[Jstaguy24]

I have 2 15" powerbass 2xl-15d4 subs. Right now I have one installed in 4.75 cubic feet. Specs are 4.5 from powerbass. It is tuned between 27 and 28 hz. The sound is great, it hits low and hard. Problem is I listen to a lot of rock music. I am getting very little sub output in a lot of my rock music. I played some test tones tonight off of
Spotify.
30 hz is loud, shakes the hell out of the car
40 hz, a bit louder shakes the hell out of everything
50 hz slightly less volume but still loud and shakes everything
60 hz very low volume and output in comparison.
Then it jumps to 100 which is pretty much nothing due to crossover
I think a lot of my rock music is falling in that 60-100 hz range and it's seriously lacking. Will a higher port tuning help? I Can easily change port length. Im going to build a box for both subs. I just want to get this figured out before I do..

 

[gijoe]

How are you measuring this? Most rock music (that is, using real instruments) will only drop down to around 40Hz, if you are getting loudest at 30Hz with tones, I'm thinking a lot of the output at 30Hz is clipping and distortion.

Have you modeled that enclosure and sub to see what kind of response you should be getting? If 30Hz is that much louder than 60Hz I suspect something is terribly off.

 

[Jstaguy24]

30 hz isn't nearly as loud as 40 hz but it is louder then 60 hz. I'm just listening to test tones and listening to the difference. I have not modeled it. Not sure how to go about that

 

[gijoe]

A free RTA app for your phone will give a reasonable idea. You can download WinISD to get a better idea by plugging in the woofer and enclosure specs.

For your style of music you ideally want a good response down to 40Hz, you don't really need anything below that. Now, there are plenty of ways to get good response below that, but in your case you may want to consider whether or not you are willing to sacrifice 40-100hz output for 20-40Hz output that most of your music doesn't contain.

 

[miniSQ]

How are you crossing the sub? What slope and frequency?

 

[Jstaguy24]

It's crossed from amp. Between 80-100 hz. Couldn't tell you the slope. I Would have to see what the audiopipe ap1800.d specs are. I listen to 90% rock. If I pull up some dubstep or bass nectar on spotify it sounds great and hits hard and low. But lacking for rock which is my primary music. Would sealed be a better option for My needs? Or I can try different port lengths

 

[Jstaguy24]

A free RTA app for your phone will give a reasonable idea. You can download WinISD to get a better idea by plugging in the woofer and enclosure specs.

For your style of music you ideally want a good response down to 40Hz, you don't really need anything below that. Now, there are plenty of ways to get good response below that, but in your case you may want to consider whether or not you are willing to sacrifice 40-100hz output for 20-40Hz output that most of your music doesn't contain.

I moved and computer is in storage. I don't have access to do any type of modeling at the moment. I want it to sound good on rock. So if that means different port tuning, sealed box, whatever I'm open to it

 

[Brian Steele]

I think to achieve what you want to do, you need to cut the output below 60 Hz a bit.

A few ways:

1. EQ it out if you can (but you still end up with that big box)
2. Block the vent (but you still end up with that big box)
3. Use a small sealed box instead.

In your case, I'd be tempted to just build a small sealed box for testing. Design for a Qb of between 0.9 to 1.0. And design it with flexibility in mind, so you can try it out in different positions in the trunk of your vehicle to identify the best location for the subwoofer.

 

[Jstaguy24]

I don't have eq ability yet. May be purchasing a dsp this week. I could try the pair of subs in the big box sealed. Just have to cut a second hole. The subs are recommended for a 2.5 cubic foot sealed box I believe. Will have to check the manual again as the optimum enclosure. It's in a suburban. So no trunk. Right now sub is facing up, ports out the back. Only problem trying 2 sealed in this box would be they can't be on the same side of box. It's basically a 24" square

 

[syc0path]

Open the hatch and listen to the freq response again. U could be getting cancellation due to sound wave reflections.

Ports and subs should generally be facing the same direction, and a cube is 1 of the worst shapes for box if u want flat freq response. So the box should be rebuilt anyway. I would make it smaller to drive the freq response higher. A sealed box is certainly ezr to model and build, but I think it would be worth the time to model a smaller ported box.

 

[thehatedguy]

The shape of the box for a subwoofer really does not matter, not for a car and the size of enclosures we have in them.

 

[Jstaguy24]

I will be ordering my 8" midwoofers for my front stage and a mini dsp today. So that may help eliminate some of the 60 hz and up issues anyway. I do plan on doing a complete Box rebuild for 2 subs instead of 1. Just figuring out the best path to take when I do it. If I go sealed, it will be easier to keep my 3rd row seat functional. Might be harder if I go ported. But getting my system sounding the way I want it is more important then keeping my 3rd row seat that may be used once a year

 

[syc0path]

The shape of the box for a subwoofer really does not matter, not for a car and the size of enclosures we have in them.

In theory the wavelengths are too long to fit inside the enclosure. In reality, the waves bounce back and forth inside the box until they travel the distance of a wavelength, and then u get interference. So yes, the size, shape, and position of the box do have an effect on freq response.

 

[thehatedguy]

There are no waves to bounce around to do that.

 

[ATOMICTECH62]

Get an Epicenter or Epic 160/150.

Im an old fart and listen to lots of 60's,70's and 80's rock.Some of that stuff has zero bass.
Judas Priest and Motley Crue are some of the worst offenders.At least the earlier recordings are.A lot of their bass is around 70-120hz and asking 6.5" or 8" to belt out those frequencies at the same levels of output you get from 12's is unfair.
The Epic 160 has a circuit that divides the original signal by 2 so 70hz is now 35hz,80hz is 40hz,etc....
These Audio Control pieces will not work with Rap or other Bass heavy material since it drops the low frequencies to ultra lows and there is a 20-25hz HP filter in the circuit.It actually removes bass from that type of music and what does get through is a muddy mess.This is why not many people use them.They are useless on newer material.
But when switched on they can produce tremendous amounts of bass.I never turn it past 50%.It can take music with no bass and give it gut retching output.More then any Rap music Ive heard.
Its not the most accurate thing but for about $100 its a must have piece for old rock.Plus it has a digital volt and SPL meter built in.

http://www.crutchfield.com/S-jUYk48K8rHJ/p_161EPIC160/AudioControl-EPIC-160.html

 

[HertzGuy]

A totally Uneducated Opinion but from a Bass Lover none-the-less, I think for your style of music a 15 just isn't really suited to it. You may, although I understand you probably just plopped down a bunch of money on them, but you may want to sell/trade your current 15's for some 12's or 10's. I have always found that 10's sound "Best" if you listen to Rock music. They have that quick punchy Bass that you just can't get from a 15. Plus, you don't "usually" tune a 10 as low as you do 15's (or maybe a better way to say it, is that you normally crossover a 10 "Higher" than you would/do a 15) therefore your 10 would play more of that Upper Bass that Rock music usually finds itself.

My girlfriend has 2 10s that I put in her trunk, she listens to pop and Country but mostly Rock and it sounds really good in her car. Play that same music on my 15 and its TOTALLY different!

But also, throwing in those 8in mids might pick up a lot of that slack from your 15s.
Or, maybe swapping your subs for a different size might help, but also since your in a Suburban that is a lot of air you're going to have to pressurize with Bass so...

 

[Jstaguy24]

The subs sounds great, very musical on anything I listen to as long as it's in the lower frequency range. I just figured out by listens in gto test tones that it fell off quickly at 60 hz. If I can just get them to do the same up to around 80-90 hz I would be ecstatic

 

[thehatedguy]

I dunno...I have used 15s for the last decade and I listen to a lot of death metal, and they have never let me down.

 

[gijoe]

A totally Uneducated Opinion but from a Bass Lover none-the-less, I think for your style of music a 15 just isn't really suited to it. You may, although I understand you probably just plopped down a bunch of money on them, but you may want to sell/trade your current 15's for some 12's or 10's. I have always found that 10's sound "Best" if you listen to Rock music. They have that quick punchy Bass that you just can't get from a 15. Plus, you don't "usually" tune a 10 as low as you do 15's (or maybe a better way to say it, is that you normally crossover a 10 "Higher" than you would/do a 15) therefore your 10 would play more of that Upper Bass that Rock music usually finds itself.

My girlfriend has 2 10s that I put in her trunk, she listens to pop and Country but mostly Rock and it sounds really good in her car. Play that same music on my 15 and its TOTALLY different!

But also, throwing in those 8in mids might pick up a lot of that slack from your 15s.
Or, maybe swapping your subs for a different size might help, but also since your in a Suburban that is a lot of air you're going to have to pressurize with Bass so...

This is nonsense and bad advice. It's been beaten to death, but a bigger woofer is not inherently slower than a smaller woofer. You don't get punchy bass from 10"s and deep bass from 15"s.

Please don't get rid of your 15"s because you think they won't sound good for rock music.

 

[mmiller]

Really, do we really have to go here?? You're flat out WRONG!! Ill use a 15 or 18 anyday of the week over a 10, for any type of music. You re having issues with enclosure sizes/xover points/Tuning/Ect if you feel otherwise.

QUOTE=HertzGuy;2211860]A totally Uneducated Opinion but from a Bass Lover none-the-less, I think for your style of music a 15 just isn't really suited to it. You may, although I understand you probably just plopped down a bunch of money on them, but you may want to sell/trade your current 15's for some 12's or 10's. I have always found that 10's sound "Best" if you listen to Rock music. They have that quick punchy Bass that you just can't get from a 15. Plus, you don't "usually" tune a 10 as low as you do 15's (or maybe a better way to say it, is that you normally crossover a 10 "Higher" than you would/do a 15) therefore your 10 would play more of that Upper Bass that Rock music usually finds itself.

My girlfriend has 2 10s that I put in her trunk, she listens to pop and Country but mostly Rock and it sounds really good in her car. Play that same music on my 15 and its TOTALLY different!

But also, throwing in those 8in mids might pick up a lot of that slack from your 15s.
Or, maybe swapping your subs for a different size might help, but also since your in a Suburban that is a lot of air you're going to have to pressurize with Bass so...[/QUOTE]