You've got a good attitude to start off with. As I am wont to do, I'm including a link to your owner's manual. It's rudimentary but doesn't seem lacking.
https://acousticamplification.com/wp-content/uploads/2014/11/usermanual/B200H-Manual.pdf
Page 7 is where things start to get interesting: a description of your front panel. In high-level terms, you have 3 functions of interest
- Preamplifier
- Tone shaping
- Output amplifier
The preamp is all about getting the best signal into your amplifier. Starting from the left, you've got two input sockets, one for Active basses and one for passive basses. Plug your bass into the appropriate input. Next you have the Gain adjustment knob. This boosts the level coming from your bass. The clip light indicates when the signal level is too strong and might lead to a distorted sound. I'm going to assume you don't want distortion so you want to play your bass hard, reach the Gain point where the clip light starts to light, then back off a bit. This should give you the hottest signal without distortion.
I'm going to skip the Volume knob for now, as it's not in my sequence.
This amp has a rather complex tone shaping circuit, more so that the usual bass/mid/treble. What you have is a 6-band Equalizer with an additional notch filter. Cool, huh? An equalizer is an audio tool that allows you to either cut or boost certain frequencies. Here's how to learn it: an assistant knob-twiddler is always welcome.
- Set all of the equalizer knobs to 12 o'clock. You might feel an indent here, a natural settling spot.
- Play your bass and turn the 63 Hz knob to the left. You should hear the lowest deepest frequencies thin out a bit, as you've cut out their strength.
- Keep playing your bass and turn the 63 Hz knob to the right. You should hear the lowest deepest frequencies become very enhanced, as you've boosted their strength. Return the knob to 12 o'clock.
- Continue in this manner with each of the equalizer knobs. As you progress from left to right, you will be cutting or boosting higher frequencies.
So the equalizer is used to obtain an overall tone to your liking. You may need to adjust it for different instruments, music styles, or for different locations, as space does affect our perception of tone. A room may be too "boom-y": cut the low frequencies. You want sizzle for your slap: boost some of the higher frequencies. Page 11 starts a section on recommended settings for various styles. Experiment.
Sometimes there are specific frequencies that need to be tamed. The Notch filter knob helps you zero in on such artifacts and lower their amplitude. This is totally subjective to the immediate environment and the only way to know if it's "right" is if it sounds better.
Back to the volume knob. This sets the overall output level of the sound you've crafted with your preamp and tone shaping.
Page 9 is the next point of interest: a description of the rear panel.
As you have a combo you have one 15" 8 ohms speaker connected to the amplifier internally. You have a Speaker Out socket that will allow you to connect an external 8 ohms speaker of your choice, creating a 4 ohms load, the minimum that this amp will be happy with. Do not connect a 4 ohms speaker as you will risk damaging the amp.
You have an Effects Loop, with a Send and Return. These are line-level connections to outboard effects processors, but not pedals. Pedals should be used between your bass and the combo's input, as they are all instrument-level.
Last, you have a Direct Output XLR connector. This is handy if you want to send your signal to a mixer, PA or audio recording interface. It has a level control so you can adjust the strength of the signal sent. There is also a ground lift button in cases where there is lots of noise on this line.
So I hope that helps.
