Why AM receivers leak audio quality?

[nayaki3004]

AM

why AM receivers leak audio quality

 

[DarkJedi]

Re: AM

Because AM modulated signals are more affected by noise than FM or PM modulated signals.

This is because in AM modulation the information travels in the amplitud of the signal, adding noise (Which is basically altering the amplitud) destroys the information of the signal, degrading the audio quality.

 

[biff44]

Re: AM

1) because it is analog AM, it picks up lots of stray noise (electrical motors, power lines, lightning)
2) to minimize this stray noise, there are lowpass filters in the receiver and transmitter to limit the audio bandwidth.
3) to cram as many stations into a limited AM broadcast band, the FCC has limited the radiating bandwidth that a broadcast AM transmitter can use. This also limits the audio bandwidth possible, and eliminates the possiblity of a multiplexed stereo channel.

 

[toonafishy]

Re: AM

There is no inherent reason why AM has poor quality. If the transmit and receive bandwidth are wide and the transmission channel is quiet, then the quality can be just as god as FM. However, in practice, the bandwidth is limited to fit more channels in the band. This compromise was made years ago when the quality of the audio wasn't that good anyway. The added sensitivity to band noise just makes things worse.