Gain staging:
The ideal gain staging is:
obs volume at +-0db
bridgecaster master volume set at +-0db,
mic channel volume at +-0db
mic gain set so things don't clip when loud.
When making adjustments start from the source and work your way up the stages to get things blanced properly.
if your overal balnce on the bridgecaster is good, but your still clipping obs input, drop the output of the bridgecaster.
Causes of distortion:
Clipping on inputs or outputs of hardware or software.
Limiters with fast release with audio way above threshold
Compressors with fast release with audio way above threshold
De-essers with audio way above threshold
Gate with super fast release and attack.
Tips when mixing audio:
Speech intelligibility: The fundamental tone of female voices is typically 200Hz - 220Hz. The fundamental tone of male voices is 100Hz - 120Hz. The most important freq range for inteligibility in english is 2kHz. A more in-depth article here.
Start with too much: Its faster to make adjustments by going past what sounds good and then dialing it back into acceptable range. The human brain responds better to higher contrast, so instead of gradually and incrementingly making changes and trying to decide if your changes are effective, it becomes much more obvious when you make bigger changes and then correct to acceptable values.
Beware ear fatigue: Listening to the same sound over and over again ruins your perspective on how something sounds. Always have another bit of audio to compare too. Example: Record some audio, listen back, listen to another bit of audio that's comparable (not in volume but in timbre), listen to yours, make adjustments, repeat until happy.
High-pass filter (hp) / low cut filter: Mics pick up everything that makes noise. The truck that rolled past your house, the subs your neighboors are blasting, the electrical hum your wires pick up, the sound of air hitting the mic, and so much more, your mic picks up all of it. Using a high-pass / low-cut filter to cut out the freq you aren't using ensures that that feq space is available for other things (explosions ffrom games, lowend from music, etc). Its a best practice to cut below the fundemental of your voice so that toggling the hp filter on & off makes no noticible difference to your voice.
Mic position: All microphones have different frequency responses based on your distance to the microphone. The most prominent effect of this is how much bass freq your voice has when you get closer to the mic vs far away. The only thing that really matters here is consistency. By maintaing a consistent distance from the mic you can guarantee a consistent sound.
Gain: Once you have your mic at a comfortable distance adjust the gain of the bridge caster till your peaks are in the yellow.
Sm7b Frequency Response: This is the frequency response for the sm7b. You can see from the chart the highend drops around 10Khz. This makes the mic naturally dull, so you need to brighten it up by boosting high freq's.
Glossary:
Frequency response: the timbre or sound of an audio device.
Proximity Effect: The increase in bass frequencies when physically closer to the microphone diaphragm.