Not happy with my bass response

Flyin11

Member
2007-09-26 1:29 pm
Well, I don't think I'm getting enough bass out of my subs so I'm looking into some options which include maybe going for 1 15" to get that more intense bass kick for my music. I just don't know if 1 15" will sound better than my 2 12's or if it will be more muddy sounding. Power to the sub is not a issue as I'm looking at a 15W4-D2 JL Audio and it says 200w RMS and the amp I have is putting out around 375-400 @ 2ohms with wire length loss and all.

Have also been considering getting 2 8ohm 10" Kickers and wiring them in parallel inside the box, adding that to my other 10" 4ohm I have at home to make 3 10's and then wiring them all in parallel outside the box for a 2ohm load and having 3 10's.

I'm also maybe looking into just getting a really good quality custom box made as maybe it's my enclosure that isn't producing the bass I'm looking for.

What else can I do? Does the 1 15 sound like a good way to go?
 
If I am correct, 1 15" equals 2 12" for surface area. What 12"ers do you have and what size of box are they in? Is it a ported box or sealed? What kind of music do you listen to?

In standard rock, the low E on a bass guitar is 40Hz and a kick drum is sounding around 60-100Hz. So 2 12"ers should be able to pound this out easily. Dance and Rap and other stuff like that will have a lot of energy down to 20Hz as well, so 2 15"ers or something might be needed to give that authority but 2 12"s should still make it decent enough.
 

Flyin11

Member
2007-09-26 1:29 pm
Maybe I need to look for 2 12's that have more handling power then? Not sure...JL's are expensive and I thought I was getting great quality out of the ones I have but I might have to go to another brand like MTX, Kicker, or Rockford....

I have a 2003 Honda Civic EX coupe and I only listen to rock. I have 2 JL Audio 12W2v1 SVC subs and they are 4ohms wired in parallel for a 2ohm load in a sealed enclosure with 1.27cu ft of air space. The enclosure has the subs facing the back of the car towards the trunk, it's just a simple rectangular enclosure (Not rear firing, wedge, or slanted). I tried turning them around once and it sounded awful like that. Plus, I need to have them like this so I can mount my amplifiers and stuff on the back of it. The subs are rated at 150rms each so that's 300w for 2 and I'm not in any danger as the gain is not up into the high range. The amp is a Rockford P300-1 mono amplifier but it's certified to put out 431w @ 2ohms at 14.4v. After power loss from power wire length and all, it's really only putting out about 380w max. So, I think I'm good to go on the amplifier.
 

Flyin11

Member
2007-09-26 1:29 pm
Power estimate loss came from Perry's site under the wire section. I agree with what his site shows as the only way you can even get close to full rated power is if you have it at max power.

Cubic volume is per chamber...

I guess by audio source you mean headunit...I have a Kenwood Excelon KDC-X891 5V. Nothing wrong with it and I love the headunit.
 

Flyin11

Member
2007-09-26 1:29 pm
Just saw a tutorial on YouTube someone was doing with a 8" sub last night he was saying because he like a lot of bass in his rock he sets the crossover at 100hz on the amp, maybe a click more. Got me thinking about that but I don't go that high. I like it around 60hz or 80hz and 80 didn't sound all that clean.
 
Might be the case of wrong speakers for the application. In WinISD, these things are -3dB down at 60Hz and -9dB down at 40Hz. -3dB down means half as loud, so when it hits 40Hz, its 1/8th as loud then anything else at the flat level. I don't know much about cabin gain in a car but this seems relatively low to get a big thump, thump out of them.

So you need to either increase the bass in the box you got by equalization, or have vented boxes built for you.
 

Flyin11

Member
2007-09-26 1:29 pm
What do you mean by equalization?

Yeah...I started to think about a ported box but I've always heard that a sealed box was the best choice for rock music and that ported sounded like junk with rock. I have a ported box that I got from Crutchfield with a couple 12" Punch Stage 1 subs a while back so I might grab that and see what it sound s like with the subs in there. I don't think it meets the specs for a ported box with these subs but it's worth a shot. The punch subs sounded pretty good when it was in there but the kick drums sounded like they were flat and echoing. You heard more bass but lost the kick from the kick drums. Like I said before though...That was a angled box....So maybe I need to try a box that is angled and sealed?
 

jpruden

Member
2007-09-13 4:57 pm
Hi again, Flyin...

Maybe you could give us an example of some specific songs that you're having difficulty with... I'm finding it pretty hard to fathom that you're not getting enough bass from your setup. It could be that the songs just don't kick.

I'm running a single JL 12w3 on a JL Audio 500/1 and on the right song, it will chase me out of the car. The gain on my amp is turned down so I'm definitely not using all of its available power.

The real difference between your amp at 400 watts and my amp at 500 is actually pretty small, so there *must* be something else going on...

smiles,
Jamie
 

Flyin11

Member
2007-09-26 1:29 pm
It's not just one song that I listen to...I listen to a range of different ones. I know all songs are different and some will make you run for cover. I'm just trying to find that neutral sound so that if I want more bass or something I can do it from the front seat on the headunit but it's just not working out. I'm not feeling a lot of it up front and it's not making me say "WOW, that's what I'm talking about". If I up the gain, it's then too much, and if I turn it down, it's not loud enough. I'm not feeling the bass too much from the songs. When I get my highs straight up front that's going to take some more away as well. I'm thinking I might need to try a angled enclosure so that I try and get the sound to come back to my upper part of my body instead of around my legs.

I want it to hit harder but it's not working out that way......
 
Equalization is the process of making all things equal.

Now for an answer that doesn't make me sound like a smart a**.

I said that 40Hz was down about -9dB from the rest. With an equalizer you could effectively increase that -9dB to 0dB so that 40Hz would be at the same level as the rest of the system is. Lots of head units have an equalizer setting. It acts as bass boost.

What size of box is your speaker in jpruden? Is it vented or sealed?

I would still suggest building the speakers into a vented box if you want the low bass punch. Or sell your two subs and get one of the 12W3s. It is -3dB down at 40Hz where as your boxes are -9dB at 40Hz. Thats a quarter of the volume of his at 40Hz.
 

jol50

Member
2007-11-08 2:14 am
For one if you want to 'feel' it, you need 20Hz or at least 30. A sealed box rolls off on the bottom there but often rock does not go that low anyway. It depends on the Q of the sub and other things, but often a sealed box will be tighter and give more punch...less thump/rumble/thunder. If you want smooth sound you want both. Your enclosure affects this more than anything, but the drivers might not be able to do what you want I did not look them up. If they roll off that much you need larger box or likely ported box to get more bottom. Lots of rolloff is SPL setup and they don't sound good most of the time.

Initially you can try what I near always end up doing with sealed and that is go to walmart and buy a bag of $2 poly stuffing. Stuff the box for each sub at least half full or 3/4 for max effect. Do not pack it down in there, do it so the sub can still breath and cool itself near magnet/VC. This should smooth it out some by lowering the response sort of like making the box larger.

Another issue you often get with small sealed is they peak hard at 100hz or whatever. What happens is if you turn the crossover up you get tons off midbass because they get very efficient up there. You cut them back and loose a lot of db because they are rolling off down low....it is not a good setup and difficult to tune. A crossover with variable slope can help as well as a parametric eq for subs. Problem is you still have a sub setup that does not want to produce low sounds like it does midbass....it does not want to do what you want it to. Everyone wants a tiny box though, and that is the way many of them work without just the right driver in them. Many low Q drivers that will often have a peaky response as well even though lower Hz response. In a hurry someone catch me if any of that is wrong.

-9db is a dead sub, you will hardly hear those frequencies at all and find it difficult to force it out of them even with an eq. It can be done with lots of power, but IMO not worth the hassle when you can go to a better setup that meets your needs unless you have serious reason not to change/mod what you have.

Note that a ported box will need to be larger.
 

Flyin11

Member
2007-09-26 1:29 pm
The only things different my headunit has other than the regular crossovers, bass, treble, balance, fader, and sub level is:

Bass

Bass Center Frequency
Bass Q Factor
Bass Extend

Middle Level has the same as above and Treble just has a Treble Frequency. That's the only other options I've never head of or messed too much with. No built in EQ. With all the other options and crossovers, and with a already subwoofer level control, I didn't think I would ever need a EQ again. Not sure if any of those would help anything. I've tried them before and it just made it sound more weird.

How big of a deal is -9DB? Doesn't sound like a lot...
 

Flyin11

Member
2007-09-26 1:29 pm
Some stats from Crutchfield on the sub:


Size - 12 -inch
Impedance - 4 ohms
Cone Material - IMPP w/metallic finish
Surround Material - Rubber
Sealed Box Volume - (cubic feet) 1.25
Ported Box Volume - (cubic feet) 1.75
Port diameter (inches) N/A
Port length (inches) N/A
Free-Air - No
Dual Voice Coil - No
Sensitivity - 86.81dB
Frequency Response - 22 - 200 Hz
RMS Power Range (Watts) 50-300
Peak Power Handling (Watts) 600
Top Mount Depth (inches) 5 1/8
Bottom Mount Depth (inches) N/A
Cutout Diameter or Length (inches) 10 7/8
Vas (liters) 105.81
Fs (Hz) 23.68
Qts 0.414
Xmax (millimeters) 9.5
 

jol50

Member
2007-11-08 2:14 am
That might be a parametric. You can try setting that low Hz and boosting, or set it high and cut it back. Change the amp gain to level subs back out to rest of system. The Q will be the width of what you cut or boost. They take a while to tune in right by ear. If you play music that makes you notice how bad the sub sounds, then turn the boost way up on a parametric and change the Q, you can hear how it boosts just what the center is at or a wider range with Q higher. Play music with lots of low and mid bass, even a bass sweep tone may help you to even it out. I have an alpine eq that works that way, but not sure what you have. I has center freq, Q for how wide, and gain level for how much you boost or cut that selection of frequencies.
 

jpruden

Member
2007-09-13 4:57 pm
Hi,

It's one of the sealed PowerWedge enclosures from JL Audio

http://mobile.jlaudio.com/products_enclosures.php?menu=9&prod_id=423

Argh... guys, you've got to realize how pronounced the bass boost is in a small car like Flyin's. In his car, an 8" sub will easily get down to 20 Hz if you include the bass boost.

My previous setup was a pair of JL Audio infinite baffle 8" subs and they could produce heaps of output right down to the low 20's on only about 100 watts. His pair of 12s should be killing him with 400 watts of power.

There's something else wrong here...

jol50, you're correct about the peak from *really* small sealed boxes (boxes tuned to a Qts of 1.2 or higher), but I think you're a bit off on the whole "low Q driver" issue... I'd expect to see much less peak from a low Q driver in any box when compared to a similar high Q driver. The Qts will determine the shape of the curve in any case.
 

jol50

Member
2007-11-08 2:14 am
Yes, low Q sure gets lower where you want to be. It is just every time I model them I see a peak, not a bad one and not awful sounding 100Hz like high Q in little box....but not a straight line either. Then again few subs have straight lines and does it really matter...likely not you are correct. My complaint is the manufacturers love to print the very smallest box they possibly can and it often does not sound that good. It will handle the most power though, if you need that.

I run 4 12s IB in a small sedan into the back seat with plenty of leakage over the seat. Think they are Qts- .49 infinitys. I like the sound, 30Hz is nothing to put out and with a parametric I can smooth them out nice so they have punch also. Only have 420wrms at 14v or whatever, so likely more like 300-350 real rms on all four. It is really not enough the subs don't move that much wot, but can't get the rest of the system to keep up with them anyway until I do some more work on it. It is not near as loud outside the car like most boxes are. It can sound like a HT inside though and shake the whole car.

I agree, 400w on two 12s should be pounding. I can feel my 12s on that power if I crank them up...but then I can't hear the music. My plan is actually to go to lighter 12s or two 15s to cut weight. Four of these weigh a ton and if I don't need all that why have it.
 

shagone

Member
2007-04-11 9:42 pm
Flyin11

What are you using up front? if i remember correctly it was stock speakers? if you listen to rock then you should really invest in a nice set of component speakers up front with a solid midbass of at least 6.5". this will pull the bass up front and allow you to feel the smack of the kick-drum that you are missing that is between 60-100 hz as noted above. the component set should be given ample power from an outboard amplifier if you expect them to blend well with the subs. Without this the bass will never feel just right.

bass without solid mids and highs to match it sounds like poo in most all cases yet people run subs without upgrading the rest of factory sytem all the time. they just don't know what they are missing. in my last temporary car (89 maxima beater) people would always ask me how i got all the bass up front yet all i had in there were eclipse point source 4" in the doors angled up a bit with mdf spacers and one 10" xtant a-series sub with 2 xtant amps in the trunk. the thing was, i was feeding them plenty of clean power and i had my settings tweaked so it all blended in nicely and gave the apperance of up front bass without drawing your ear to where the sub was located in the trunk. it was plenty loud and clean too.:D too bad i sold all the gear with the car for $1,000
oh well.