1. Op amp with better effect OPA1611 OPA16122. USB uses XMOS208 imported chip3. Bluetooth module uses Qualcomm QCC3008, support for APTXBasic parameters:Voltage: DC 9V (with 100V-240VAC to 9VDC adapter)Size: length 103x width 150 x height 40MMInput support:Coaxial: PCM44.1k~192k 24bit/DOP DSD64Optical fiber: PCM44.1k~192k 24bit/DOP DSD64USB: PCM44.1k~384k 32bit/DSD64, DSD128, DSD256Colour:silverMaterial:Aluminum alloyPackage Contents:1 x DAC DecoderOnly the above package content, other products are not included.Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.