Optimization

Instead of punching islands or using commercial pads (islands) or making traditional pads myself, I simply make use of small pieces of single-sided PCBs to create the pads / islands easily for my boards. This technique has a huge advantage over the punched islands or scored and divided boards techniques as it keeps the bottom ground plane perfectly 100% intact! Also, it is almost a tool-free process to create the pads by breaking or cutting the single-sided PCBs. Single-sided prototyping boards also happen to be very reasonably priced. ...

Tangara is a pretty awesome project! It recently inspired us to build a similar FOSS DAP product but at a much lower cost of <= 40 USD. Our initial tech stack: RP2350-Zero, PCM5102A 32-bit 384kHz DAC, Burr-Brown OPA1662 (specified for 3.3v) as the unity gain buffer and headphone driver, no explicit DC-DC converters anywhere, microSD card, everything will be a module if possible We quickly got this prototype working on a breadboard and discovered some limitations: ...

Tangara is a pretty awesome project - no doubts about it. I found this review of Tangara's design pretty interesting and educational. It has inspired us to build a similar FOSS DAP product but at a much lower cost of 40 USD (that being the launch price of Sansa Clip in year 2007). The idea is to deliver '90% of the value' of Tangara in a slightly smaller (but fatter) and more cost-effective package. ...