Box setup and db/hz questions

[Baningu Yozora]

Hi, I'm brand new to car audio forms, and am a recent entry to car audio.

I wanted to upgrade from my single 10" @400w peak with a 300w amp (Don't remember RMS) so I bought two 12" 600w, and a 1,250w 2 channel amp. I want to be able to really feel the bass, but also get good lows. I'm thinking of building a hybrid box of bandpass and something else, but don't know what type of box for the vibrations.

Also, I can of corse switch the positions of different things. I don't know if the 10" at 300w is enough for a bandpass box, if I need to upgrade my amp to the full 400w, or if it's generally not enough however I could put the 12"s in a bandpass instead or buy a new 400w amp for the 10".

Also, is it the lows (DB Level), or how loud (Hz) that makes the vibrations/flex?

Thanks for your time, and I appreciate any input.

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[cfox10 10+ year member]

Which subs did you buy?

Why did you buy a 2 channel amp? What amp?

DB is the measurement used to tell how loud a sound is, Hz is a measurement of any given frequency.

How much vibration you get is dependent on both, typically the very low bass will move more air and produce 'flex' and the higher notes you will tend to feel more in the chest/head.

 

[Papermaker85 5,000+ posts]

lets guess how old he is..

i say 15.. or 18 and doesn't speak English well..

 

[Baningu Yozora]

I'm guessing you are talking about me. I'm 17, but what's it matter? It seems like you you are trying to spite me, but trust me it won't work. My subs are all different brands because I bought them cheap seperately. The brands don't matter though, rms peak and ohms are all the sake and compatible for the amp. 8 just need I'm put on the box and arrangement. I have a separate amp for the 10", but it doesen't matter for the question

 

[hispls 5,000+ posts]

My subs are all different brands because I bought them cheap seperately. The brands don't matter though

You have much to learn, young grasshopper

 

[CSCStang]

Mixing sub sizes and brands does matter if you're looking to get.....vibrations/flex? Cancellation is what you get.......

 

[ciaonzo 5,000+ posts]

I'm guessing you are talking about me. I'm 17, but what's it matter? It seems like you you are trying to spite me, but trust me it won't work. My subs are all different brands because I bought them cheap seperately. The brands don't matter though, rms peak and ohms are all the sake and compatible for the amp. 8 just need I'm put on the box and arrangement. I have a separate amp for the 10", but it doesen't matter for the question

Different drivers have different impedance profiles even if they have the same nominal impedance at rest. This means a couple of things to you.
One, the drivers will behave differently as power is applied to them due to the differences between capacitance and inductance phase angles found on either side of the resonance peak for the respective drivers. Even if the Fs is exactly the same among all the drivers (unlikely), the Q might not be. This means some drivers will be moving more than others at various frequencies (and this effect will alternate as you go up and down through the octaves), which will be causing phase issues as was already mentioned.

Two, the amplifier will be struggling with these very different impedance profiles among the different drivers and will be working much harder than you would expect. Not to mention the enclosure issues you will run into. The power thing could average out and end up being the exact opposite, but that's unlikely.

At a minimum, you will want all of your drivers to be exactly the same.

 

[Baningu Yozora]

Thanks for explaining this to me. I'm still going to do it because MDF doesen't cost too much to build boxes, and the subs were cheap. I still want to know what type of arrangement would be good to put them in though, because I could swap the subs out... 2 12"s aren't hard to find, and to gain experience like this it's money decently spent. Although if it works, I'd be happy!

On a side note I experienced getting enzyme carpet cleaner in my eye a few minuets ago... It hurt, and washing your eyes isn't fun, that's a bad experience.

 

[Baningu Yozora]

Can you please explain cancellation to me? I've only built one other sub box, and I know ohms, wiring, box size, air volume ect... But I don't know the details of subwoofers and sound.

 

[timhof13 10+ year member]

It's a waste of time to explain cancellation if your going ahead with this build. Do what the guys have said and STOP right now. If you have money to waste on mdf send it to me, I'm building a underseat box right now

 

[Jeffdachef 5,000+ posts]

Can you please explain cancellation to me? I've only built one other sub box, and I know ohms, wiring, box size, air volume ect... But I don't know the details of subwoofers and sound.

To make it extremely simple... cancellation = less bass than you would get with a single sub. Cancellation = canceled out or negative bass capisce?

Cheap in cheap out. Sell one sub and get an identical sub or sell both subs and get one good sub and hit up CSCstang for a proper T-line enclosure design and you'll get slamming hard. If you are willing to learn and accept advice, you'll be on the right track to flexing windshields young one.

 

[ciaonzo 5,000+ posts]

I guess if you're going to insist on using the different drivers together just to gain experience, I would be sure to put each driver in a seperate enclosure.

 

[big scott]

ya dont do it.... you will have less bass like the guys have said...

i tryed useing a crap kicker in its own box (it was ported but i sealed it ) i used this for my midbass as i just had gotten a soundqbed hdc3 15" sub.

was using the crappy kickers as a sub before my hdc3 .

well anyway , even playing higher notes throw the kickers i had less overall bass in my truck...

i pulled the kicker out and wow what a difference.

so what does all that mean.......

dont use different subs...........................................

 

[wew lad 5,000+ posts]

i.e. your bass will sound like shit

dont even think about questioning the advice given to you, we understand the way electricity, harmonic waves, and other physics can influence the outcome. you may think a little cancellation is no big deal, we know better.

 

[ciaonzo 5,000+ posts]

i.e. your bass will sound like shit

Nice, that's a perfect graphic representation.