Strange issue - intermittent loss of low bass <30HZ 2 Fi SSD 12

[vypr 0]

Hi,

I have a strange issue that seems to be getting worse. Ill start from when I think it happened. My friend and I built a 4CF box for 2 FI SSD tuned to 30HZ. When we put the box in my cobalt I noticed that the wire terminals were upside down. I didnt care at the time I was just wanted it done for the time being. This was back in 2010. A few weeks later I decided to have my other buddy help me remove the box and put it in the right way.and reposition the subwoofers so that the labels looked the right way. When I was reorienting the subs I unhooked one completly to show my buddy,turns out when I hooked it up I wired the coils out of phase. I didnt know until I was on my way home when I turned it up and I smelled coil burning. So i took the sub out and rewired it correctly. Seems now I have no low bass, but sometimes I do, Like that sub has one shorted coil or something. The suspension is tighter on the sub that I had the coils wired out of phase. the coils are wired in series on both then parallel to the amp for a 2 ohm load. The loudest frequency used to be 25HZ now its closer to 33HZ big difference too. also bass is weaker. So I am thinking that one coil on that sub is intermittently shorting out. it makes sense because of less force on the speaker that the suspension would be stiffer. there is no rubbing or anything. I was thinking of reconing that one subwoofer. but wouldent I have to do both? since one will need to be broken in?. My setup is a avh-p4200DVD DC power SP250 alt, xs powerd3100 battery, t20001bd@ 2ohm. All RF 1/0 wiring RF RCA. 2 12 FI SSD with BP power. t600-4 all RF components. I would like someones thoughts on my issue. Its drivin me nuts. I was so fruestrated I almost went and bought new subs lol.

Thanks

[shizzzon 461]

i'd say unhook one sub altogether and troubleshoot them separately.

[vypr 0]

Hi shizzzon,

Thanks for your reply. I have the subs in a common chamber. That would still work right? or would the unhooked sub color the sound too much?

[shizzzon 461]

just dont go slammin on bass on 1 sub. Twice the volume, lot less power needed to move

[vypr 0]

okay, I will try that when I get home from work this evening and post what happened. I hope its not the sub. but it probally is. nothing else it really could be.

[shizzzon 461]

if each sub plays fine separately then there is a wiring issue

[vypr 0]

^{Yea, I will also check the solder joints on the terminals in the box from the subwoofers. i will check the DC resistance should be like around 3.7 ohm or so for dual 2 ohm wired in series?}

[vypr 0]

Sorry about the font being messed up

[jesseadkins187 5]

broken lead.. on one coil.... get a ohm reading off each coil and see what they read then hook up one coil individually and play it on low volume.. see if it cuts in and out..

[vypr 0]

Hi Jessieadkins.

Thanks for your reply. I have the coils in series, I would really lose volume if the sub was totally cutting out. not sure though never just played one. the ohms are identical on the subs like 3.6 to 3.7 ohms on each. Its making me nuts. Thats wht I thought maybe one coil is shorted out on the series wiring it would be just like a single 2 ohm sub.

[vypr 0]

My theory was when one of the coils heated up it shorted out causing my loss of low bass because of the less force with the sub only using one coil vs 2

Edited May 2, 2012 by vypr

[SubSam 21]

Check for any damage to the enclosure, ie loose baffles or air gaps. About a decade ago I bought a prefab ported box that had weak screws holding the rear panel on. Depending what direction I turned my car the box would bend and throw off the tuning bigtime (last prefab I ever will buy or sell). Only thing I can think of if its not a wiring issue.

[///M5 2,833]

I'd still bet there is a wiring concern. Re-attach everything. Surprising how little details can act very strange when it comes to electronics.

[vypr 0]

Bad solder joint on one of the speaker terminals on the box. I built a new box and ran wires straight out. works great. Thanks for all your help!!

[ShawnFleming 50]

Just saw this, as I was reading down the post I was racking my brain on what the problem could be with the sub, and I couldnt think of anything that would cause that(on the sub side). Glad you got it figured out.