SPL Difference in 1 15 vs 2 12s

[DJSlowfets]

Before I get berated on "theres so many variables only god knows" im talking rule of thumb and am just trying to establish base knowledge If I had a sigle 15 in the same car same power tuned to 32 hz yea the displacement will obviously be different than a dual 12 setup...however if set equal how many dbs would I be losing in a single 15 setup with 1k vs 2 12s on 1k?

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[hispls 5,000+ posts]

All things being equal there should be little to no difference.

 

[kr15 5,000+ posts]

Its like 226sq inches on the 12s and something like 172 on a 15. All things being equal, the 12s should be about .8db louder

 

[Boomin_tahoe 5,000+ posts]

Depends on enclosure too. Power, as you stated, 1k.

In the past, 2 12's was the equivalant to a single 15.

 

[Papermaker85 5,000+ posts]

Generally 2 12s are louder. Less power compression for tge same if not better efficency.

 

[BOOMINGRANDPA 5,000+ posts]

yeah u loose in cone area but it really depends on box.. also what subs u thinking about?

 

[SubbinNCali 10+ year member]

x2. I've done it a number of times using the same power on each setup.

 

[DJSlowfets]

yeah u loose in cone area but it really depends on box.. also what subs u thinking about?

American Bass XR-15D2 down to 1 ohm on a lil rockford 1200.1 mono...should beat enough for a $550 system..unless someone round here is selling a 15 that can take 1k daily or an amp that can put out 1k?

 

[hispls 5,000+ posts]

Its like 226sq inches on the 12s and something like 172 on a 15. All things being equal, the 12s should be about .8db louder

I don't think you understand logarithmic scale.

 

[kr15 5,000+ posts]

I fully understand the difference between a linear function and a log function.

But in the event that im misunderstanding it in this case; enlighten me

 

[TRaGiK 10+ year member]

So here's my experience as of today on this exact topic.

I own a termlab with the clamp so I can check wattage.

Equipment is 2 DC Audio 2.0k amps, strapped at a half ohm per amp in the trunk of a 2003 Civic. Box dimensions are identical. The only differences in the boxes are single 15 was left side port, and the 2 12's have a center port. Both use a single, external, aero port.

Sub is/was DC Audio XL 15, and 2 DC XL 12's.

I tested as follows:

Car sealed, meter on the glass, keeping power under 2500 watts

Car sealed, meter on the glass, unlimited power

Drivers window down, meter in the kick, unlimited power

On 2300 watts, car sealed, 2 12's got me a .8db gain.

On 3500 watts, car sealed, I gained .7db.

Outlaw, I only gained .3db, BUT I ran out of time and wasn't able to do as much testing as I wanted/needed. I'm confident I'll get another .4 or so out of it. More testing with that later.

To the ear, there is ZERO difference. However, the car is more windy with the 2 12's. May just be port location, but the difference in felt wind is significant. Feels louder. Does NOT sound louder. IS louder on the meter.

If you're chasing numbers, in my experience, 2 12's are better with everything else being equal. I AM chasing numbers, so it's worth it.

If this is just a daily setup that you're not competing with, it won't make a bit of difference.

 

[BOOMINGRANDPA 5,000+ posts]

American Bass XR-15D2 down to 1 ohm on a lil rockford 1200.1 mono...should beat enough for a $550 system..unless someone round here is selling a 15 that can take 1k daily or an amp that can put out 1k?

guy had a fu 750 wanted $70 shipped for it.. if u interested i'll try, oh wait i got it, think it was something like kcr357 had it

 

[wew lad 5,000+ posts]

So here's my experience as of today on this exact topic.
I own a termlab with the clamp so I can check wattage.

Equipment is 2 DC Audio 2.0k amps, strapped at a half ohm per amp in the trunk of a 2003 Civic. Box dimensions are identical. The only differences in the boxes are single 15 was left side port, and the 2 12's have a center port. Both use a single, external, aero port.

Sub is/was DC Audio XL 15, and 2 DC XL 12's.

I tested as follows:

Car sealed, meter on the glass, keeping power under 2500 watts

Car sealed, meter on the glass, unlimited power

Drivers window down, meter in the kick, unlimited power

On 2300 watts, car sealed, 2 12's got me a .8db gain.

On 3500 watts, car sealed, I gained .7db.

Outlaw, I only gained .3db, BUT I ran out of time and wasn't able to do as much testing as I wanted/needed. I'm confident I'll get another .4 or so out of it. More testing with that later.

To the ear, there is ZERO difference. However, the car is more windy with the 2 12's. May just be port location, but the difference in felt wind is significant. Feels louder. Does NOT sound louder. IS louder on the meter.

If you're chasing numbers, in my experience, 2 12's are better with everything else being equal. I AM chasing numbers, so it's worth it.

If this is just a daily setup that you're not competing with, it won't make a bit of difference.

sounds like motor force, but i could be wrong as im nowhere near as smart as some people

i just noticed the same effect with a sub with motor force which is why i say that

 

[TRaGiK 10+ year member]

sounds like motor force, but i could be wrong as im nowhere near as smart as some people
i just noticed the same effect with a sub with motor force which is why i say that

More cone area, more motor force...more dB's. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Don't know what makes more difference (cone area or motor force). Don't care either. Just happy with the gain...which I expected to get before switching. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[kr15 5,000+ posts]

So here's my experience as of today on this exact topic.
I own a termlab with the clamp so I can check wattage.

Equipment is 2 DC Audio 2.0k amps, strapped at a half ohm per amp in the trunk of a 2003 Civic. Box dimensions are identical. The only differences in the boxes are single 15 was left side port, and the 2 12's have a center port. Both use a single, external, aero port.

Sub is/was DC Audio XL 15, and 2 DC XL 12's.

I tested as follows:

Car sealed, meter on the glass, keeping power under 2500 watts

Car sealed, meter on the glass, unlimited power

Drivers window down, meter in the kick, unlimited power

On 2300 watts, car sealed, 2 12's got me a .8db gain.

On 3500 watts, car sealed, I gained .7db.

Outlaw, I only gained .3db, BUT I ran out of time and wasn't able to do as much testing as I wanted/needed. I'm confident I'll get another .4 or so out of it. More testing with that later.

To the ear, there is ZERO difference. However, the car is more windy with the 2 12's. May just be port location, but the difference in felt wind is significant. Feels louder. Does NOT sound louder. IS louder on the meter.

If you're chasing numbers, in my experience, 2 12's are better with everything else being equal. I AM chasing numbers, so it's worth it.

If this is just a daily setup that you're not competing with, it won't make a bit of difference.

Thats pretty much been my experience too... having been competing for 8 years and having alot of meter time during that run.