What's wrong with this sub? (Videos included)

[aarunt1 10+ year member]

I just recently bought this sub used. I noticed it started making this annoying noise on certain tracks so I took it out the box to investigate. Here are a couple vids of it on a track that gets it to make a really annoying sound. It still bumps loud so I'm confused what is making this noise so maybe you guys will have a better idea. It is rated at 1000W RMS and has 2 ohm DVCs. My amp is rated at 1200W RMS at 1 or 2 ohms so I set my gain using this equation: Voltage of the output = sqrt(RMS Power X impedance of the speaker)

So... sqrt(1000 X 1 ohm) = 31.6V

I set my gain to 31.6V so it should have gave the sub exactly 1000W RMS right? If I remember correctly the sub was in perfect working condition when I first installed it but as I started listening to different music I noticed this sound so I don't know if I messed up the sub or if I got jipped.

Please let me know your thoughts on this. Thanks

Vids:

http://www.youtube.com/watch?v=wjNe0J5NBs4

http://www.youtube.com/watch?v=B8jWSvGYmFo

Click to read more...

 

[grimreper912003 5,000+ posts]

Its hard to tell exactly what it is. try pushing on the cone. If it sounds weird report back.

 

[ZIG~ZAG 10+ year member]

Bad ground,, blown voice coils, ground wire may not be large enough, check the speaker wire. it could be anything!

 

[aarunt1 10+ year member]

The cone feels fine when I push it down. No weird sounds everything seems smooth. The suspension is still very stiff.

However, I originally had the sub wired in parallel to achieve a 1 ohm load. Since my amp puts out 600W RMS @ 4 ohms I thought I would give that a shot and wire the sub in series for a 4 ohm load. I hooked everything up and went to test it but....nothing happened. My amp was on and it was playing the tone but no response from the sub so I'm like WTF. I doubled checked my connections and they're good. I then hooked up my old SI Mag D2 the same exact way and it works! I then hooked up the sub backed into parallel for 1 ohm and test it....and it works again! So now I am super confused. So I decide to bust out the multimeter and check the terminals. The first terminal seems okay, fluctuates from 3.0-3.1, kinda weird but at least it was pretty stable. Checked the second terminal....no response. WTF so one of the voice coils is blown???

DVCs always confused me because it looks like a single coil I never understood how there are dual voice coils. Is it one around another or one on top of the other or wat because I can see the voice coil through the magnets and it looks fine. If a voice coil was blown wouldn't I have trouble pushing the cone down and would see it all messed up inside? I also thought a blown coil would give crazy fluctuations when checking for its resistance but I simply don't get anything. Could one of the tinsel leads possibly be broken and the sound I'm hearing is tinsel lead slap???

I'm really confused. Comments?

 

[pr-festiva 10+ year member]

you got an open coil time for a recone or a new sub

 

[grimreper912003 5,000+ posts]

The cone feels fine when I push it down. No weird sounds everything seems smooth. The suspension is still very stiff.
However, I originally had the sub wired in parallel to achieve a 1 ohm load. Since my amp puts out 600W RMS @ 4 ohms I thought I would give that a shot and wire the sub in series for a 4 ohm load. I hooked everything up and went to test it but....nothing happened. My amp was on and it was playing the tone but no response from the sub so I'm like WTF. I doubled checked my connections and they're good. I then hooked up my old SI Mag D2 the same exact way and it works! I then hooked up the sub backed into parallel for 1 ohm and test it....and it works again! So now I am super confused. So I decide to bust out the multimeter and check the terminals. The first terminal seems okay, fluctuates from 3.0-3.1, kinda weird but at least it was pretty stable. Checked the second terminal....no response. WTF so one of the voice coils is blown???

DVCs always confused me because it looks like a single coil I never understood how there are dual voice coils. Is it one around another or one on top of the other or wat because I can see the voice coil through the magnets and it looks fine. If a voice coil was blown wouldn't I have trouble pushing the cone down and would see it all messed up inside? I also thought a blown coil would give crazy fluctuations when checking for its resistance but I simply don't get anything. Could one of the tinsel leads possibly be broken and the sound I'm hearing is tinsel lead slap???

I'm really confused. Comments?

DVC are wrapped on top of one another I believe. A blown coil can be a short, break or melting of the coil. You could push it just fine. In some cases the coil unwinds and it would make it hard. It could be a tinsel but I doubt it.

 

[SPLaudio 5,000+ posts]

blown coil or bad tinsel lead....

 

[aarunt1 10+ year member]

Thanks for the replies. I guess that's the case. I probably should have just have run it at 600W RMS @ 4 ohms to begin with. **** BP1200.1 has messed up too many subs lol. I don't plan to recone it. Do you guys think anyone would buy it blown? If not I'll just take it apart and check out what happened to the coil.

 

[tylork92 10+ year member]

throw a DMM on it and check the coils.

 

[aarunt1 10+ year member]

I did in a previous post. One doesn't give a reading. The other seems fine though.