Why does my sub sound like crap?

[mahabali]

Hi all. I picked up a JL Stealthbox and JL 250/1 amp off of the classifieds on this board.

I hooked everything up yesterday and it sounds like absolute crap.

The sub is a JL 10w3v2. I am running the Scion Pioneer T1809 head unit.

I have installed many systems in many cars over the years so this isnt my first rodeo... But I am nowhere near an expert. Ok on to the install.

I put the amp under the passenger seat... Ran 8 guage power wire with a 50A fuse. I grounded the amp under one of the passenger seat bolts. (removed seat for the install) I ran the lead to switched power and the RCA cables to the HU. The amp powers up fine and appears to be working correctly.

before I mounted the stealthbox I tested it and it did NOT sound good. really rattly bass. Not clean just crappy bass and I am not even playing it lound. I tuned the amp to JLs specs for the Stealthbox and played with the gain. I even turned the sub control on the Headunit to -6 and adjusted the gain. I just cant get the sub to sound good. It sounds decent at very low volume but like crap with even moderate volume.

I pulled the sub out of the box and there is no visible damage to the sub. Its dual voice coil and I have it wired in series. I have the Positive wire from the box going to the positive on one voice coil and the negative from the box going to the negative on the other voice coil. Then I have the negative from the positive side conected to the positive from the negative side on the sub.

Any ideas? does it sound like the sub is blown? Bad amp? Bad wiring? I am about ready to just pull the whole thing out of my 4runner. Thanks!

 

[borgzman]

Maybe your speaker/subwoofer is "out of phase".

To determine, adjust the balance control to the Left only, or Right only. If adjusted to the Left, The Left channel amp will have audio output to the Left speakers(and subwoofers) only. In that setting, observe if you'll hear a clean Bass.
Then set the balance to the Middle, it would mean that both Right and Left amp will have outputs to both Right and left speakers(and subwoofer). If you hear that "rattly bass" then your speakers/subwoofer is "Out of Phase".
If those above are observed, try reversing the connection in one of the speaker's teminal in the either Left or Right channel. So + will be connected to - , or red will be conneted to black.
Do it only in either Channel(L or R) speakers/woofer..Reversing both channel speakers will go back to "out phase".


Google search Out phase Speakers :
out phase speakers - Google Search

 

[mahabali]

Thanks I will try that tonight.

If I had another Sub/box I would hook it up to the amp to rule out the amp being bad and then I would know it was the sub.

 

[810moto]

take it back.

 

[riceandpho]

whats the voice coil on the sub itself? the w3v2 are mostly d2 d4 d6, test the sub on another amp, maybe the jl amp u got is bad, reason is if the sound is all distorted it might be the gain setting, if thats not it , its the amp, something internal is blow, i would noe since one of my amp had the same problem, it overheated and sound was distorted, and all my wires are new and no cuts, this is why u dont buy the amp used, lucky i only bought the 300/2 for 100 bucks off craigslist.

 

[riceandpho]

also maybe the subs was abused, so u might as well upgrade that to a w6v2 if money is no problem to u.

 

[nightshade000]

I have the Positive wire from the box going to the positive on one voice coil and the negative from the box going to the negative on the other voice coil. Then I have the negative from the positive side conected to the positive from the negative side on the sub.

You could be under-powering the sub. This can make subs sound like crap. In the wiring configuration you described, assuming each voice coil is 4ohm, you're running at 8ohms. On paper, this means half the power, RMS, than the amp is capable of putting out.

JL makes awesome amp. If your amp is rated at 250w RMS at 4ohm, then you're running at 125w RMS right now, which is under powered for most of JL's stuff.

JL makes great products, and their amps should be 2ohm stable. (This is all assuming your sub is 4ohm each voice coil) I would run positive from the box
terminal to the positive of one voice coil, then another wire from that positive to the other voice's positive. Same with negative, but for the negative terminal, of course).

Of course, your stuff may have been abused, and then you're SOL unless you got something like a squaretrade warranty.

 

[drmorbius]

Hi all. I picked up a JL Stealthbox and JL 250/1 amp off of the classifieds on this board.

I hooked everything up yesterday and it sounds like absolute crap.

The sub is a JL 10w3v2. I am running the Scion Pioneer T1809 head unit.

I have installed many systems in many cars over the years so this isnt my first rodeo... But I am nowhere near an expert. Ok on to the install.

I put the amp under the passenger seat... Ran 8 guage power wire with a 50A fuse. I grounded the amp under one of the passenger seat bolts. (removed seat for the install) I ran the lead to switched power and the RCA cables to the HU. The amp powers up fine and appears to be working correctly.

before I mounted the stealthbox I tested it and it did NOT sound good. really rattly bass. Not clean just crappy bass and I am not even playing it lound. I tuned the amp to JLs specs for the Stealthbox and played with the gain. I even turned the sub control on the Headunit to -6 and adjusted the gain. I just cant get the sub to sound good. It sounds decent at very low volume but like crap with even moderate volume.

I pulled the sub out of the box and there is no visible damage to the sub. Its dual voice coil and I have it wired in series. I have the Positive wire from the box going to the positive on one voice coil and the negative from the box going to the negative on the other voice coil. Then I have the negative from the positive side conected to the positive from the negative side on the sub.

Any ideas? does it sound like the sub is blown? Bad amp? Bad wiring? I am about ready to just pull the whole thing out of my 4runner. Thanks!

Each voice coil must use one amp output lets say the first one is left channel, then hook up the left channel out positive to positive and negative to negative. Hook up the other voice coil to the right channel exactly the same way, that is positive out to voice coil #2 positive and negative out to voice coil #2 negative. If you reverse one of these coils polarity wise it will sound like the speaker is trying to tear itself apart which is exactly what it is doing!

 

[nightshade000]

Each voice coil must use one amp output lets say the first one is left channel, then hook up the left channel out positive to positive and negative to negative. Hook up the other voice coil to the right channel exactly the same way, that is positive out to voice coil #2 positive and negative out to voice coil #2 negative. If you reverse one of these coils polarity wise it will sound like the speaker is trying to tear itself apart which is exactly what it is doing!

He stated he has a mono amp. No left/right channels.

 

[kimboy]

Do you have a quality hi-low output converter? I'll buy the JL stealthbox if it doesn't meet your expectations.