Got a couple questions!

[davewms9605]

I have a couple questions. First off, What actually is impedence rise? And also, i know ive asked alot of questions on these forums but im trying to learn someting from you guys here!!! Ive looked at the Audioque site and was interested in the HDC3 12" subs. Im thinking of getting a pair instead of the walled 18's i was thinking about. I used the RE calculator and was wondering if this is correct for two HDC3 12's: Box dimensions...41"wX16"hX19"d, with 72.5" sq port area, 4.7 cf box volume and tuned at 35hz. is this correct for these? it will be installed in an 86 monte carlo ss.

[Marlo Stanfield]

I didn't run the numbers, but the box size seems about right for those woofers. A lil on the high side for port area though, depending on what kind of power you're running.

The DC resistance is the measurement of the coil at rest. When the cone starts moving, the magnetic field associated with the magnet and the moving coil increases the resistance of the voice coil. Usually the more resonant the enclosure, the higher the impedance rise. Most competitors try to factor rise into the equation so they can get the most power out of their amps. Impedance rise only happens at resonance,so at other frequencies the amp sees somethin closer to the DCR(ie music).

I'm terrible at explaining things online lol, so this was an explanation i found for ya on termpro.

[davewms9605]

I didn't run the numbers, but the box size seems about right for those woofers. A lil on the high side for port area though, depending on what kind of power you're running.

The DC resistance is the measurement of the coil at rest. When the cone starts moving, the magnetic field associated with the magnet and the moving coil increases the resistance of the voice coil. Usually the more resonant the enclosure, the higher the impedance rise. Most competitors try to factor rise into the equation so they can get the most power out of their amps. Impedance rise only happens at resonance,so at other frequencies the amp sees somethin closer to the DCR(ie music).

I'm terrible at explaining things online lol, so this was an explanation i found for ya on termpro.

I appreciate the quick response, and i was looking at the Audioque AQ2200D for power. If the port area is a lil high, what would you suggest? Something like round 60? but that would take it down to like 31 hz for tuning. Is that ok?

[Marlo Stanfield]

I appreciate the quick response, and i was looking at the Audioque AQ2200D for power. If the port area is a lil high, what would you suggest? Something like round 60? but that would take it down to like 31 hz for tuning. Is that ok?

Well u don't have to stick to that exact volume... Like 2.25 or 2.3ft3 per woofer would still work just fine, although idealy w/ only 1100w or so per sub you'd wanna go bigger to increase the efficiency. It would do better with that little power for those subs. 33-35hz would work well for those subs, but i know they suggest like 37-40hz for tuning in a daily box.

If u were really planning on running that amp(which is a great amp btw), then I'd run something more like a DC LVL4 or FI Q w/ that power.

[davewms9605]

Well u don't have to stick to that exact volume... Like 2.25 or 2.3ft3 per woofer would still work just fine, although idealy w/ only 1100w or so per sub you'd wanna go bigger to increase the efficiency. It would do better with that little power for those subs. 33-35hz would work well for those subs, but i know they suggest like 37-40hz for tuning in a daily box.

If u were really planning on running that amp(which is a great amp btw), then I'd run something more like a DC LVL4 or FI Q w/ that power.

Thanks again Marlo, but i was weighing cost and the HDC3 12's were in my price range, also, im not too familiar with these subs and when you said" that little power for those subs" kinda threw me back for a sec. Can these things take more power on a daily than the 1100 watts each i want to give them????

[davewms9605]

Bump

[Demo402]

Sounds Good Man GL with build