Ideal Volume

[Westeford]

So I'm finally adding music and sound effects to my project. But it got me thinking about the audio balancing. Some of the songs are inconsistent in their volume.
I guess what I'm asking is what do you do when testing audio. What's the ideal volume for music and sound effects and the ideal volume for testing?
And I'm not talking about the in-game volume, it's the volume of everything before putting it in the project.

My worry is that after I finish everything, the sound balancing that sounded fine to me. is either too loud or too quiet for everyone else.
Ideally I want the player to do only have to adjust the main volume at most and not have to touch the in game audio settings.

I hope I made sense. Thank you for your time.

[Imperf3kt]

I'd run all the audio through a volume normaliser in say, Audacity.
You'll lose a small amount of imperceptible quality and maximum noise floor, but you'll avoid the whole music drowns out sfx issue or the "this gunshot is so loud but if i turn down sfx, I cannot hear any other sfx" issue

[MarkusLappalainen]

What Imperf3kt said is an easy solution. It has its down sides though. If you normalise everything with the same setting, pieces that are supposed to be soft, now sound very loud next to tracks that are more loud of themselves. For example a soft and heart aching track sounds as loud as a big bad action track.

Normalisation is a process where you set a ceiling for volume and all signals are boosted until the highest peak hits the ceiling.

An alternative solution, which requires more work is running all tracks though a DAW (a music program in layman's terms) and adjusting the volume of each individual track in relationship to each other. Basically laying all pieces on one track and making loud ones softer and quiet ones louder. Takes more effort, but I feel the end result might be a tad more coherent and pleasing.