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View Full Version : 2 subs vs 4 subs which is louder and enclosure style



sk8rfiero
10-03-2013, 05:03 PM
Originally I planned on having a pair of Orion HP 12s, with dual 4ohm coils, paralleled down to 1ohm in a ported box. My oldschool Orion HCCA250 would give them approx. 800W. Today I came across another pair of the same subs(identical specs) in a sealed box. So here are my questions????

1. Will (2)12s at 800W(1ohm) be louder AND create more air pressure than (4)12s at 400W(2ohms) given they both use the same cu in airspace per sub?

2. What are your opinions on mixing a sealed & ported box in the same SUV?

3. If I paralleled all the 12s down to 0.5 Ohms , what are your thoughts on adding (2)4ohm 8's paralleled onto the 0.5 that'd give me 1.5 ohms ? Mathematically this works but not sure it's practical?

My goal is to increase audible volume & air moment. I'm open to any suggestions using the equipment I already have. Thanks.

NIHL8ION
10-03-2013, 05:09 PM
Originally I planned on having a pair of Orion HP 12s, with dual 4ohm coils, paralleled down to 1ohm in a ported box. My oldschool Orion HCCA250 would give them approx. 800W. Today I came across another pair of the same subs(identical specs) in a sealed box. So here are my questions????

1. Will (2)12s at 800W(1ohm) be louder AND create more air pressure than (4)12s at 400W(2ohms) given they both use the same cu in airspace per sub?

2. What are your opinions on mixing a sealed & ported box in the same SUV?

3. If I paralleled all the 12s down to 0.5 Ohms , what are your thoughts on adding (2)4ohm 8's paralleled onto the 0.5 that'd give me 1.5 ohms ? Mathematically this works but not sure it's practical?

My goal is to increase audible volume & air moment. I'm open to any suggestions using the equipment I already have. Thanks. If you want to run 2 more 12's get another 250r or g4 whichever you have now, or just get one amp to power all 4 adequately and build a custom enclosure for all 4 either way... Do NOT mix different sub sizes - NOT a good idea at all. Otherwise I'd just leave it as it is... Running 4 12's on half the power @ 2 ohms seems like a waste to me IMO

fasfocus00
10-03-2013, 05:47 PM
There is no replacement for displacement. All things equal displacement wins. No mixing this isn't a smoothie shop. You should stay in school and pay attention in math class.

jrdnhsnbrg
10-03-2013, 06:07 PM
Build a ported box for all 4 subs if you want loud and get another amp. DO NOT MIX subs. Baaaad idea.

ewadz3006
10-03-2013, 06:37 PM
As said do not mix subs.


Seems like you are a enough is not enough type of guy like the rest of us. I would get the other 2 subs, and upgrade you amp. if you can't afford a amp now, you could just run two of them till you get more power. Then build a proper box (for all four subs)and wang out.

As far as two subs on higher power being more or less loud than four subs on less power, I can't answer that.

basswiigee
10-03-2013, 06:46 PM
yeah just build a box for the 4 12's and get a good amp... i agree with alot of these comments yet i too before have ran mixed subs and been surprised by the out come... 10's and 12's... but even though it sounded good if properly done and not mixed it would've sounded better...

sk8rfiero
10-03-2013, 11:14 PM
Thank you for the responses. I look into box designs ( most people are doing subs up /port to the back right?) I know some of you mentioned getting a new amp to run all 4 12s. I understand what you mean. What size were you guys thinking? Keep in mind I'm "not sponsored by mommy & daddy".lol

NIHL8ION
10-04-2013, 12:10 AM
Thank you for the responses. I look into box designs ( most people are doing subs up /port to the back right?) I know some of you mentioned getting a new amp to run all 4 12s. I understand what you mean. What size were you guys thinking? Keep in mind I'm "not sponsored by mommy & daddy".lol Find yourself a nice used Sundown SAZ-1500v3 and wire it to .5, or if you want to go the cheap rout get a Power Acoustic BAMF 5500 and wire it to 2 ohms :cool:

UsAmpsFreak
10-04-2013, 12:13 AM
Hey there, both ways will be the same volume. If you double your power you will usually experience a 3db gain, in the same token, if you double your cone area you will also gain 3 db. So, if you double your 12's by going from 2 to 4 that is a 3db gain hypothetically, but by doing that you will cut your power in half which will basically make going from 2 to 4 pointless. I would just stick to the 2 12's and run your amp and it's potential. Otherwise like some other posters have said perhaps you can get a new amp for all 4 to run at it's max power at the proper impedance but otherwise i'd just do the 2.

sk8rfiero
10-04-2013, 12:38 AM
Just unscrewed the new set out of the box and realized that they are 2ohm DVCs, my originals were 4 Ohm DVCs. Good Grief! Per Orion spec sheets for the HP12d2 & HP12d4 the specs are slightly different. Back to the drawing board.

sk8rfiero
10-04-2013, 01:27 AM
Hey there, both ways will be the same volume. If you double your power you will usually experience a 3db gain, in the same token, if you double your cone area you will also gain 3 db. So, if you double your 12's by going from 2 to 4 that is a 3db gain hypothetically, but by doing that you will cut your power in half which will basically make going from 2 to 4 pointless. I would just stick to the 2 12's and run your amp and it's potential. Otherwise like some other posters have said perhaps you can get a new amp for all 4 to run at it's max power at the proper impedance but otherwise i'd just do the 2.

So in theory.... if I started with (2)12 at 180W ...then (4)12s at 360W =gain 3db..... then (4)12 at 720W =additional 3db ..=total gain 6db
would be the same as ..............(2)12 at 180W....then (2)12s at 360W =gain 3db......then (2)12 at 720W =additional 3db ..=total gain 6db

So why do people run 4 subs? Is it only cause they're maxing out the watts on each sub? I would have thought that (4)12s at 720W would move more air (based on surface area) than (2) at the same wattage. Does the longer excursion of the(2) subs make up for the smaller surface area?

NIHL8ION
10-04-2013, 01:49 AM
So in theory.... if I started with (2)12 at 180W ...then (4)12s at 360W =gain 3db..... then (4)12 at 720W =additional 3db ..=total gain 6db
would be the same as ..............(2)12 at 180W....then (2)12s at 360W =gain 3db......then (2)12 at 720W =additional 3db ..=total gain 6db

So why do people run 4 subs? Is it only cause they're maxing out the watts on each sub? I would have thought that (4)12s at 720W would move more air (based on surface area) than (2) at the same wattage. Does the longer excursion of the(2) subs make up for the smaller surface area?

Whenever running ANY amount of subs why not run them at their potential? YES - You would have more cone area with the 4 subs vs 2, however with half the power you are running right now odds are all of that work is not going to seem worth it in the end - PPL run 4 or more subs because they are powering them to their limits and want to get everything they can out of them... More excursion does make up for displacement to a point, hard to say in your situation though with the subs and power you are talking about - results would seem to me to be mediocre at best... I'd continue running your pair you have now @ 1 ohm and take those other subs and exchange them for D4 coil subs as NOW with this being said - You can't really run them al together now anyway as they are different impedance - Unless you get a separate amp and match output voltage on them for the power you have at the given impedance for each set so they output the same rms, but I really wouldn't go that route, just get the right subs and a bigger amp, build yourself a custom ported enclosure for all 4 and then call it a day :cool:

wickedwitt
10-04-2013, 02:00 AM
Cone area is almost always more efficient than power. Running 4 on 400w is going to be louder than 2 on 800w in a proper enclosure. As you approach the limits of the sub, heat buildup causes losses. This is overcome by adding subs and distributing the power across more coils, giving you not only more cone area, but more motor force and therefore displacement. Displacement is what moves air and builds pressure.

There are exceptions to this rule of course (like typically you can get louder with 8-12 subs than you can with 30 subs) but typically that is a loading and space constraint issue that causes this.

Do the 4, it'll be louder. One day down the road double your power, it will be noticeably more so.

NIHL8ION
10-04-2013, 02:08 AM
Cone area is almost always more efficient than power. Running 4 on 400w is going to be louder than 2 on 800w in a proper enclosure. As you approach the limits of the sub, heat buildup causes losses. This is overcome by adding subs and distributing the power across more coils, giving you not only more cone area, but more motor force and therefore displacement. Displacement is what moves air and builds pressure.

There are exceptions to this rule of course (like typically you can get louder with 8-12 subs than you can with 30 subs) but typically that is a loading and space constraint issue that causes this.

Do the 4, it'll be louder. One day down the road double your power, it will be noticeably more so.

I agree with everything you just said - In his case though I doubt the difference in output running only 400 rms to all 4 of them will be all that much of a gain... THAT - AND the fact that he has 2 - D2 subs and 2 - D4 subs now = I wouldn't run them on the same amp = NFG (NoFknGood) Although if this is his plan and he's going to stick with it, I would build a custom enclosure for all 4 and swap out the new ones for the correct VC configuration and then run them all on the 400 rms @ 2 ohms his amp will do untill he upgrades his amp, But I wouldn't just throw 2 more subs back there in a pre fab enclosure and hook em up - Not worth it IMO = Not much of a gain will be noticed for all of the effort ;)

UsAmpsFreak
10-04-2013, 11:03 AM
Well i've seen some people on here telling you that cone area will always beat power, personally in my 15+ years installing i'd have to disagree. Power has always been the most important thing to me. I'm sure you've heard many systems with only 2 woofers that blew away other vehicles with a lot more woofers. Sometimes this can be attributed to having a bad box design or some other variables but more often than not they have overdone it one woofers and not put the proper power on them or are running them at weird impedances that don't match well with the amp. In theory doubling your cone area is exactly the same as doubling your power (as long as your woofers can continue to get louder with more power, if they have hit their peak you can add more power and it won't make them any louder, depends on the sub).

jrdnhsnbrg
10-04-2013, 11:15 AM
Originally I planned on having a pair of Orion HP 12s, with dual 4ohm coils, paralleled down to 1ohm in a ported box. My oldschool Orion HCCA250 would give them approx. 800W. Today I came across another pair of the same subs(identical specs) in a sealed box. So here are my questions????

1. Will (2)12s at 800W(1ohm) be louder AND create more air pressure than (4)12s at 400W(2ohms) given they both use the same cu in airspace per sub?

2. What are your opinions on mixing a sealed & ported box in the same SUV?

3. If I paralleled all the 12s down to 0.5 Ohms , what are your thoughts on adding (2)4ohm 8's paralleled onto the 0.5 that'd give me 1.5 ohms ? Mathematically this works but not sure it's practical?

My goal is to increase audible volume & air moment. I'm open to any suggestions using the equipment I already have. Thanks.

I just looked up the specs of the sub, they're only rated at 500W RMS. 800 might blow them, if you do only hook up 2 keep your gain down.

UsAmpsFreak
10-04-2013, 11:24 AM
800 watts of clean power won't blow subs rated for 500 watts. Clipping an amp that is 800 watts on subs rated for 500 watts will. As long as he stays within the limits of the equipment he'll be fine.

jrdnhsnbrg
10-04-2013, 11:27 AM
800 watts of clean power won't blow subs rated for 500 watts. Clipping an amp that is 800 watts on subs rated for 500 watts will. As long as he stays within the limits of the equipment he'll be fine.

I just wasn't sure. Never worked with Orions or old school equipment like he says he has for an amp.

UsAmpsFreak
10-04-2013, 11:35 AM
Yea it's cool man, you can damage a speaker from giving it too much clean power but you have to go way off the map to do it. I have run many systems with double the power as what they are rated and as long as you aren't sending distortion to them they always hold up. In fact my last system i had 4 Re Audio SR 15's which i believe were rated in the 500 watt area and i ran 2 UsAmps Md2d's strapped together on them. Which is obviously a lot more power than they were rated to handle. Clean power is the key, and it rarely blows subs unless you just go nuts with it.

jrdnhsnbrg
10-04-2013, 11:39 AM
Lol like if I hooked my Hifonics BRX1600.1d (1600W RMS@1 ohm) to a DVC 2 ohm 8" sub rated at 300W RMS... That MIGHT blow it I'm not sure. ;)

UsAmpsFreak
10-04-2013, 11:53 AM
lol, yes, that is going a bit too far with it and you'd probably smell the sub begging for mercy shortly. But in most cases the idea of "blowing a woofer with too much power" is really not very accurate.

bbeljefe
10-06-2013, 02:43 AM
Originally I planned on having a pair of Orion HP 12s, with dual 4ohm coils, paralleled down to 1ohm in a ported box. My oldschool Orion HCCA250 would give them approx. 800W. Today I came across another pair of the same subs(identical specs) in a sealed box. So here are my questions????

1. Will (2)12s at 800W(1ohm) be louder AND create more air pressure than (4)12s at 400W(2ohms) given they both use the same cu in airspace per sub?

2. What are your opinions on mixing a sealed & ported box in the same SUV?

3. If I paralleled all the 12s down to 0.5 Ohms , what are your thoughts on adding (2)4ohm 8's paralleled onto the 0.5 that'd give me 1.5 ohms ? Mathematically this works but not sure it's practical?

My goal is to increase audible volume & air moment. I'm open to any suggestions using the equipment I already have. Thanks.

Answers:

1: Theoretically, halving the power and doubling the piston area will not change output. In reality, more motors being able to run cooler will net a slight increase, albeit inaudible in most cases.

2: Not a good idea if the drivers are like and kind on the same power. You could add a smaller sealed sub to a low tuned bandpass box to replace the loss of upper sub bass but in an all other things being equal scenario... the sealed box won't make an audible difference in sound quality and likely won't make an audible difference in sound pressure.

3: Your math is incorrect. If you run a .5Ω load in parallel with a 2Ω load you are creating a .4Ω load. If you can't remember (or don't know) the formula for parallel resistances, the final load will always be lower than the lowest resistance. Thus, you can add a 1000Ω load in parallel with a 1Ω load and the result will still be less than 1Ω.

And to achieve your goal... sell two of those woofers along with both boxes and build a wave t-line for the two you keep. :-)

bbeljefe
10-06-2013, 02:49 AM
Yea it's cool man, you can damage a speaker from giving it too much clean power but you have to go way off the map to do it. I have run many systems with double the power as what they are rated and as long as you aren't sending distortion to them they always hold up. In fact my last system i had 4 Re Audio SR 15's which i believe were rated in the 500 watt area and i ran 2 UsAmps Md2d's strapped together on them. Which is obviously a lot more power than they were rated to handle. Clean power is the key, and it rarely blows subs unless you just go nuts with it.

Another thing to keep in mind is cooling. You can triple the rated power on a coil so long as you can keep it cool. Heat energy is what melts wire, not motion. So obviously, not reaching mech max is also a huge factor.

And if iirc, the SR is a 400 watt sub.

wickedwitt
10-08-2013, 11:53 PM
Well i've seen some people on here telling you that cone area will always beat power, personally in my 15+ years installing i'd have to disagree. Power has always been the most important thing to me. I'm sure you've heard many systems with only 2 woofers that blew away other vehicles with a lot more woofers. Sometimes this can be attributed to having a bad box design or some other variables but more often than not they have overdone it one woofers and not put the proper power on them or are running them at weird impedances that don't match well with the amp. In theory doubling your cone area is exactly the same as doubling your power (as long as your woofers can continue to get louder with more power, if they have hit their peak you can add more power and it won't make them any louder, depends on the sub).

Regrettably, that is almost always thanks to bad box design. You have to break well over 1000 sq. in. of cone area in order to start getting diminishing returns on cone; which again boils down to box because you run out of proper airspace for each.

This is coming from a guy that runs 2 15s on 10k, but I could move way more air with 4 15s on 10k than I could adding 10k more in power. Just sayin'.

UsAmpsFreak
10-10-2013, 02:24 PM
Regrettably, that is almost always thanks to bad box design. You have to break well over 1000 sq. in. of cone area in order to start getting diminishing returns on cone; which again boils down to box because you run out of proper airspace for each.

This is coming from a guy that runs 2 15s on 10k, but I could move way more air with 4 15s on 10k than I could adding 10k more in power. Just sayin'.

While i don't completely disagree with you i do to a point. If cone area was the end all answer for being louder then every single spl record holder would be the next alma gates with a million subs. Power is just as important, if not more important. It's why you see most serious spl contenders with only 2-6 subs with an insane amount of power of them. Well, that's my take anyways.

wickedwitt
10-10-2013, 03:14 PM
While i don't completely disagree with you i do to a point. If cone area was the end all answer for being louder then every single spl record holder would be the next alma gates with a million subs. Power is just as important, if not more important. It's why you see most serious spl contenders with only 2-6 subs with an insane amount of power of them. Well, that's my take anyways.

We aren't talking about tricking an O2 sensor here, we're talking about listening to music daily and displacement is going to be louder to the ear than the force behind a smaller amount of displacement. I agree with the fact of low number of drivers for SPL, and it's more impressive to be loud on a few cones; for most people it's easier to gain musical output by simply doubling cone area. It's also cheaper as it doesn't require most electrical.

UsAmpsFreak
10-10-2013, 07:46 PM
We aren't talking about tricking an O2 sensor here, we're talking about listening to music daily and displacement is going to be louder to the ear than the force behind a smaller amount of displacement. I agree with the fact of low number of drivers for SPL, and it's more impressive to be loud on a few cones; for most people it's easier to gain musical output by simply doubling cone area. It's also cheaper as it doesn't require most electrical.

That's true up to a point. That's what i'm saying. Once you have graduated into top of the line equipment the idea that cone area trumps power is IN MY EXPERIENCe not the case.