Which amp to use

[Cwrig]

Okay, so it's been at least 10 years since I've done an install, and I've only ever installed SVC subs. I'm not looking for earth shattering bass, just a well rounded sound in this truck I just bought, so with limited space, I bought an 8" DVC 4 Ohm shallow mount RF woofer with a 150W RMS (300W max). I have two old amps, and I'm not sure which will be the best option, since I can't deliver a 4 Ohm load to the amp.

One amp is an ancient RF Punch 2 channel 50W x2 RMS at 2 Ohm. I had this one hooked up to the new sub, wired parallel to deliver 2 Ohms, and it sounded great, but it ran incredibly hot within just a few minutes. I believe this is because I had it bridged. The second amp is an old Alpine mono 200W RMS at 4 Ohm/350W at 2 Ohm.

So basically my question is this: would I be better off A) sticking with the parallel wiring on the RF amp, letting it run hot, B) not bridging the RF amp, or C) switching my wiring to series and using the Alpine amp at 8 Ohms? I'm worried that the RF would underpower the sub, but I'm also concerned that using the Alpine at 2 Ohms will overpower and blow the sub (it blew an old MB Quart sub I had with that setup yesterday, hence the new RF sub). Or if anyone has any other suggestions, I'm open. Any insight is appreciated.

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[garychoffmann 10+ year member]

Wire to 2 ohms on the alpine and set it to deliver a clean 150-200 watts. Multiple ways to do this but youtube setting gains with a dmm

 

[BOOMINGRANDPA 5,000+ posts]

whats up nc guy.. yeah u can try the alpine see how it sounds.. am I confused u said sub is d4 so wire to 2 ohm and hook the alpine to it for 350rms and set gain low (my sub rated at 600 I'm running 938 others here run 1500rms to 500rms subs, set gain low no need for bass boost).. anything less that that ain't worth the trouble anyway.. and if that's not enough power for u I have a autotek 1600 (500rms @2ohms) 4 months old (just got bigger amp 3 days ago) i'll sell u that for $50 if u ever drive close to Sanford, if u want to run 2 subs or get rid of that and get a 12..

 

[Cwrig]

Thank you both for your suggestions. I'll leave the sub wired at 2 Ohms and set the gain to provide 150W until it's broken in.

whats up nc guy.. yeah u can try the alpine see how it sounds.. am I confused u said sub is d4 so wire to 2 ohm and hook the alpine to it for 350rms and set gain low (my sub rated at 600 I'm running 938 others here run 1500rms to 500rms subs, set gain low no need for bass boost).. anything less that that ain't worth the trouble anyway.. and if that's not enough power for u I have a autotek 1600 (500rms @2ohms) 4 months old (just got bigger amp 3 days ago) i'll sell u that for $50 if u ever drive close to Sanford, if u want to run 2 subs or get rid of that and get a 12..

I appreciate the offer. I actually have 2 Kenwood 12"s laying around from a previous install, and a 1000W 1 Ohm stable JL amp. I just don't need that much boom or want to occupy that much space under the back seats. Although, now that I've been working on this, my wife has decided she "needs" the 2 12"s in her car.... //content.invisioncic.com/y282845/emoticons/rotflol.gif.b453361716769b8110ddefc85ff03cd2.gif

 

[Stellar1024]

Keep in mind, if an amp is 2 ohm stable minimum... when you bridge it, it will be 4 ohm stable minimum. That likely explains why the fosgate over heated. Also, those old amps are underrated so the fosgate is probably more powerful than it states... I'd first try running the Fosgate not bridged.. if it doesn't sound good, try the Alpine. If it still gets hot, try wiring series.. basically trial and error..

 

[BOOMINGRANDPA 5,000+ posts]

Thank you both for your suggestions. I'll leave the sub wired at 2 Ohms and set the gain to provide 150W until it's broken in.


I appreciate the offer. I actually have 2 Kenwood 12"s laying around from a previous install, and a 1000W 1 Ohm stable JL amp. I just don't need that much boom or want to occupy that much space under the back seats. Although, now that I've been working on this, my wife has decided she "needs" the 2 12"s in her car.... //content.invisioncic.com/y282845/emoticons/rotflol.gif.b453361716769b8110ddefc85ff03cd2.gif

u and i have very different wives., mine told me this morning if i put my sub and old amp in her car she'd kill me., i was looking for excuse to get new sub lol..