The Hidizs S9 Pro Plus, named 'Martha' in tribute to the last surviving female Passenger Pigeon, is a high-performance portable DAC/Amp designed for audiophiles. It features the ES9038Q2M DAC chip with ESS's patented HyperStream II architecture, supporting PCM up to 32-bit/768kHz and native DSD up to 512. The device includes physical buttons for volume control and six selectable filter options, allowing users to tailor their listening experience. It offers both 4.4mm balanced and 3.5mm single-ended outputs, ensuring compatibility with a wide range of headphones. The S9 Pro Plus has a robust and elegant design made from aerospace-grade aluminum, weighing just 17 grams. Additionally, it features RGB lighting to indicate sampling rates, enhancing the visual aspect of audio playback. Supported across multiple platforms, it ensures broad compatibility with devices like Windows, Mac OS, Android, and iOS. With a powerful output of 138mW for the 3.5mm output and 180mW for the 4.4mm output at 32Ω, it is capable of driving a variety of headphones, including high-impedance models. It also boasts low total harmonic distortion and an impressive signal-to-noise ratio, making it an excellent choice for those seeking exceptional audio quality on the go.