Не совсем понятно, что нужно опознать? Микросхему? Думаю что-то из УНЧ, или какой то элемент между микрофоном и микросхемой? Если элемент, то кроме керамических конденсаторов и резисторов ничего заумного там не увидел.
Даташит может быть и не найти. DESCRIPTION The FR6391 is a CMOS IC that has a microphone peripheral circuit and an echo generation circuit for karaoke use, on a single chip.
FEATURES • High-performance digital echo circuit using 44-Kbit RAM • A mic amplifier with an ALC makes it possible to handle overload input, and the ALC operating voltage can be externally set to the desired value. • Built-in mic volume, echo volume, and feedback volume • Internal micmixing amplifier • The clock has an internal current control-type oscillation circuit, and the generation of unnecessary oscillation can be prevented because the clock does not affect anything external to the unit. • Internal Auto Reset circuit that functions when the power supply is turned on. • MIC Volume, Echo Volume, and Feedback Volume are controlled by I2C Bus or DC control. • 5V single power supply
APPLICATIONS • Wireless Microphone • Karaoke System • Consumer Audio Applications • Car Entertainment System