Tube Preamp Reviews

We audio writers have our niches. Mikey loves analog, Artie likes to play with horn speakers and assorted oddball British kit, and I really enjoy reviewing affordable speakers. There's something exciting about hearing the fruits of the labors of a creative designer who's applied his talents to meet a stringent price point and created a speaker that can entice into our hobby the financially challenged music lover.

I'm not sure what motivated me to read the owner's manual for the Audio Valve Eclipse, but I'm glad I did: As it turns out, this line-level preamplifier has at least one distinctive feature that I would have missed otherwise.

In red letters on the first page of Chinese audio manufacturer Audio-GD's website are these words: Wisdom in mind, enthusiasm at heart.

I like this goodwill greeting because it sets a mindful tone. I presume that sentiment was issued by one Mr. He Qinghua, because farther down the page, it states, "All Audio-GD's products are designed and developed under the leadership of Mr. He Qinghua." When I began my auditions, I took this salutation as an advisement, making it my plan to study Audio-GD's Vacuum HE1 XLR line-level preamp with as much wisdom as I could muster and the enthusiasm of high expectations.

If any single link in the audio chain should be free of sonic personality, it's the preamplifier. Though a preamplifier's basic job description is "source selector with volume control," from hi-fi's earliest days preamps have been the designated dashboard: the more dials, switches, and lights, the better. All that control came at the cost of quiet, transparency, and tonal neutrality. Still, the quixotic quest for the mythical "straight wire with gain" continued to lead to minimalist designs, including impractical unbuffered "passive" preamps, in which cable length, thus capacitance, affected frequency response.

It's been 10 years since Balanced Audio Technology (BAT) introduced their first products: the VK-5 line-stage preamplifier and the VK-60 power amplifier. (I reviewed">http://www.stereophile.com/tubepoweramps/766">reviewed both in the December 1995 Stereophile, Vol.18 No.12.) The success of these and other BAT products has allowed designer Victor">http://www.stereophile.com/interviews/767">Victor Khomenko (the "VK" of the model designations) and partner Steve Bednarski to quit their day jobs at Hewlett-Packard; they were joined by Geoff Poor as a partner to handle the sales end of the enterprise. BAT's current lineup includes several preamps, phono stages, a CD player, and tube as well as solid-state amplifiers. The top of BAT's preamp range is the VK-51SEhttp://www.stereophile.com/tubepreamps/1103bat">VK-51SE;, which costs $9000; their top tube power amp is the VK-150SE">http://www.stereophile.com/tubepoweramps/536">VK-150SE monoblock ($17,000/pair); if you want their best phono stage, the VK-P10http://www.stereophile.com/phonopreamps/871">VK-P10; will set you back $8000.

I suppose that most high-end designers dream about making a Statement Product—their best effort, without regard for price. Victor">http://www.stereophile.com/interviews/767">Victor Khomenko, majordomo of Balanced Audio Technology, got the bug and came up with the VK-50SE. This hugely full-functioned line-stage preamp derives its Special Edition (SE) moniker from the eight hot-running, super-hush-hush Russian 6H30 Reflector SuperTubes that populate the circuit board.

Rudyard Kipling said that "never the twain shall meet." He was speaking of East and West, but in the world of audio, his adage has most often been applied to what has been the traditional chasm between the sounds of tubes and solid-state. Tube advocates thump the tub for the timbral and spatial glow, the absence of harsh, odd-order harmonic distortions, the harmonic completeness and holistic spatiality that only fire bottles can provide. Solid-state advocates point out the superiority of their preferred gear in terms of bass depth, power and control, low noise, and ultimate detail resolution. That chasm between the characteristic sounds of tube and transistor has narrowed appreciably in the latest generations of gear, as each type of circuit has become capable of embodying some of the other's trademark characteristics. But between the camps, friendly competition continues.