Discussion in 'OT Technology' started by M-1000, Aug 14, 2002.
1 12" and 2 10", or 2 12" and 2 10"?
if they are the same model subs etc there would most liley be a difference but say you compared 2 any brand 10s to say one id max 12 the 1 12 would outperform them easily..
i just did one guys car he had 3 jl w6 10s in there with an xtant 1001dx and i set an id max 12 in a sealed 1.5 cu ft box in there and hooked it up it was louder and much tighter than the 3 10s
but it really depends on what you comparing size isnt the only factor any more
alpine type-r 10's or 12's. i can get them both for $250 cdn/each. how much does 1 idmax 12 cost?
The main difference is surface area. The general rule is more surface area = louder. This is not always true. Depending on how many watts the subwoofer is and how thick the surround is the sub will be louder or not.
LOUDNESS ISN'T ALWAYS GOOD!
8" & 10" = Subs made for Sound Quality (someone who wants to let the bass complement the rest of their system but not overwhelming). Getting subs that need 250 Watts to 400 Watts RMS (constant power) work well in this situation. Smaller area and thinner surround will respond faster. Good for people who listen to Rock, Jungle, or Drum n Bass music.
12" = The average size most people buy. More loudness a little less Sound Quality. Can range from 400 Watts to 1800 Watts. Good for people who listen to Heavy Metal, Rap, or Trance/Techno.
15" & Greater = Made for loudness. Can range from 400 Watts to 5000 Watts!! Only useful to those who listen to Rap or compete in SPL (Sound Pressure Level aka Loudness) contests.
The bigger the cone is, the slower it will respond. If you listen to music with frantic drums or basslines that change frequency often then stick with 10". Punchy and Moderately-paced basslines are handled well by 12". Extreme low-end bass is well suited for 15".
When listening to fast paced drum n bass or rock drums you can tell when a 15" or 12" might miss a beat. I suggest getting 12" subs unless you think otherwise. Subs don't always have to be bought in pairs. So if a salesman tells you they do, tell him bullshit. You'll save money by building a box for only 1 sub and you can get an amp and "bridge it" to get more power out of it. If it is a 300x2 amp you could most likely get 600x1 or greater out of it.
These are General Rules to follow when buying your first "system" you'll get into brand names more as you increase your knowledge about car audio. PS - Don't buy anything that is Pyle, Sony Xplod, Jensen, Rampage, or Pyramid because you'll regret it in the long run.
feed tehm enough power and they will all move fastenough to produce music the 8s and 10s are closer in size to the midbass so there is less of a chance of there being a gap in teh freq curve 12s imo are the best you can still get enough low end to go past teh limits of your hearing but dont have the lack of lowend and less output of the 8s-10s teh 15 is ok but you almost need an 8 or 10 to cover the hole in the freq curve but you will get awsome low end response and volume
but if you want the sub quieter picking the sub size has little to do with it jsut cut the power to sugb it will thus be quieter just becasue a sub is louder dosent mean it has to be
First of all, the surround has NOTHING to do how loud the driver is, or how loud it will be.
Your theory about larger diameter subwoofers responding slower than smaller diameter ones is COMPLETELY WRONG. That entire list is WRONG. Sorry, but that is a POOR deciding factor.
The power ratings you include with each size is incorrect. Power rating is a measure of the thermal and mechanical capabilities of a driver in regard to a specific amount of time. I could feed an 8" woofer 2000w for 1 second, and it might be fine, while I could feed an 18" woofer 200w for 24 hours, and it might be melted by the time we were through.
Using a 12" or 15" woofer will not miss any beats. You can get a 6.5inch subwoofer to sound sloppier than an 18" one. The enclosure the driver is in makes a huge difference on how the driver will perform, also, the car's interior plays a huge role.
I Dunno but the little physics I know will support the Idea that a larger surface will travel slower over the same distance when giving the equal amount of power as the lesser.
Sorry, but that is just incorrect....
While one might logically think that would be the way it works, it is not, as the cone mass has more to do with this than the diameter. You could have an 8" woofer with an extremely high mass cone and a 15" woofer with a low mass cone. The 15" would logicallly move back and forth easier than the 8". but that is still not true. If you feed a loudspeaker a signal, it will play it back, simple as that.
There are prosound loudspeakers that use 15" drivers as the bass section and they are used all the way up to 2khz. That is OVER 4 OCTAVES HIGHER THAN THE RANGE A SUBWOOFER PLAYS!!! How would that even be possible if your theory is correct?
Any speaker that is designed correcly will play back the input signal as it was created. Yes, there will be distortion on top of that, but you will not loose any cycles, because if you do, when input a certain frequency such as 50hz, you would have an output of say 40hz. And I have NEVER heard of that happening. The only place I could possibly think this could occur is if the driver's motor structure was EXTREMELY WEAK AND POOR.
Inside a loudspeaker there is a coil of wire and when current is applied, either of negative or positive polarity, the coil of wire will move forward or backward. The coil will always have a lag between when the current first hits it, and when it starts moving, but it is negligible.
Ok, let me try and give an analogy here. It will make things easier to understand.
Imagine you have two cars, a Big pickup with a V12 engine, and a small compact with a 3CYL one. Pickup gets 10mpg, and compact gets 40. Now both cars can drive at a speed of 60mph, right? The difference between the two is that the pickup is much heavier than the compact. Relate this to the mass of the cone. It can still go the same speeds as the compact, but it is not as efficient. Same thing with speakers. Those with very heavy cones are going to be less efficient, which means for every watt you give them, they produce less output than their counterpart. Now, when you get low in frequency though, that extra mass becomes good, because the driver can go much lower in frequency than the smaller one.
That is a flawed analogy, because I am not taking several factors into account. But it for the most part describes the situation you all are desscribing.
I guess I was wrong about the moving slower thing. The only reason I said that is because I took a John Tab CD (jungle/drum&bass) to Hifi Buys and was trying to decide whether to get an IDQ 10" or a IDQ 12" DVC. On one part of a bassline the twelve skipped one beat in order to keep up with the rest of the song. The 10" handled it perfectly. I never took into the equation of what wattage amplifiers they had powering each.
Help me out and explain how a 12 or 15" could keep up as easily as a 10". I'm looking to put new subs in my car and I would buy a 12" or 15" if it could keep up. I guess the one experience threw off my view on the subject.
12s and 15s have larger voice coils so they have more force being applied to teh cone this is not always true feed any sub enough power and as long as teh it dosent destroy it self it will play any not within its abbilty i could see if you had a 15 with 50 watts of power and ahving trouble hitting lower notes as far as skipping a beat its flat out not possible you are hearing things teh box has more to do wiht the frequency response than teh sub does
The diameter of the voice coil has nothing to do with appling more force to the cone. The BL is the measure of magnetic field strength. You can obtain a high BL several ways. First, use VERY thin wire, so that you can fit many layers in the magnetic gap. The downside to this is that your maximum power handling is limited. Another way is to use a very thin magnetic gap which will allow a very high BL force within the linear range, but your maximum excursion will be compromised. Its just a difference of design goals.
Larger diameter voice coils are used only for better heat disapation. An example to this is that my friend has a 2.5" diamter voice coil in his loudspeaker that is 15" in diameter. It is a prosound driver that has a sensitivity of 100dB at 1w/1m, and I have a subwoofer driver with a 3" diameter voice coil that is 18" in diameter. The subwoofer only has a sensitivity of 93dB 1w/1m. That is quite a large difference but it is understandable. It goes to show however, that the larger diameter voice coils do not infact make for more loudnes. What controls the cone electrically speaking is the driver's QES or electrical damping. A higher QES means the driver has less cone control. It shows the ratio between reactance and resistance at the drivers resonant peak (you know the FS) only regarding the motor section. It does not include the suspension losses as they are calculated for in the QMS rating. The combined total of both the QES and QMS is the QTS. QES is related to BL as it is inversly proportional to the square of BL, so if you double your BL your QES is quartered. That would mean the driver would have 4 times the control as one with half of its BL. THIS is what causes the driver to have more control, not the diameter of the VC or the size of the cone.
I still dont know exactly what you mean by "skipping a beat".
The reason the 12 or 15" can keep up as easily with the 10" is because as I replied to flynfrog's post it is due to the damping along with BL (motor strength) that determines this. The enclosure as he also said does have more to do with the sloppy sound than the driver itself.
Some of the world's most expensive subwoofers use GIANT drivers, such as the Wilson which uses the Aura 1808, which is an 18" driver. It will sound as "tight" or "quick" as any small diameter subwoofer.
skipping a beat meant instead of the bassline going "BOOM BOOM BOOM bah-boom bah-boom bah-boom-boom"
The 12" made it sound like "BOOM BOOM BOOM bah-boom BOOM BOOM"
Hence, skipping a beat or a few frequencies because the sub either took longer to respond or the 12" might not have been matched up with a powerful enough amp
Take into account that when I listened to the subs the display could only play 4 subs at a time (that might have factored into the reason that I could hear the beat with 2 10" compared to 4 12") I would love to just run a single sub setup (15" preferred) that can keep up with the faster-paced music I listen to. Along with the upbeat, diverse basslines drum n bass also has many bass drops that hit extremely LOW and I know the 15" could hit those well. The ability of the 12" speakers that I've heard so far to grab those few extreme drops hasn't impressed me. I'm look to spend no more than $250 on a 15" maybe you could suggest some woofers for me?
Back to the original question, it's all install. It's not just the subs, the amp that's powering them, the electrical system that's powering the amp, and the enclosure the sub is in all make the difference. For example, I was at a show and saw a guy with 8 12s do a 147 when I was pulling 149-150 with 1.
i rember back on teh SD caht some guy was getting beat by a guy who had all radioshack subs liek 24 of them but by teh end of the cometiton he only ahd 10 left casue they kept blowing
just shows how much install maters i dotn think you could get away with that now to many drivers built jsut for spl with crazy amounts of power
people are hittign 170 with 1-15 now so its not realy all that impressive
1 15' has more surface area than 2 8's
there also alot of differnce between 156 and 170
156 is actually somewhat bearable to sit in, but 170 will make your heart stop. The loudest I've ever sat in was 161s with ear protection and it hurt.
It was probably due to either the driver's being severly clipped, bass boosts installed, phase issues, poor enclosure(most likely) etc.
If you have 250 to spend, you could get a tempest or dayton dvc 15" for around 150 dollars. You would have an extra 100 left over. Both drivers have high output, and when placed in the proper enclosure will sound very accurate. My brother has two Dayton dvc 15" in his car in an SPL install (so it sounds bad but is very loud). They have a ton of output, so that wont be a problem. As for the sound qualtiy, like I said, you put them in the proper enclosure and they will sound as "tight" as an 8" woofer.
Very true 156 to 170 is life or death
I just find it fascinating that 2 8's (which are tiny) could give that db output and take 2k watts at the same time.
1 15 that would knock you unconscious is pretty hot to but I don't have room in my car for 15's
they were feedign the 1 15 5000 watts rms i think