Explanation: A diode detector is a simple, passive device that rectifies the incoming RF signal to extract the audio envelope. Its primary function is the necessary non-linear operation of rectification. Because it doesn't amplify the signal, it generally introduces very little additional distortion beyond this essential process, especially when properly loaded. In contrast, a triode detector is an active device that provides both detection and amplification. It relies on the non-linear characteristic curve of the vacuum tube for detection. While it offers gain, this reliance on the tube's operating curve, combined with the amplification process itself, often introduces more unwanted harmonics and intermodulation products into the audio output. This results in generally higher overall distortion compared to a well-designed diode detector, which primarily focuses on direct rectification without the complexities and potential non-linearities associated with active amplification.