I wanted to hear the sound of a vacuum tube amplifier, so I purchased one from Otono Kobo. It has a powerful, beautiful sound. I am selling it to organize my equipment. Please check the following URL for details. https://otonokobo.jp/01_products/SK-100.html#feature ■ Amazing sound quality with a super triode connection circuit The SK-100 is a completed vacuum tube amplifier made and fully adjusted by Otono Kobo. Using carefully selected circuits and carefully selected parts, the powerful bass, clear mid-range, and extended treble are astonishing. Even though they are called vacuum tube amplifiers, the sound produced varies greatly depending on the circuit, construction, and parts used. The super triode connection circuit maximizes the characteristics of the vacuum tube, and it will not disappoint. ■ 3 inputs, can be switched with the front selector knob You can connect a CD player, tuner, record player (*), etc. Recently, the number of input devices that attract interest, such as network players and DACs, has increased. Having many input systems allows you to upgrade with peace of mind in the future. (*) In the case of a record player, it is necessary to connect it to the vacuum tube amplifier through a phono equalizer. ■ Equipped with a headphone jack, it can also be used as a vacuum tube headphone amplifier Don't you want to listen to the sound of a vacuum tube amplifier carefully with headphones? There is another world waiting there. Headphone amplifiers require complete silence with no noise. It is not easy to achieve this with vacuum tubes. The SK-100 achieves that silence and reproduces only the music signal, so you can feel the live sound right there. ■ This authentic vacuum tube amplifier is, of course, made in Japan It is a "Made in JAPAN" amplifier that I make with care and sincerity. While eliminating the concept that "vacuum tube amplifiers are expensive," we have achieved sound quality comparable to high-end models. "Otono Kobo" is able to offer a full-fledged amplifier that is particular about the parts and circuits used at this price. Please consult with me if the price negotiation is reasonable. Thank you.