Condensed high-end audio design philosophy andaudio design know-hows learned from over 6 decades of our experiencein a small cabinet as small as an A4-sized footprint. The UD-505-X is a class-leading dual monaural USB DAC with an integrated fully-balanced headphone amplifier,that fuses high-end audio design concepts and TEAC’s decades of audio design experience, in an A4-sized footprint.The dual mono structure processes stereo signals with higher purity, and the D/A converter section usesone ESS Technology ES9038 Q2M in each of the left and right channels.This model achieves a high signal-to-noise ratio by using each DAC in mono mode.Moreover, we upgraded it with high specifications that enable native playback of22.5MHz DSD and 768kHz/32bit PCM formats. In the analog processing section,which can be considered the key to audio quality, we include four TEAC-HCLD2 circuits.These are improved versions of our previous TEAC-HCLD. For headphone output using the newly-adopteddiamond buffer circuit, in addition to two standard 6.3mm connectors, one 4.4mm 5-pole headphone connectoris available, enabling balanced connection and active ground connection with a single plug.The Bluetooth® receiver supporting LDAC™ and Qualcomm® aptX HD™ allows you to enjoyhigh-quality wireless audio streaming from your smartphone on this reference USB DAC.