Upgrading to 15s, need recommendations

[brafferty]

i'd get the D1 so you can wire to 2 ohm for now and you can wire to 1 ohm if you ever plan on walling it later with two 18s. Read up on box rise, when you wire to 2 ohms, you'll actually be around 3-4 ohms after box rise. Dont ever think you are fully getting the rms stated out of any amp because it doesnt work that way, unless the amp is a constant power amp with regulated internal power supply.
Tune to 35hz-37hz for your genre though. You dont need to tune low with HDCs to hit the really low notes. Its not gonna sound shitty until you get above 40hz port tuning. I'm at 35hz right now and its still a bit geared for decaf and such, 37 would have sounded better on dubstep. These subs arent like other subs where you need to tune low to achieve any low notes. In fact, andrew mcollough, the owner of "the black nasty" (youtube it) did extensive testing and said 35 to 40hz tuning is best for these subs.

oK Soive decided, ill build the box first, tuned to 36 hz just to hit in between what you said, and then from there ill decide what ohms ill run it to, but ill stick with the single 18 for now, im sure this sub will blow me away, no one around my area differs away from kicker, alpine, or rockford,and idk about you guys but i really dont care for the p2 or p3s

 

[Jeffdachef 5,000+ posts]

just dont run Brazilians at half ohm and you'll be fine.

 

[Jakerrr 10+ year member]

oK Soive decided, ill build the box first, tuned to 36 hz just to hit in between what you said, and then from there ill decide what ohms ill run it to, but ill stick with the single 18 for now, im sure this sub will blow me away, no one around my area differs away from kicker, alpine, or rockford,and idk about you guys but i really dont care for the p2 or p3s

Idk if you've already made your decision or not, but I've been doing a bit of research myself for my next sub upgrade. I feel very confident in making this statement: If you're buying NEW, not used, the SQ hdc4 18" is currently the best value subwoofer for the $$$ you can get anywhere. It's a shame I won't be able to fit it in my trunk with it's volume requirements. I can just barely fit the 15 but it's only $10 less that the 18 and will likely yield significantly less output. I mean really, $10? Wtf... The 15 is very good to great value but the 18 is phenomenal performance/price. I'd go with Taramp's for power if you want a new amp as well, but you can find a Brazilian used. There's a PRV Audio in the classifieds here right now I don't think it sold yet. Also that 8k might still be f/s. Just get an amp that does 4k+ at target impedance and your sub will definitely see more than 2kw, which is the minimum it should run if you want to get the most out of it. You'll suffocate in bass

 

[Popwarhomie 5,000+ posts]

PM me if your looking to buy anything Taramps.

 

[brafferty]

Idk if you've already made your decision or not, but I've been doing a bit of research myself for my next sub upgrade. I feel very confident in making this statement: If you're buying NEW, not used, the SQ hdc4 18" is currently the best value subwoofer for the $$$ you can get anywhere. It's a shame I won't be able to fit it in my trunk with it's volume requirements. I can just barely fit the 15 but it's only $10 less that the 18 and will likely yield significantly less output. I mean really, $10? Wtf... The 15 is very good to great value but the 18 is phenomenal performance/price. I'd go with Taramp's for power if you want a new amp as well, but you can find a Brazilian used. There's a PRV Audio in the classifieds here right now I don't think it sold yet. Also that 8k might still be f/s. Just get an amp that does 4k+ at target impedance and your sub will definitely see more than 2kw, which is the minimum it should run if you want to get the most out of it. You'll suffocate in bass

ive decided to go with the 18", and having stang build me a box since certain things came up and i no longer have access to the tools needed, trying to decided what to tune it to, im thinking 36hz, but ill be running it off my JBL for about a month or 2 until i can upgrade, ill be ordering the box hopefully next week. im pretty stoked, im pretty sure everyone will agree even of my jbl this will be better than my alpines without consideration

 

[Jakerrr 10+ year member]

ive decided to go with the 18", and having stang build me a box since certain things came up and i no longer have access to the tools needed, trying to decided what to tune it to, im thinking 36hz, but ill be running it off my JBL for about a month or 2 until i can upgrade, ill be ordering the box hopefully next week. im pretty stoked, im pretty sure everyone will agree even of my jbl this will be better than my alpines without consideration

From what I've seen tossed around by people who've tested these extensively, for the new (not old) HDC4 18: 33-38hz. 5.5-6.5 ft^3. 5.5 for 4kw, 6.5 for 2kw.