Gōng / chéng / shī / gēng / huàn / le / shù / mó / zhuǎn / huàn / qì / yǐ / gǎi / shàn / shè / bèi / de / yīn / zhì工程师更换了数模转换器,以改善设备的音质。The engineer replaced the digital-to-analog converter to improve the device's sound quality.