Most people who now listen to tube amplifiers began with a transistor amp, and know from experience that a tube amp of a given measured power output sounds louder than its nominally identical transistorized equivalent. The unofficial consensus is that you need two to four times the transistor power to achieve the same loudness as you would using tubes. In other words, given the (subjectively) undistorted sound level a 25W (footnote 1) tube amplifier can provide, if you want the same loudness from solid-state technology you would have to replace it with at least a 50W transistor amp (footnote 2).

Most people who now listen to tube amplifiers began with a transistor amp, and know from experience that a tube amp of a given measured power output sounds louder than its nominally identical transistorized equivalent. The unofficial consensus is that you need two to four times the transistor power to achieve the same loudness as you would using tubes. In other words, given the (subjectively) undistorted sound level a 25W (footnote 1) tube amplifier can provide, if you want the same loudness from solid-state technology you would have to replace it with at least a 50W transistor amp (footnote 2).

Most people who now listen to tube amplifiers began with a transistor amp, and know from experience that a tube amp of a given measured power output sounds louder than its nominally identical transistorized equivalent. The unofficial consensus is that you need two to four times the transistor power to achieve the same loudness as you would using tubes. In other words, given the (subjectively) undistorted sound level a 25W (footnote 1) tube amplifier can provide, if you want the same loudness from solid-state technology you would have to replace it with at least a 50W transistor amp (footnote 2).

We <A HREF="http://www.stereophile.com/news/10339/">reported last year</A> about the new direction that <A HREF="http://www.bang-olufsen.com/">Bang & Olufsen America</A> has taken in distributing its products: the company has recently opened a series of branded BOA stores around the US. The strategy seems to have paid off. The company reports increased sales of more than 60% in the first quarter of its current fiscal year, and claims that individual shops reported an average sales increase of 20%.

Choice is good, or so would go the common wisdom. But as John Atkinson points out in "<A HREF="http://www.stereophile.com//asweseeit/270/">The Crazy You Get from So Much Choice</A>," when applied to diapers and DVD-Audio, choice can quickly develop into a nightmare in which comsumers simply walk away from the shelves, unable to make a decision. Will DVD-Audio suffer such a fate?

E<I>ditor's Note: This is Part Five of a six-part series from reader Herv&#233; Del&#233;traz of Switzerland, who is chronicling the development of his DIY (do-it-yourself) audio amplifier. Part One of the series is <A HREF="http://www.stereophile.com/news/10825/">here</A&gt;, Part Two is <A HREF="http://www.stereophile.com/news/10832/">here</A&gt;, Part Three is <A HREF="http://www.stereophile.com/news/10839/">here</A&gt;, and Part Four is <A HREF="http://www.stereophile.com/news/10844/">here</A>.</I&gt;

Software giant <A HREF="http://www.microsoft.com/">Microsoft Corporation</A> has acquired <A HREF="http://www.hdcd.com/">Pacific Microsonics, Inc.</A> (PMI), developer of High Definition Compatible Digital (HDCD) technology. The deal was announced in a joint press release issued September 18. Financial details were not disclosed.

An unusual tropical rain welcomed the <A HREF="http://www.aes.org/">Audio Engineering Society</A> to its 109th gathering, held at the Los Angeles Convention Center September 22&ndash;25. Audiophiles may breathe a collective sigh of relief to learn that the Super Audio Compact Disc is getting a big push, not only from corporate parents Sony/Philips but from studio-equipment makers, consumer-electronics companies, and&mdash;perhaps most important&mdash;music labels.

Italian audio journal <I>Fedelta' del Suono</I> (Sound Fidelity) has honored American startup <A HREF="http://www.redrosemusic.com/">Red Rose Music</A> with "Product of the Year" awards for the company's Model 3 preamplifier and Model 2 power amp. The award is especially noteworthy in view of the fact that the monthly publication, based in Terni, Italy, does not normally f&#234;te products from new companies.