Stromtank S 2500 Quantum II

 Stromtank S 2500 Quantum 2 is a computer-controlled battery-based AC power source from Germany, equipped with the latest 48V battery and inverter technologies. Substituting the isolation-transformer and PS Audio Power Plant combo in my listening room as the AC source, the S2500Q2 transforms the sonic characteristics of the system in a very fundamental way. The mid-range and low-frequency presentation becomes much more full bodied, yet with tuneful, extended and well controlled bass response. Another impressive improvement is in the expressiveness, degree of realism and extended palate of tonal colors/shadings in vocals and instruments, enabling greater enjoyment of every music genre. Additionally, the background in the soundscape further darkens, allowing previously hidden ambient and spatial information details to stand out. With the unit in place, I also notice much easier differentiation among various recording/mixing techniques in the source material, and any audio equipment powered by it seems to demonstrate more of its true potential. Very pricey yet strongly recommended.

DS Audio DS 003

 The DS 003 incorporates the latest generation of optical transducer technology from the Japanese company DS Audio, and in lab tests has been proved to be built with the highest quality standard. In listening sessions, record after record not only does it further glorify the family traits of background quietness, transient vividness, detail resolution and tonal neutrality, but also have surpassed most conventional cartridges in freedom from mechanical graininess or electronic glare/haze. It is also a definite champion in imaging accuracy/stability throughout the entire audible range. More importantly, the DS 003 has such low level of measurable and perceivable distortion, the illusion of an open-reel master tape being played, or even a live event taking place in the room occurs much more often than any competitor in the similar price range. I am tempted to conclude that, this generation of optical cartridges is now capable of impressing listeners not only with abundant musical information, but also with certain amount of magical and seductive power. Strongly recommended.

Audio─Technica AT-ART20

 AT-ART20 is the latest top-end MC cartridge in production by Audio-Technica. Its relatively high compliance rating requires a tonearm with low effective mass to draw out best performance, otherwise the overall character may lack vividness. In proper working conditions, its uncanny ability to effortlessly depict refined yet realistic texture and harmonics of acoustical instruments, especially strings and keyboards, along with human voices is unsurpassed by competitions at any price point. Bass extension, control and pitch definition is also top notch. Unlike high-end offerings from other brands, ART20 does not impress listeners with in-your-face slams, but with a sonic picture nearly free of any electronic glare or graininess. On the down side, channel separation is measured at a mediocre ~23dB. As such image precision and stage width are not among its strengths.