Subs overpowered? Too much?

[manooti]

Before we begin, please dont flame me for being a budgeteer //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

Installed Power Acoustik Gothic 4500d (dont say it lol) and 2 NVX NVS124 subs (dual coil 4 ohm, 350rms) in sealed box. I think the brand of box was bass(something)..

PA says amp does 2700x1@1ohm. I know its probably not near that at all, but one can only hope lol. I'm guessing it does around 1500 with the 120A fusing. Anyway, I was expecting it to sound less than what it is it which is a plus given the price to performance ratio.

Using 0GA cabling from front to back and ground as well.

Now, the gain issue and maybe distortion.

I used the DMM method to adjust gains for 1ohm@ 1200rms for the subs. I do think it might be overpowering too much.

Gain is close to half way mark with SSF off, LPF to max, BB off, and with tone of 49hz@ -5db 3/4 max volume on Pioneer deck with 2v outputs. Subout set to max for tuning.

DMM VAC@ 34 steady if that means anything

When I play music there is crazy rattling going on. I'm not sure if it is the subs being overpowered while not being broken in yet or my panels that I ended up dropping the clips inside the frame of car //content.invisioncic.com/y282845/emoticons/rage.gif.0ad8a6e5565b5fddce406566fdd05149.gif

Forgot to mention, with Loudness off on radio I had almost no bass. Had to turn everything up after tuning, so I enabled Loudness to retune with DMM. Sounds good except for whats stated. FWIW it does sound pretty aewsome and the weird sounds are not the sub bottoming out. Had an L7 clip and bottom out to kingdom come till the leads ripped off and made scratching noises so I know what it would sound like.

I want to try tuning with DMM and ear at same time, but neighbors dont like me already.. reason unknown.

What do you guys think I should do? No strange scent yet. Maybe box is wrong, maybe subs ****, maybe amp? Amp stayed cool at max volume too as a side note.

Sorry for the thesis.

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[hispls 5,000+ posts]

Garbage in, garbage out. Clearly something is malfunctioning or you are pushing it beyond it's limits. If you have anything else to test with through a process of elimination you may be able to figure it out, but way too many variables from your vague description of the trouble.

 

[Jeffdachef 5,000+ posts]

Go to an unpopulated area when you have free time, see if its an air leak in the box, the box is falling apart, hold down any panel or pieces of metal in the car, find out and pinpoint your rattle and we'll go from there. Right now you just say there's a rattle... Normally you can pinpoint the rattle pretty darn easily and you will know if your subs are bottoming out or not.

If you can determine the sound is from your subs, it might be ripped spiders so you might have to take your subs out and play them free air and check the spiders for damage.

 

[manooti]

Garbage in, garbage out. Clearly something is malfunctioning or you are pushing it beyond it's limits. If you have anything else to test with through a process of elimination you may be able to figure it out, but way too many variables from your vague description of the trouble.

It's just rattling that makes me thinks its distortion, but not 100% certain. Never had low powered subs like these so not sure.

Go to an unpopulated area when you have free time, see if its an air leak in the box, the box is falling apart, hold down any panel or pieces of metal in the car, find out and pinpoint your rattle and we'll go from there. Right now you just say there's a rattle... Normally you can pinpoint the rattle pretty darn easily and you will know if your subs are bottoming out or not.
If you can determine the sound is from your subs, it might be ripped spiders so you might have to take your subs out and play them free air and check the spiders for damage.

Thanks, man. Checked the subs, theyre still good. I'll have to go to a dead area and test the box. The box is really old and used years ago in my kicker setup. Maybe it went loose where I cant see it.

What do you think about the Loudness on head unit making the bass come alive to almost double? Had to turn loudness on and set gain from there.

I was just messin around in WINISD. No idea about how to use it yet but a few youtube videos in and I'm itching to go to home depot lol. Maybe build a brand new box... 6th order bandpass tempting

The song Bass I love you, known for the lows, plays ******. It's when the higher frequency bass hits is when the rattle comes in. Low frequency is good. Nice quiet butt jiggler. Low frequency would reveal clipping/distortion or sub damage easier, right? So if my high frequency bass hits and rattles its not mechanical and maybe box, box design or car?

 

[hispls 5,000+ posts]

OP. You have very dubious quality subs, amp, and box, are using "bass boost" on the head unit, and something is making a rattling sound. At this point you can rule out nothing, but I'd suspect the box coming apart at the seems or the subwoofers being overpowered or failing mechanically first.

If you don't have the budget for proper equipment I'm quite confident you don't have the budget to build and test enough boxes to make a bandpass box come out with acceptable results.

 

[manooti]

I'm a former contractor by trade and have the tools. I doubt the MDF is that expensive in relation to electro ic equipment. Anyway that bandpass i was referencing would definitely blow subs.

Also checked box a few minutes ago. It is leaking air and the terminal cup was loose.

 

[CrossoverOre 10+ year member]

if the box is several years old that would be the first thing I check.