Can't tell if my subs are blown, need some help

[d_tek]

Hey guys, I'm wondering if you are able to tell whether the issue, as seen in the video, is with my subs or my amp. The subs play fine at a low volume, but once it reaches a certain threshold then it starts to have an issue. You can hear it at the beginning of the video and then again at around the 45 second mark. I appreciate all feedback, thank you.

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[audiobaun 5,000+ posts]

Id pull each sub and check them with an DMM for the acceptable ohm load for each sub since you have easy access to do so. While you are there.. Check for any leaks within the enclosure inside. Check to make sure that each sub has a secure connection as well as at the amplifier. Check RCAs make sure secure and not Kinked. Check all Power and Ground connections on that amplifier and the remote also so that you have a solid exposed wiring connection at the amplifier. Check the power supply connections and grounds for non-corrosive wiring. Clean any corrosion of any wiring connections.
These are a few things Id start with to find the Culprit.
There may be a possibility that you are reaching the limitations of the sub at a Htz level as well?
Another to be considered is the Recording of the music and method being used/source.
Just a couple things to be considered as well.
Let us know what you find. Others may be having similar issues as well ,and your findings to resolve the issue will help others.
SYSTEM, COMPONENTS AND VEHICLE INFORMATION NEEDED
What Type of Vehicle do you have ? Stock Battery,AGM? Stock Alternator? Size power wiring?
Model and make of HU?Amplifiers? Sub woofers?External fuses,Distro Blocks? Size of Ground wiring?Has the Big 3 been done?

 

[hispls 5,000+ posts]

Generally if the subs were broken they would be giving you trouble at every power level.. There's something else going wrong here. Do please give us more details on amp, subs (impedance you're running), and electrical system. Are you confident that there are no wires shorting anywhere? How is your gain adjusted?

 

[MattinMO]

Sounds like your bottoming them out.

 

[Buck 5,000+ posts]

That sounds to me like too low of ohms on the subs and the amp is going in and out of protect or something.

 

[Buck 5,000+ posts]

That sounds to me like too low of ohms on the subs and the amp is going in and out of protect or something.

OP you need to get a DMM if you're in car audio. It's the most useful tool you can get, you can buy one for $20. You need to read what ohms your subs are wired to, in my opnion. I could be wrong, but you'll still need to start reading stuff until you figure it out.

 

[Buck 5,000+ posts]

That sounds to me like too low of ohms on the subs and the amp is going in and out of protect or something.

Look and see if you have a red light that comes on on your amp where it's going into protect when this happens.

 

[d_tek]

the amp is decently old so it doesn't have a protect mode indicator
the issue started when I was playing some music that had a bass line that is much higher than it should be (my buddy mixes his music without a sub, so I think he cranks the bass up because he can't tell how much there actually is)
the amp has played literally 10x louder than what is in the video with no problems and given that it still works at low volumes I really can't tell what the exact issue is. From my knowledge it obviously is the subs or amp, and the subs can still go as loud as they could before the issue started but it is only for maybe .5-1.5 seconds before the issue kicks in again
I'm on a stock alternator and my 4 channel amp sometimes will kick off when I can tell I'm at a lower voltage but my subs amp has never done this before so I'm not sure why it would begin to do so.
I'm gonna check out the impedance of the subs in a little bit so I'll let you guys know what I find

 

[dragon.breath 10+ year member]

I have seen a similar problem before. The problem in my case was a bad subwoofer. The voice coil had a bad spot in it. When it was cold it would make contact and play normally. When the coil started heating up it would start losing connection.

 

[d_tek]

just tested it with a DMM, one sub read 4 ohms and the other read 3.6. What do you guys think?

 

[jt4x4]

I'd start with listening to less shitty music and see if that helps.

If you push on the cones do you feel any friction or hear any crunching?

I think they sound blown, but tough to tell from a video.

 

[d_tek]

I'd start with listening to less shitty music and see if that helps.

If you push on the cones do you feel any friction or hear any crunching?

I think they sound blown, but tough to tell from a video.

They sound fine when pushing down on them, or at least sound the same as before the problem started

 

[jt4x4]

And they are in the same enclosure as before the problem? That essentially rules out the box.

Did you adjust any settings on the amp recently?

Did ANYTHING change before your issue arose? Doesn't matter how insignificant it might seem. If you didn't change anything, then something broke.

Measure voltage at the speaker terminals of your amp to get an idea of how much power your subs are getting. That'll tell you if you are overpowering them.

You could try hooking them up one at a time to see if the noise is isolated to just one sub.

An oscilloscope would help, but I know most people don't have access to one or know how to use one. Any chance you are the minority who does?

 

[d_tek]

And they are in the same enclosure as before the problem? That essentially rules out the box.

Did you adjust any settings on the amp recently?

Did ANYTHING change before your issue arose? Doesn't matter how insignificant it might seem. If you didn't change anything, then something broke.

Measure voltage at the speaker terminals of your amp to get an idea of how much power your subs are getting. That'll tell you if you are overpowering them.

You could try hooking them up one at a time to see if the noise is isolated to just one sub.

An oscilloscope would help, but I know most people don't have access to one or know how to use one. Any chance you are the minority who does?

really the only change between before the issue and after the issue is that I updated spotify. I use an EQ on there so maybe they changed the dB level of it after the update. Should've mentioned this though, I was listening to my buddy's music when the issue happened and he doesn't have a sub to mix with so on some of his tracks he cranks the bass line way up, which paired with two EQs is my guess of the root of the problem.
I know the subs are underpowered, if anything, because the amp's max output is 600 watts and it does 300RMS maybe (can't find a definitive answer for that, but the amp is a kenwood KAC-6104D; https://www.crutchfield.com/S-uT22BIYnFPV/p_113KAC6104/Kenwood-KAC-6104D.html). The subs themselves are crunch gtr12s4's and they have an RMS of 350 watts a piece
Unfortunately I don't have an oscilloscope, but I'll try out one sub at a time, from what I can hear (and see) it is both of them having an issue though

 

[dragon.breath 10+ year member]

Definitely try the subs one at a time. They are wired together, so if one sub is shorting out....