More cone - how much more SPL?
 

say someone has 2 10's.

but enough power to effectively run 4 10's.


then they add 4 more 10's, totaling 6.


if power stays the same, how much gain in SPL, theoretically, should a person expect?

would it be better to stay with 4 10's since that is the number of subs that can be adequetly powered? Or would having 6 slightly underpowered subs still be louder?

Theoretically given the same power with 2x cone area is supposedly 3 db gain. however with 3x the cone area one would assume a theoretical 4 db gain. however i think a 2 to 2.5 gain would be more realistic.

I just experienced this exact scenario last week.
Testing 1 sub then adding a second gained 5.2 dB then 2 subs up to 4 subs gained another 3.4 dB then 4 subs to 6 subs only gained 0.8 dB. At this point i am seriously under powering like 1200 watts per sub.

I know in extreme going from 18" sub to a 15" sub is only 0.2dB difference. The gain isnt in cone area but motor strength.

this is a odd question coming from you Iolui, you should know this stuff.

so you saying 4 10's is good enough.

I think if you ridin spinnas then you are golden!!!
What iam saying is i gained 0.8 from 4 to 6 subs.

well i do ride spinazzzz cuz my eyes like a chinese im drinkin on the heiny riddin down the strip any part at you can find me...

Yuli, I think we'll see a nice gain ;)

Yuli I have found it really depends on the vehicle and sub placement.

I have seen little to no gain to 5-6db gain

But since your doing it I say you see a big gain with your experience.

Garett

It is hard to say what the gain will be because of other variables. If you are going from 4 to 6 subs and you are able to give them the same power then I would predict up to a 2 db gain. But if you are adding 2 subs and not increasing power so that the 6 subs are getting the same individual power as the 4 were then the increase could be nullified because you are trading cone area for power.
If it is in your rex, you have to consider the change in flow and increase pull in power to get the amps to make full power and see a gain. But you are a smart guy Yuli, you will figure it out.

well i know space becomes the biggest issue and a proper box becomes the biggest factor.

so say someone goes from 2 subs to 4 subs. with enough power to push 4 subs. what is the theoretical gain there? 1.5 db's?

If you are going from 4 subs to 6 subs and nothing else changes (except box volume) then the theoretical difference is 10 x log 6/4 = 1.76 db

lol no. im going from 2 subs to 4, or possibly 6.

i was thinkin of goin from 2 12s to 6 10s but that is to expensive

double cone and double port is 2db

double power is 3db - double actual power output from amp and as long as the sub can hold it

mtx audio's website has a way of doing this and this is how i know it. in order to find your volume displacement is what your looking for you need to know your X-MAX and Sd (Cone area). you multiply Xmax x Sd and get you volume.

a 10W7 has a Sd of 59.8 inches squared and an Xmax of 0.91 inches. multiply and you get 54.2 inches cubed and that how "loud it will be". 4 of them however are 11.85 db louder than one and 6 would be more than 3 db louder than that at 15.35 db.

if that makes sense... if not... MTX - Volume Displacement

hahahahaah mtx is a joke

I would agree on this one with the exception that excursion plays a vital role in how much your gonna gain. But all things being equal I would say go with 4 and double the power, then do 6 and more power. I think 4 would be the bigger of the gains but overal 5-7 db louder than the 2 with the 3x less power. If its for bass race, go with the 6. Nothing will beat more coils to handle the heat in bass race.

i got kinda the same question, if i was one 10 with well enough power for two 10's how much more dbs will a seconde 10 give me roughly?

1.5 to 2 db's.

ok.... i just went from 4 - 350rms subs to 2- 800rms subs (10's) and 1000 watt rms amp. should it go up or down in db? the 4 subs were pointing up at the trunk and the 2 are pointing forward into the car. i haven't miked the 2 yet but the 4's port was tuned to 35 htz and the 2 are tuned to 50 htz. what should the outcome be? port tuning should be key...right?

I think 4 tens in your rex would hurt the pressure flow. 3 tens would gain i bet but 4 tens would be slim to nill, givin the same ammount of power. How much do you gain from 1 sub to 2 subs with the same power?

about 1.5 db's.

I roughly figured out 3subs would be aproximently 0.6 to 0.4db and the 4th sub about 0.1 to 0.2db, assuming the pressure flows equally around the boxes.