If you ever wanna help me/give me pointers on how to set up OBS so that my loud ass musical instruments sound nice while my voice is still audible, I'd be happy for the help
Ehhhhh for music, you want to be careful how much compression you use, because it will make music sound like shit. Compression with makeup gain is how music CDs got "ruined" 20 years or so ago, they used it to make everything as "loud" as possible, and in the process removed all the dynamic range from the recordings, which makes them sound bad.
However, compression is a GODSEND for voice. It makes quiet talkers louder, and loud talkers quieter, all automatically, in real time.
To accomplish voice compression, do the following (you can probably do a less aggressive version of this for your whistles):
Hit the cogwheel next to your audio source (mic, or audio output capture, or whatever), then click "filters." Click the + icon in the lower left to add a filter, and choose compressor.
Turn Ratio ALL THE WAY UP.
Turn Threshold, Attack, and Release ALL THE WAY DOWN.
Set sidechain/ducking to none.
Then, while making sound of a typical noise level, adjust "Output gain" up and down (probably upward to a degree), while watching the meters on OBS. You want the sound to peak at the lower end of the yellow part of the bars.
Once you have it set where you want, make a test recording, keeping an eye on that meter. The sound should always go to the lower end of the yellow, no matter how loud or quiet you are.
If you're in a noisy room, you might also want to add (and play around with) a noise suppression filter.
BUT FOR INSTRUMENTS:
You're going to want MUCH less aggressive settings. Go way easier on both the ratio and the output gain. You want to be able to have some dynamic range. You'll have to play around with it some to see what sounds best.
Here's a visual model of what compression does:
A 1:1 ratio is the same as not using a compressor at all... quiet things are quiet, loud things are loud. You set your threshold as the "pivot point" for when something starts not being as loud, and then tune the ratio to say "how much quieter should it be than it really is." The lower the threshold, the more the pivot point moves to the left, and the earlier the "quietening" starts to happen. Attack time is "how quick the filter kicks in when the threshold is met," which should always be as fast as possible, and "release time" is the delay on how long after the input sound goes below the threshold level that it turns off, which you also want to be as low as possible.
So, that's how you make loud things quiet. To make loud things quiet AND quiet things loud, you have to first, compress everything to stupid quiet (hence setting the threshold down to stupid low levels) and then "make up" the attenuation by applying output gain (sometimes actually called Make-Up Gain in other audio equipment). That flattens out the sound, keeping everything at the same level, no matter how loud or quiet it started out as. But Dynamic Range (what this method of compression removes) is a GOOD thing for music, and matters less for non-sung vocals. So you can still eliminate clipping using a compressor, but be much more gentle with it... set threshold MUCH higher, and your makeup gain MUCH lower. Toy with it, and make test recordings, until you get a good balance of "doesn't clip" but still "doesn't sound fuzzy."