Russian Bayan Accordion
The Bayan is a chormatic button accordion developed in Russia in the early 20th century. It was named after the 11th-century bard Boyan. This instrument is different from regular keyboard accordions. Instead of a keyboard this instrument has a serious of chromatic buttons. The reeds in this instrument are broader and rectangular vs trapezoidal. This helps produce the fuller sound of the bass. The tone of the Bayan is best described as a miniature church organ. This instrument is usually only played by accordion virtuosi who want to perform classical music such as Bach.
For example here is a video of someone playing one of Bach's Toccata and Fugues on this instrument. Enjoy And below another student ripping on one of these fabulous instruments.