two or one sub?

I am having this lil argument with my friend about if its better to get one or two subs. Why do you think people are getting two subs intead of getting one and getting same ammount of power out of it?

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Infinity 1242, Kenwood 7202, Panasonic dec

There is no definite answer to this. There are pros and cons to both.

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well as dwarren said there are goods and not so goods in having one or two subs. the reason that people seem to go with two is because there is a louder punch to the beat because you get +3db from having another sub there. BUT there is a problem. they will take up more space and will have a problem with cancellation that happens with that. it is were the waves the sub creates cross or run into each other canceling out each other. and with a single sub that doesn't happen. there is less space taken up and the is no cancellation that happens. but you have to have more power or a different more efficient box to equal the db of the pair of subs. but in the end it is all about what the person wants. hope this helps settle that

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Want to know some good equipment- JL,Adire Audio,Mcintosh,Brax,Helix,Eclipse,JBL,RE,Dimoand Audio,Zapco, pritty much anything DYhon,Forbidden recommend
On the12volt you give some info and you get in

One good sub setup is plenty for SQ, unless you have a reason to use more...like you're installing a huge powerful system, have a very large vehicle, or are using small subs.  Reasons like that.  If SQ is your goal, IMO you should build on the premise of using one 12" sub. 

On the other side of the fence, if SPL is more important to you, then work with multiple subs if you want.  Most people now like to say "I got subS".  Just keep in mind it will be more difficult to achieve a natural response of music frequencies with a lot of cone area and power dedicated to just the under-100 Hz range.

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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

Aaron,

it is possible to get a theoretical 3 dbs by adding another woofer, but there are variables that come into play- mainly the ohm load presented to the amplifier, and what ohm load the amp is stable into.  If you have two 4 ohm single voice coil subwoofers, you can either wire them in parallel- for a 2 ohm load, or in series- for an 8 ohm load.  Now if you have an amp that's stable to 4 ohm mono, you're better off with one sub from a db standpoint, because if you hook up two it'd have to be at 8 ohms, so you'd effectively have 3dbs less.

Also, space can be a concern, but cancellation is rarely an issue, unless the subs are poorly placed- one up front with one in the back (or something else ridiculous like that).  Usually woofers will be placed on the same plane, or at least the same general area, where they will complement each other.

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My ex once told me I have a perfect face for radio.

Another reason people are getting 2 subs is in advertisement.  Everyone pushes 2 subs.  It makes more profit for the seller (not saying all audio sellers do that).  2 also sounds better than 1 to some people.

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That's my opinion. Take it, leave it, or correct me.

i push alot more than 2 subs. in fact i dont think i have ever had less than 3

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84 Mazda Rx7 GS
4 15" Audiobahn High Excursion
1 2500W Orion Amp
Custom Box

audiobhan101 wrote:

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i push alot more than 2 subs. in fact i dont think i have ever had less than 3

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Im sorry....2 subs is plenty for me, I think If I had all 4 running at once besides at shows I would be in big big trouble

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2009 0-1000 Trunk WR 154.0DB 2009 1001+ Trunk WR
2007 USACI World Champion
2007 World Record
2006 USACI Finals 2nd Place

youngone wrote:

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the reason that people seem to go with two is because there is a louder punch to the beat because you get +3db from having another sub there.

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The general rule of the thumb for doubling cone area is +6dB, not 3dB. Doubling power provides +3dB.

geepherder wrote:

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cancellation is rarely an issue, unless the subs are poorly placed

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Indeed, a pair of woofers on the same plane, with summed inputs playing in a common enclosure will absolutely *not* produce 'cancelation.'

arrow12 wrote:

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2 also sounds better than 1 to some people.

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yea seriously pairs of woofers just have this certain spank that single woofers just don't provide. Having used a single 13w6 for a year, moving to a pair of 12's (even at HALF the power) was much, much more satisfying lemmie tell ya..

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"I'm finished!" - Daniel Plainview

I have had as many as 6 12s' in one vehicle over the years, my previous setup was two 15 inch audiobahn immortals...It all depends on what you want. But even for spl one really good woofer that handles lots of power is hard to beat for ease of wiring, box size and design. Basically just a lot less hassles. Right now I am running a single 15" Digital Designs woofer and on any given day it will spank any multiple woofer setup with close to the same power. I can honestly say I will personally never have another multi woofer setup unless I decide to go hardcore spl and need a system that will handle 10,000 watts or so. Also, I've never seen anyone gain 6db on the meter  just by adding another woofer with the same amount of power. In the real world, you would likely only gain about 2db.

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Gettin' deafer by the day.......96' GMC yukon-Eclipse CD 5442HU
MA Audio HK4000D-Digital Designs 9515F
150+db with one woofer...DD rules!!!!

sedate wrote:

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The general rule of the thumb for doubling cone area is +6dB, not 3dB.

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ddsubman wrote:

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I've never seen anyone gain 6db on the meter  just by adding another woofer with the same amount of power. In the real world, you would likely only gain about 2db.

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3 db is figured in a perfect world, and I would agree with the above that the real world usually shows about 2 db increase.  I'm guessing that sedate is assuming a doubling of power along with the doubling of cone area to arrive at +6 db.

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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

Huh ..

yea I mean generally adding a woofer involves halving the impedence of the system, so when ppl say "add a sub" I always assume they mean "another radiating diaphram identically configured to one I have" ...

Real world only 2dB? Huh. I halved the power going to my subs ... 480watts down from 800, but switched to a pair of CDT 12's from a 13w6 and I'm *much* more satisfied. Much, much louder at any frequency..

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"I'm finished!" - Daniel Plainview

sedate wrote:

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Huh ..

yea I mean generally adding a woofer involves halving the impedence of the system, so when ppl say "add a sub" I always assume they mean "another radiating diaphram identically configured to one I have" ...

Real world only 2dB? Huh. I halved the power going to my subs ... 480watts down from 800, but switched to a pair of CDT 12's from a 13w6 and I'm *much* more satisfied. Much, much louder at any frequency..

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What was that....techspeak doubletalk perhaps? Half of 800 is not 480, I think your calc needs some new batteries....LOL . But seriously though, 2 brand new speakers should sound better than 1 tired old JL.  sounds more like apples versus oranges to me. I was speaking from my experience as a competitor,    and as many variations as I have run over the years, of course 2 high end woofers will sound better than a Pyramid original. I just know that 1 Digital Designs 15inch woofer will turn better numbers on an spl meter than 2 audiobahn immortals running the same power. Been there done that.

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Gettin' deafer by the day.......96' GMC yukon-Eclipse CD 5442HU
MA Audio HK4000D-Digital Designs 9515F
150+db with one woofer...DD rules!!!!

How long have you had the 9515, and how do you like it overall? I finally powered up my 3510 with about 1500rms give or take, and I cant even imagine running much more on the street without serrious hearing loss. I think the problem is most people are under the impression that running 2+ is that much louder and in many cases sacrafice speaker quality, box design/size, and power thinking that 2+ will be that much better then one properly installed sub. Then again everyone to their own.

ddsubman wrote:

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alf of 800 is not 480, I think your calc needs some new batteries....LOL .

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Bad math eh? Lemmie rephrase:

I doubled the impedence on my amp and *almost* halved the power output...

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"I'm finished!" - Daniel Plainview

I've had my 9515 for about 3 years. It was originally a "d" series, one of the voice coils dropped out so I sent it back to DD for a rebuild. They upgraded eveything to the new "f" series and I put it back in my yukon about 3 weeks ago. I am really impressed with the power handling and sound quality, even though they are built mainly for spl purposes. One thing a lot of people don't realize about DD woofers either is that once you buy one from them, you never have to buy another! After the factory warranty runs out you can ship your woofer back to them yourself if something happens. I'm not sure about the lower series woofers, but for $130 they completely rebuilt my woofer. The only original part that wasn't replaced was the motor. They even attached the newer style basket. I continuosly  run mine at about 2,000 watts for ride around and almost 4,000 for competitions. I have however, seen the same style woofer "burped" at the competitons with close to 10,000 watts and emerge unscathed! I'm saving up my money to buy another ma amp and a 9917 to compete with and put the 95 series woofer in my wife's car.

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Gettin' deafer by the day.......96' GMC yukon-Eclipse CD 5442HU
MA Audio HK4000D-Digital Designs 9515F
150+db with one woofer...DD rules!!!!