Mixing Sub Size

[Alpine2005 10+ year member]

some of you guys says that mixing sub size is a bad idea because they will cancel each other out. but what do you guys mean with cancel each other?

would they only cancel each other out if their in the same box?

but what if their in separate boxs?

Click to read more...

 

[cjjackson85 5,000+ posts]

Would get cancellation either way...

 

[PhatTonyDeMarco 5,000+ posts]

He does not understand what the term "cancel out" refers to. (Neither do I.) So posting that would help...

 

[jsloan10 10+ year member]

Didn't a few of the Alpine demo cars have 10s,12s,and 15s, all in the same car?.

Cancellation occurs when two exactly opposite soundwaves run into each other.

 

[flakko 5,000+ posts]

ermmm one of the gurus should help out here or use the "search" its amazing what you can find.

 

[Loudrango112 10+ year member]

Your vechcal... car... truck...suv... whatever... has a "area" called the "cabin"

The cabin is where the sound will travel... if you have 2 different size subs... weither its in a seperate box.... seperate area... or whatever... they will cancle....

Do not do it... unless you want to waste time... money.... and effort....

The only way ive seen this done... was through different equalizers... and alot of PROFESSIONAL work.... and it does work.... but you need a nice setup to work...

Correct me if Im wrong...

 

[analogkid]

the only time mixing sub sizes is ok is when you have each size tuned to a specific freq range(ex: 1-15" from 0-50hz and 2-10" from 50-100hz). not that those would be the frequencies you'd use but if it is set up as mentioned the subs will not fight each other by cancellation. it also makes it harder for you because now you have to blend 2 diff kinds of sub bass to your existing setup. it will take more work to achieve the best sound possible.

dammit ya beat me.... //content.invisioncic.com/y282845/emoticons/furious.gif.fc81ca146dbff91fede3ed290dbc4f4c.gif

 

[cjjackson85 5,000+ posts]

Your vechcal... car... truck...suv... whatever... has a "area" called the "cabin"
The cabin is where the sound will travel... if you have 2 different size subs... weither its in a seperate box.... seperate area... or whatever... they will cancle....

Do not do it... unless you want to waste time... money.... and effort....

The only way ive seen this done... was through different equalizers... and alot of PROFESSIONAL work.... and it does work.... but you need a nice setup to work...

Correct me if Im wrong...

Learn to spell correctly you stupid man...

 

[Loudrango112 10+ year member]

Just imagine... non stop bass..... I know that sounds good...

But not when your trying to listen to music.... it just sounds mudded and nasty... and sick... and yuck

 

[Loudrango112 10+ year member]

Learn to spell correctly you stupid man...

I get in this "zone" and just go... and don't care to worry about spelling till afterwards.... then I just could careless to go back and fix it...

I save all of that for my english classes //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[T9X 10+ year member]

Squeak should chime in any time now.

 

[Alpine CDA-9815 10+ year member]

If you had them in separate boxes, with separate amps, and them playing different frequencies (15's- 50Hz below, 10's 51-100Hz, etc.) it should work. I have seen it done befor, but I didn't ask any questions. I could be wrong though. I wouldn't suggest trying it.

 

[cjjackson85 5,000+ posts]

If you had them in separate boxes, with separate amps, and them playing different frequencies (15's- 50Hz below, 10's 51-100Hz, etc.) it should work. I have seen it done befor, but I didn't ask any questions. I could be wrong though. I wouldn't suggest trying it.

Yeah you are, the crossovers aren't like brick walls, they are attenuaters. Some cancellation will still occur...

 

[jsloan10 10+ year member]

Heres a bit of an explaination on cancellation.

The soundwaves that come off the front of a speaker are the exact opposite of the sound waves that come off of the back of the cone, this is why we use enclosures to control the soundwaves coming off one side of a subwoofer cone.

These sound waves look like the wavy line on an ocillascope. As a speaker pushes out it makes a positive wave but the back of the cone makes a negative wave at the same time, if the positive wave and the negative wave collide they cancel each other out and there is nothing left to move our ear drum.

If you have ever played a sub without an enclosure you can see the result of this, the cone flaps about without making any bass.

In a multi speaker setup you can run into this problem when two seperate speakers are playing the same frequencys at different polaritys (a + wave collides with a - wave).

For a multi sub size set up it is reccomended that you dived the lower octaves for each sub.

like this for example-

Mid woofer- 100 to 200hz, 6.5' to 8' driver in a stereo pair

Woofer - 60 to 100hz, 8' to 10' driver mono

Subwoofer- 10 to 60hz, 12' to 18' driver mono

Hope that helps a bit.

 

[squeak9798 5,000+ posts]

Cancellation is covered nicely here:

http://www.betteraudio.com/geolemon/Phasing/Phasing.htm

Anyways....the main problem with mixing sub sizes isn't the cancellation issues (you can have cancellation anytime you have more than 1 speaker playing the same frequency).....but rather the necessity of it.

#1; Unless done "right" (which can work, by the way), the two simply won't sound good together. They'll have different frequency responses, different output levels, etc etc...which overall will result in a very poor, muddy, unfocused sound.

#2; With the quality of todays subwoofers; there really is no need for it. The "main" reason people do it is because they are working under the misconception that they need a 10" sub for the "punchy bass" and a 15 for the "low end".....all in one setup. Well, pretty much any quality subwoofer will be able to satisfactorily play the entire subbass bandwidth by itself, regardless of diameter....there is no need to break it up between drivers by frequency range.

Now, how can you make it work?? As someone mentioned; with careful tuning of the crossover so that they play different frequency ranges, using them in separate boxes and different alignments, etc etc.....But, IMHO this is pretty much a waste of resources, time, effort and real estate because, as I said, any quality subwoofer will play the entire subbass region just fine.