Category: Tubes

This blog post, focusing on the Leben CS-600 and CS-600X tube amplifiers, began as a thorough introduction to vintage tubes after I bought a Leben CS-600 in 2024. It expanded to cover other Leben Hi-Fi Stereo Company amplifiers, from early models to their latest tube-based products, with a focus on integrated amplifier designs.  In addition,… Continue reading The Leben CS-600 ~ An Introduction to Leben Tube Amplifiers

Here is my first tube photo in a while: a Russian 5U3C (Cyrillic: 5Ц3C) rectifier tube from 1976. It’s what’s known as New Old Stock (NOS), meaning that the tube has never been used. The tube was bought for a Kondo Audio Note KSL-M7 preamplifier clone produced and sold by the Chinese brand Sunbuck on… Continue reading Sunbuck Kondo Audio Note KSL-M7 preamplifier “clone”/ Exploding Capacitors

Originally designed for use in televisions and radios, 6CS7 tubes are rarely used in audio products. The chief designer and owner of Leben Hi-Fi Stereo Company, Mr. Taku Hyodo, who is often referred to as one of the eight best tube amplifier designers in Japan, has a fondness for the 6CS7 type, presumably because of… Continue reading 6CS7 Tubes: Data, Specifications & Usage

In addition to a Leben tube amplifier, I’m also satisfied owner of Leben’s only RIAA so far, the Leben RS-30EQ, which both looks and sounds stunningly well. The RS-30EQ RIAA is based on a circuit including a single 6X5GT rectifier tube and two 12AT7s Jan Philips tubes. The European designation for the 12AT7 is ECC81. 6X5GT… Continue reading The Leben RS30-EQ RIAA, 6X5GT & ECC81 Tubes

When going through the photos in my blog post on my Leben amplifier, I noticed that the damper tube in this photo: was marked 6DN3, which I, funnily enough, hadn’t noticed before. I was of the impression that the CS-600 uses 6CJ3 tubes, which is stated on Leben’s official site. In the folder that came… Continue reading 6CJ3, 6DN3, 6CM3, 6CH3 and 6DW4B damper tubes