Rep Power: 0

I'm new with knowing things about imports, I've always owned something domestic and I have rather good knowledge on what all car parts are and their functions but I got curious about the air system on my 2004 Civic because of the two boxes and the one that holds the air filter is self explanatory and I'm good with that one but the empty box before that, What in the world is it for?
I tried googling it but I only get links for aftermarket upgrades so I'm done with Google. I had my mechanic suggest that on some imports it could act as a noise maker to make these vehicles sound like they are a performance vehicle but other than that people say it's just part of the air system, leave it alone.
I just want a nice description of what it is, what does it do and how can it benefit the car?
If it's just a noise maker, can I remove it and just add a flex tube because I can't stand the sound, it sounds ridiculous when my car is completely stock and I don't plan on modifying it. I'm happy with it being stock because it's in excellent condition and that's what I need. So please explain the empty box. Thank you!

 
Rep Power: 222

It's supposed to be a silencer, car will have a louder intake noise without it. The cars are pretty quiet stock, maybe there's something else going on?

 
Rep Power: 243

Yeah it’s not a performance car so it doesn’t add noise but makes it more quiet. Civics aren’t exactly “quiet” and they can be a bit buzzy on the highway (the older ones).

 
Rep Power: 224

Silencer but I also believe it partially functions as a air/water separator. What kind of noises are you hearing?

 
Rep Power: 0

Pretty straight forward and understanding. I think it's just me, I'm not used to what an import sounds like. But thank you, I really didn't get what that extra box was but I understand you.

 
Rep Power: 0

I couldn't have described it better, that's what I hear. It's definitely quite other than when I speed up and get that sound. I'll just turn up the radio haha

 
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^ Like GolNat mentioned above in their message, it's kinda buzzy. Nothing is wrong with the car, I just think I'm not used to the sound of a stock import 4cyl with its tiny muffler and the air system. I'm not a huge fan of imports and especially the sounds of the ones that have been modified, I can't stand it, it's noise to me. I've been driving old modified muscle cars for so much of my life, it's just something I have to get used to. This little civic really is great and extremely reliable and that is what I was looking for.

 
Rep Power: 222

Maybe there's an exhaust leak? The manifold can crack, flanges can rot out

 
Rep Power: 367

small engine = higher gear ratios to keep speed, higher RPM for same speed. but do check for faulty parts

 
Rep Power: 0

I'll check things again but so far all those are still good.

 
Rep Power: 0

You're right, I forgot to think about that. For now all parts are good.

 
Rep Power: 367

note that small engines are easier to get higher combustion efficiency, so even if higher RPM, they don't consume as much and produce more HP/liter
older V6 250cc bikes were HP monsters but no torque
s2k were also HP monsters per liter back in the day, but no torque in low RPM