Tube Power Amp Reviews

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.

"The realistic reproduction of orchestral music in an average room requires peak power capabilities of the order of 15 to 20W when the electro-acoustic transducer is a baffle-loaded moving-coil loudspeaker of normal efficiency."

—Peter">http://www.stereophile.com/news/121503walker/index.html">Peter Walker and D.T.N. Williamson, writing in the Journal of the Audio Engineering Society in 1954

One of my best friends is a serious jazz collector with a side interest in good replay gear. The last time we got together over a meal, he asked, "What do you think is really the most important component in an audio system?" He might have added "these days": It's a subject we come back to from time to time.

Leaving aside for a moment the fact that the Wavac SH-833 costs $350,000/pair—

Most of us have at least some taste for gear that jumps out—for audio components whose sonic and musical distinctions are easy to hear from the start. In audio, unlike in the art of music itself, there's nothing wrong with being obvious.

For those who frequent the audio discussion groups on the Internet, the method by which Stereophile selects products for review seems to be a continuing source of fascination and conjecture. Supporters of fledgling manufacturers—whose products these Webcrawlers just happen to own—rail against the rule that products to be reviewed in the magazine must have at least five US dealers. Some suggest that Stereophile's selection of review products is all about catering to advertisers and friends in the industry, a process that seems intended to exclude their favorite products from consideration.

Ah, Brazil...land of coffee, the samba, Pelé, Rio-by-the-sea-o, and tube amplifiers. All right, so perhaps the amplifier connection isn't quite as well-established. But one Brazilian amplifier designer, Eduardo de Lima, has published articles in Glass Audio magazine that are viewed by many as groundbreaking, and his evolving products have been seen at various specialist tube equipment shows. De Lima—president, founder, product designer, and principal owner of Audiopax Sistemas Eletroacusticos—is an electrical engineer who started out designing equipment for a telecommunications company, but since 1995 he's devoted his talents to designing a wide range of audio products, including speakers as well as preamps and power amps.