A compressor is the right answer. If you lean toward more old-school audio engineering, I would recommend one of these compressors:

* Alesis 3630

* DBX 166 or 266

* FMR Audio Really Nice Compressor

Explore the various demos on YouTube to see what these are about. The compressor goes between your audio source and your amplifier. I personally use the Alesis 3630 for normalizing the audio in my ham radio transceiver setup.

Seconded on MiniDSP being a great solution.

You can have four different presets for different signal processing. The important part is that you can set them up how YOU want. Proprietary black box DSP parameters labeled as “night mode” or “movie mode” are hardly descriptive enough for my taste.

It is also worth mentioning that if you decide to get a Dirac model/license, it is locked to the device instead of the purchaser. This is big deal for resale value, as many receivers lock licenses to the purchaser (and aren’t readily transferrable to new gear).

I am a big fan of what they are doing in the space. I recently purchased a HTX from them for my living room and I have been as happy as a clam.