Finished Dual AD1865R NOS DAC Hifi Audio Decoder with Balanced output | eBay
GIESELER AUDIO R2R NOS DAC | Gieseler Audio
Ladder DAC Board R2R NOS Balanced 24bit 384kHz - Audiophonics
Archimago's Musings: NOS vs. Digital Filtering DACs: Exploring filtering turned off, implications, fidelity and subjective audibility. (Recent BorderPatrol DAC chatter...)
AD1865 R-2R DAC Pi Hat - Audiophile Diyer
Audio-GD | Underwood HiFi
DIY NOS AD1865 DAC for Raspberry Pi - Audiophile Diyer