How to make music sound like mastered FM Radio?

I want my songs to sound like a mastered FM Radio. However, I do not know how to make that, so any help would be great.
Audacity version: 3.0.2

How does the radio sound different from a CD or MP3 to you?

FM is supposed to be high-fidelity, which means ideally it should sound exactly like the the CD or digital file they are playing. AM radio is not high fidelity. It looses the high frequencies and it’s more subject to noise pick-up. With FM you do get some hiss (especially with distant stations) and radio stations often use dynamic compression to make everything “louder” and to make everything the same volume (so you don’t alternate between quiet songs and loud songs). This also removes some of the musical dynamic contrast which means the quieter parts of the song boosted to match the louder parts. (IMO - A lot of modern music is already “over compressed” and constant-loudness-boring!)

If you want to try compression, try the limiter effect first before playing with the compressor effect. Limiting is a kind-of fast compression and there are fewer settings to mess with.

You may want to run the Amplify effect (and accept the default to “maximize” the volume) before the limiter or compressor. That gives you a starting point. For example, if your peaks are -3dB and you set the limiter to -3dB, nothing will happen. If you amplify your peaks to 0dB, the limiter will do it’s thing and reduce the peaks by 3dB.

Since compression and limiting tend to “push down” the louder parts, it’s common to use “make-up gain” to boost the overall volume. That’s up to you…

BTW - Radio stations are REQUIRED to have a limiter on the transmitter because it’s illegal to over-modulate. But, they are NOT required to run a hot signal that constantly uses the limiter. They can set their levels so the limiter only kicks-in with “mistakes”.

Multi-band compression is better than single band.
There are free multiband compression plugins which work in Audacity on Windows
e.g. KHSMR* , GMulti.

[ * “pressure” knob is mutiband, “comp” is single band ]

Could you provide me some screenshots please? Like how to set the limiter, amplify, compressor…

There is a free plugin called Devicer by Plectronfx which works in the 32-bit version of Audacity,
It has several radio / home-stereo effects.
But as it’s an old 32-bit plugin it won’t work in the 64-bit version of Audacity.

I have Windows 10 64x, so I guess it will not work for me.

You can perfectly install 32-bit applications, including the 32-bit version of Audacity, in a 64-bit version of Windows 10.

In a slightly different direction, this plugin.

That will perform the same functions as FM Radio Transmitter limiters. As in that post, music and comedy programs sound exactly like the local FM station, minus the stereo intercarrier hiss. Just add a bit of pink noise to the background and you got it.

I discovered this process when I went from off-air KPCC to internet download of “Car Talk,” among others. The sound quality skyrockted and the transmitter fffffffff vanished, but I was presented with the raw studio sound. One of the presenters mumbled in his beer and the other had a thermonuclear laugh. Can’t listen in the car, pretty much the problem that Chris had.

Problem solved. Pay attention to that end-of-show bug.

I don’t put the hiss back.