In the last two years, the available choices in 300B output tubes for one's low-wattage single-ended power amplifier have become an embarrassment of riches. If we include the souped-up versions—which, in fact, deviate from the original 1930s Western Electric (WE) specifications—the number of 300Bs to choose from now includes about 15 different brands and types.
While the DVD Consortium's Working Group 4 (WG-4) is still working on the 0.9 specification for DVD-Audio, Sony and Philips have been silently carrying on work on their Super Audio CD, the consumer implementation of Sony's DSD. The Sony/Philips disc will have two layers, one carrying normal 44.1kHz, 16-bit CD information (and thus guaranteeing backwards compatibility with existing CD players), the other carrying eight channels in DSD format (two for high-quality stereo, six for surround), plus text and/or graphics.
Things seemed to be going well for SACD at the 112th AES Convention, held May 10-13 in Munich. The official news, announced at a Sony-Philips press conference, was that one million consumer SACD players have been sold so far. One large Dutch audio retailer even reported to me that they now sold more SACD players than CD players. The prognosis for SACD is total worldwide sales of 6 million players (in whatever form) in 2003 and 13 million in 2004.
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).