, apart from changing volume and switching sources, is as little as possible," wrote Stereophile Editor Jim Austin in his 2017 review of the PS Audio BHK Signature preamplifier.

Transparency is a trait we all value in a hi-fi rig, and it's a concept I've long thought I understood. A system that tosses up the illusion of a clear, spacious soundstage, on which you can hear—almost see—all of the singers and/or instruments, from side to side and, especially, from front to way, way back: that's the ticket. Still, although such transparency is a sign that you've entered the realm of fine sound, it's not an absolute requirement. Tonal accuracy, dynamic range, a certain thereness that conveys the emotional heft or delicacy of music—those things come first. Without them, the most precisely delineated soundstage is like an architect's sketch of an oil painting.

Over the years, I have become increasingly impressed by the quality of the audio engineering emanating from Simaudio, which next year celebrates its 30th anniversary. In a world where the US facilities of some well-known audio brands have been reduced to a design office coupled to a warehouse for storing product manufactured overseas, this Montreal-based manufacturer, in order to keep full control over quality and hence reliability, does as much manufacturing as possible in-house, including metalwork, some printed circuit-board stuffing, and assembly. (See my photo essay starting here.)

I first saw and heard SimAudio's Moon amp and preamp at WCES two years back, and something about their aesthetics appealed to me: Canadian ruggedness coupled with a decidedly French panache. I remember that those attributes also characterized the demo's sound, although I can't recall the speakers or the sources involved. At succeeding shows, it gradually dawned on me that the Moon components were the fixed elements in a succession of impressive demos.

Sony describes the $700 TA-P9000ES as "a pure audio multichannel preamplifier equipped with two inputs for 5.1 analog multichannel audio sources, enabling selection, volume control, and amplification." A relay with twin gold-plated crossbars switches the two six-channel sources. Then follows a class-A solid-state push-pull amplifier in discrete configuration. Separate transistors, resistors, and capacitors populate the printed circuit boards. An oxygen-free copper shield surrounds each channel to prevent crosstalk between the channels. In addition, there is a relay-controlled gain stage offering 0, +6, and +12dB amplification.

Sumo is one of a handful of American audio manufacturers dedicated to producing moderately priced products aiming for high-end sound; their most expensive product is the Nine Plus, at $1199 (although a more expensive Andromeda II is imminent). When I heard I was scheduled to review the Sumo Athena, I looked forward to the opportunity. A Sumo Nine (not a Nine Plus, which I haven't auditioned) had been my front-line power amplifier a few years ago. It was an excellent budget amplifier whose only serious shortcoming was its limited 60Wpc power output.