Question for those of you that have experience with 15 inch subs...

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scjmc

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I recently installed a single kicker CVR 15" dual 2 ohm VC sub into my car. I did this to regain some trunk space that the 2 12" Kenwood subs were taking up. Despite pushing twice the power to that sub I am very unimpressed. I have only ever used 12s and 10s. Someone please tell me if this is how 15s react. At certian HZ levels say 30-50 the sub pounds. At any other level it sucks. It also puts out very little bass in the lower volume levels where the 12s would still react. Sounds like I have the factory subs only. The speaker is rated for 25-250HZ, but it REALLY favors a small frequency range. Songs that have good bass, but not very deep bass sound like I have factory subs only. I have installed many systems and I know what I am doing though I am no professional. I use high quality wiring (2GA), 1.5 Farad cap, correct box volume, etc. I have the impedance correct, and the polarity of the voice coils. What it all boils down to is the 12 inch subs I have used in the past put out good bass in whatever range or volume I set the crossover to. The 15 only puts out bass (and ots of it) in a very specific range. I have swapped the 12s back in and I get good bass range again. I even put the 15 in my wife's Altima (thank God she likes driving it) and I get the same wierd specific bass issues. I want to know is it the kicker sub that is like this, or do the larger subs react this differantly? Sorry for the long post...
 
Do you have a bass boost knob? I didn't plug mine in when I first hooked mine up and there was like nothing (stock stuff).. But when I pluged it in and turned it up it popped out one of my tails.. :lol:

It was missing the little nuts and I replaced.. :)
 
Finally! A question i know alot about:dancefool {<-- Kinda gay i kno}
Any way..
Sounds like u have the freq on ur crossover set to low is it a standalone crossover or is it built in ur amp?.. either way bring it up to about 110 hz.. Also.. how are u wired up? 1 or 2 ohm? if ur amp is 1 ohm stable then u shuld drop it in 1 instead of 2.. thats double the power right there.. also is it bridged? sub wired up parallel? is the box ported? if not then thats gonna be a big problem right there.. as sloppy as 15's are they perform best in a ported box.
 
^^^

No bass boost and gain set to 0 or turned up slightly is how i roll.
 
StackZzz LS said:
Bass boost adds nothing but distortion. if u have to use a "bass boost" then its not wired correctly or there is not ample power to run the subs. :cool:
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Sorry.. I looked at it and it's like a volume control.. Never seen an amp with one but this one is crap.. So I am going to get a new one sometime..
 
Ohh.. And to add, make sure the output (if your using RCAs) is turned up.. I have a place to turn up/down the output volume on the deck..
 
Thanks for the responses. The sub is a dual 2 ohm VC sub. It has 500W RMS rating (250 per VC). My amp puts out 300W X2 RMS @2 OHM. It is not 1 OHM stable. I have played with the crossover setting alot. I started at 80HZ and slowly moved it up and it is now at 200HZ. It does not seem to make a differance. My deck does not have an option to change the preamp level, so I played with the crossover (it is on the amp itself), and the gain. I normally run the 12s with the gain slightly up from 0. With the 15 I have the gain jacked way up and the bass boost knob st full tilt. I know this is not the correct way to set it up, but I am trying differant things. The sub is in a sealed box because the ported box volume is too large.
 
What is the volume of your box? Too small of a box can lessen a subs impact. Also if it's a brand new sub it will need some break in time for maximum effect.
 
Can you return the sub??

If not happy with it i would try and get my money back.
 
FASTLLS said:
Ohh.. And to add, make sure the output (if your using RCAs) is turned up.. I have a place to turn up/down the output volume on the deck..
Click to expand...

All that does is add distortion also.. Yes, it adds volume but it also distorts the signal.

scjmc said:
My amp puts out 300W X2 RMS @2 OHM. It is not 1 OHM stable. I have played with the crossover setting alot. I started at 80HZ and slowly moved it up and it is now at 200HZ. It does not seem to make a differance. The sub is in a sealed box because the ported box volume is too large.
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Try Bridging the amp since your only running 1 sub u can just push the 600 watts to the sub instead of sending the power in two channels. Big Difference in output. Also.. 15's dont perform well in sealed enclosures unless you have high end subs and your running at least a 1000 watts to them.. Oh and one 15 will not move as much air as two 12's.. so u have to factor that in also. If i were u i wuld probably return the sub and get a cpl 10s.. You'll have more usuable bass range that your looking for.

BlackLS06 said:
Can you return the sub??

If not happy with it i would try and get my money back.
Click to expand...

+1
 
FASTLLS said:
Sorry.. I looked at it and it's like a volume control.. Never seen an amp with one but this one is crap.. So I am going to get a new one sometime..
Click to expand...

Is it an epic centre? looks kinda like a telephone wire that u can mount inside the cabin of the car..
 
StackZzz LS said:
Also.. 15's dont perform well in sealed enclosures unless you have high end subs and your running at least a 1000 watts to them..
Click to expand...

That is entirely untrue. depending on the T/S parameters 15's can perform perfectly fine sealed, as can any sized sub, so long as the box is the appropriate size. The amount of power being run to a sub does not mean it is better for sealed or ported.

to the OP, you have the signs of a box that is too small. Kicker recommends no less than 2 cubic feet but as much as 5 cubic feet for this sub. I would try a box around 3.5 cubic feet and see if you get any better results. and make sure that box is airtight!
 
15's can put out a serious amount of bass but it will be in a very narrow, very low range. for them to sound good, the box has to be tuned just right, and even then it might not sound great with the wrong type of music.

bottom line, if you dont only listen to music with a seriously low bass line, a 15" is not for you.
 
MaddShadez said:
That is entirely untrue. depending on the T/S parameters 15's can perform perfectly fine sealed, as can any sized sub, so long as the box is the appropriate size. The amount of power being run to a sub does not mean it is better for sealed or ported.
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:bsflag: Imo.. 15's dont sound well in sealed enclosures because the freq range is too tight for them.. .. Thats why i said they perform better in a ported box. and the amount of power does come into play if he's on a budget. A Ported box will give him roughly 3 to 6 db gain over a sealed enclosure.. So if he's underpowering his sub it WILL sound better in a ported box.
 
1loudls said:
15's can put out a serious amount of bass but it will be in a very narrow, very low range. For them to sound good, the box has to be tuned just right, and even then it might not sound great with the wrong type of music.

Bottom line, if you dont only listen to music with a seriously low bass line, a 15" is not for you.
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+1 :Beer
 
So much misinformation in this thread. Sub size doesn't have in affect in how low it will play. Seriously? Box tuning has everything to do with how low a sub plays. Also StackZzz I though you knew about this stuff?? 15's will fine just as good as a 12's, 10's in a sealed box. Once again, the QTS, and Vas of the sub play more of a role in this.

MaddShadez seems to be the only person in here that actually knows what they are talking about when it comes to audio.

OP if it 30-50hz range is just about every rap song's bassline out there. Set your LPF to 80, and if its not hitting low enough try adding some polyfill, to your sealed enclosure. Rule of them about a pound of polyfill for ever net. cube.
 
OBI said:
So much misinformation in this thread. Sub size doesn't have in affect in how low it will play. Seriously? Box tuning has everything to do with how low a sub plays. Also StackZzz I though you knew about this stuff?? 15's will fine just as good as a 12's, 10's in a sealed box. Once again, the QTS, and Vas of the sub play more of a role in this.

MaddShadez seems to be the only person in here that actually knows what they are talking about when it comes to audio.

OP if it 30-50hz range is just about every rap song's bassline out there. Set your LPF to 80, and if its not hitting low enough try adding some polyfill, to your sealed enclosure. Rule of them about a pound of polyfill for ever net. cube.
Click to expand...

If you wuld have taken the time to read his post you wuldve read that he stated that his subs only hit hard in the lower freq and he is using the correct box volume size. And sub size has alot to do with how well they hit individual frequency's. The larger the sub the more air it will move so obviously 15's will hit alot stronger in the bottom frequency's than a set of 10's for example. and let me be clear.. im NOT sayin the 10's wont hit the same freq.. im saying they wont be able to hit it as hard. and ur also wrong about rap music mostly being in the 30 - 50 hz range.. its more like 60-125. And also.. i NEVER stated they wuldnt be fine in a sealed box. I said They Perform BETTER in a ported box imo. So Dont try and pull my card when u didnt even read the :q:q:q:qing question and responses. Hell what would i kno.. i only been installing the :q:q:q:q for over 10 ys.. And why do i have the feeling that you and shadez is the same damn person.. o well. Ur both Wrong. Putting polyfill in his damn box will not solve his problem. And to think u started ur "Reply" with "So much misinformation" wow.
 
am i missing something or did he say he has a dual 2ohm 15 and an amp that gets power at 2 ohms? if thats the case he needs either a new sub or a new amp. dual 2 wired in parallel will yield a 1ohm load which might cook an amp built to handle 2ohms min. get a dual 1ohm or a dual 4ohm sub to match the amp or a 1ohm stable amp to match the sub. i hope im not repeating anyone here.
 
themiz69 said:
am i missing something or did he say he has a dual 2ohm 15 and an amp that gets power at 2 ohms? if thats the case he needs either a new sub or a new amp. dual 2 wired in parallel will yield a 1ohm load which might cook an amp built to handle 2ohms min. get a dual 1ohm or a dual 4ohm sub to match the amp or a 1ohm stable amp to match the sub. i hope im not repeating anyone here.
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I asked if his amp was 1 ohm stable and he replied no.. so thats why i said take em back and get a set of 10's that'll perform better in the freq range he wants with the power he can provide. Glad to see someone actually paying attention. :cool:
 
thats why i asked. i provided the important info that no one else even talked about. just trying to help this guy get to the bottom of why his gear wasnt performing like it should. by the way the 15" has more of a range(lower) than the 10's and has more cone area which means it will go deeper and louder. just sayin
 
themiz69 said:
thats why i asked. i provided the important info that no one else even talked about. just trying to help this guy get to the bottom of why his gear wasnt performing like it should.
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Me too.. but u got these Know it all ass people on here that dont even read the question and answers fully. Props to u for helping tho. Thats all i was trying to do also. :Beer
 
SPL(output)---->Ported is King.
tuning has SOMETHING to do with how low a sub will play. a 10 will NEVER audibly go as low as a comparable 15 will no matter how u tune it of stuff it lol. notice i said audibly, and the reason for that is that it MAY be able to reproduce the frequency but we(humans) would not know it. fair enough?
 
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