I'm selling this because I've never used it after purchasing it! Here's the description: -◎- Perfect for those who want to balance multiple instruments and volumes with a single amplifier, or play along with CDs... Simply put, it's great to have! -◎- It seems to be an essential item for professional musicians and live venues... -◎- A passive mixer with 4 inputs and 1 output! STEREO specifications are also available! -◎- By using components such as Western Electric and Kester, it can faithfully reproduce the original sound. ＜＜CIRCUIT＞＞ IN 1 (Volume) + IN 2 (Volume) + IN 3 (Volume) + IN 4 (Volume) ⇒ OUT ◆ 4in1-T ◆ A standard type with 4 inputs and 1 output. ★ ATTENTION ★ ＜Please note the following points as it is a passive circuit＞ It is an attenuation type (volume full is 1:1) *It does not increase gain. The volume may be attenuated from the original sound (the attenuation rate varies depending on the connected equipment, etc.). As it is a summing mixer, there is no change in tone, such as EQ.