Compander

[WSHH887]

So if I understand correctly, compander is used to reduce noise on weak signals. Why would you not want compander programmed on all of your radios channels?

[Radioguy7268]

Compander = Compression/Expander 

It's a method to re-constitute your voice after the insignificant audio has been squeezed out of it. Just like concentrated Orange Juice doesn't taste the same as fresh squeezed - Compandered audio isn't the same as the Original audio.

For 12.5 narrowband, it was considered a win in the overall audio picture, but you gave up some tonal quality while it did reduce background noise and hiss. In 25 kHz wideband, I never really saw the benefit to using it.

It's also a system wide setting, so if only one radio on your channel is using it, all the other units will not hear him clearly & vice/versa. Better to have everyone using the Compander feature, and not all radios offer the feature - and not all radios treat the compandered audio exactly the same during compression/expansion. It can lead to odd sounding audio.  I've also seen some radios display a lack of sensitivity at the edge of coverage when using compandered audio. 

I played around with that a bit in the late 90's with the onset of narrowbanding.  the TLDR was: use if it it works, but you're better off to implement it from the start. Migrating a user group over to it was a PITA - especially if they had a mix of radio models.

[SteveShannon]

Using compander adds some audio elements that are not always pleasant. There’s almost always some background hiss in audio. That hiss is compressed along with the desired audio at the transmitter and expanded at the receiver. Some refer to the sound as resembling loud breathing or pumping. I started with compander turned on but didn’t like the sound. I have turned it off now. 

[WRHS218]

58 minutes ago, SteveShannon said:

Some refer to the sound as resembling loud breathing or pumping.

This is not how we radio in a polite society.

[WRUE951]

short for "compressing and expanding," is a technique used in ham and commercial radio to mitigate the effects of a communication channel with limited dynamic range. It compresses the dynamic range of an audio signal at the transmitter and then expands it back to its original range at the receiver. It is suppose to help improve the signal-to-noise ratio, making the audio clearer when in environments with background noise or over long distances. However, the process can introduce distortion, mostly in analog radios, where the output may not perfectly match the original input as Steve Shannon suggested.  

[WSHH887]

Thanks. I'm still learning. I think I'll avoid compander unless issues arise. And in that case it may or may not do any good.