Hey guys. Now before anyone posts a reply in response to the title without reading the thread, I KNOW this is an el cheapo brand, but it was all given to me in exchange for some mechanic work so for basically free I'm not going to argue and just do with what I have (For now).

I was given two 12" hifonics subs model hfi12d4, a 2x 12" box and a capacitor. I am keeping one the subs for myself, going to flip the other sub and the box and contemplating on whether or not to use the cap.

I am going to put the sub into a single 12" box and toss it in the spare tire compartment. It si going to be driven by an oldschool alpine amp which pushes 180 watts RMS in 4ohm mode. IIRC that should be 240 watts RMS in 2 ohm mode (Which this sub is capable of when both voice coils are wired in parallel). I am not sure if this amp is 2ohm stable but I guess we will find out .

My question is what should I expect out of this sub? I know for $40 a pop it won't be kicker quality, but I was hoping for something decent. I'm not looking for crazy earth shattering bass just want something that hit some clean lows in the 20 or 30hz range and put a little bump in my trunk.

Right now I have a CDT 6.5 component set in my sails and 4x6 infinity kappas in the dash driven by a kenwood amp and a pioneer head unit. The sound output and quality is phenominal, but the low end bass just isn't there.

 

Want to sure I'm reading this right.

You have an amp that is able to go down to 4 ohms.

and you have a dual coil sub that is 2 or 8 ohms right?

What can you expect if you you wire in that sub at 2 ohms to your 4 ohm stable amp? A fried amp.

That amp/sub combo is not going to work. You will either need to run both subs with the coils ran in series 8 ohm each, and then run the speakers in parallel (4 ohm).

Or get an amp that is able to be run at 2 ohms.

 

This is the amp I will be using (In fact you're one of the ones that commented in the thread)

https://www.thirdgen.org/forums/car-...heard-amp.html

All the speakers in the car are driven by a separate 4 channel Kenwood amp. The Alpine amp is going to be driving the sub ONLY.

What would happen if I connected only one of the 4ohm voice coils?

I am not sure if this amp is 2ohm stable. I can't find any documentation on it due to It's age.

 

decades ago,hifonics was one of the best car speaker and amp manufacters there was;i have 30x30 hifonics amp from 1979 still rocking in my car-made in usa and sounds great-never mind it is from the tail end of the disco era I'd try that old alpine amp at 2 ohms and see if amp heats up or distorts-if it does,try it at 8 ohms and see if the sound is satisfactory.

 

I guess I should clarify. It will be 2 ohms stable in stereo mode, but not bridged. I wouldn't even bother running it off of just the left or right channel. There just wouldn't be enough power to make it worth your while. Plus that would sound odd I'm pretty sure too.

I wouldn't run it off of one coil either, not sure if that would damage the sub over time or not, but it wouldn't sound good.

Running the sub at 8 ohms, you're amp will be putting out about half what it could be doing.

You either need to: Use both subs, buy a single coil 4 ohm sub, or buy a mono 2 ohm stable (bridged) amp and use it with that 1 sub.

 

cdoyle has covered it all, but I just wanted to throw in my .02...sell the cap.