AIRBOW - Beat Stone Soul (Beat Stone Soul) (1 piece) (Sound Quality Improvement Mineral Accessory) Part 2 ※ Everything in the photos is included. The original comes with minerals, but this does not. Please understand this before bidding. This is a used item. Only the main unit is for sale. No pets, non-smoking environment. We would appreciate it if those who understand used items would purchase this. The sound of electrically amplified "inorganic" audio equipment gains "warmth" as if it has a "soul," transforming into a "organic" sound like live music. The thickness of the mid-range increases, and the dynamism of the music and the expansion of the sound are dramatically enhanced. The polished natural minerals come in color variations from "transparent" to "purple," and the effect changes slightly depending on the color, so we have prepared "paired items" that have been matched for sound quality through listening tests for stereo speakers. However, the sound quality does not change significantly even if the color of the mineral is different, so you don't have to be too concerned about the color matching of the mineral. Please place it on top of audio equipment, inside the speaker bass reflex port (be careful not to let it fall into the speaker), or on top of the speaker, etc.