king nothing

Sounds like a good plan. Except the infinitys lol

Daimyo68

Ok, yet another (age old) question that can hopefully be answered here pertaining to the woofer/s and box. I'm going to build my own enclosure for the woofer/s, sealed box (again going for tight/solid sound, and I get to take some pride in what I built).

The PPI 900.5 amp, the sub channel will put out the following:
RMS Power @ 4 ohms - 270 watts x 1 channels
RMS Power @ 2 ohms - 440 watts x 1 channels

With this information, I could go a couple ways (I think):

Single 10" DVC woofer, 2ohms, not exceeding the 440w RMS
or
Dual 8" DVC woofers, 2ohms/200'ish watts each (not exceeding the 440w), wired in parallel? (Image Below)

Or I could find 2, 10" and wire them in parallel. (if the wallet doesn't start screaming).

Rec's, arguments?

Wyo11Scab

iTrader: (1)

I like doing it this way

"Or I could find 2, 10" and wire them in parallel"

king nothing

Yep. What he said. Whatever you do don't run any of that shallow mount crap. Use a real sub

Robert8252

Two single 4ohm vc speakers will work as well as two dual 2ohm speakers to get a 2 ohm load. And short and sweet don't worry about power matching exactly. That amp is max pushing out 450 watts at 4 ohms. if you have two subs rated for 200 each they will be fine as long as you set the gain properly.

And everyone does what they want but I have ran the Hertz Energy, Hi Energy, and Mille series of speakers and they are the cream of the crop. Infinity lack a lot of detail in the mids IMO and the tweeters are VERY harsh. I ran two set of the Kappas in my front doors of my last car and was so happy when I got rid of them. Also sound deadening in the doors matters as well. It doesn't matter if you have a $20 speaker or a $800 speaker, the $20 could blow the $800 speaker away if the install isn't good. If using stock location I would do a layer of sound deadener inside the door as well as the entire panel the speaker mounts to. I prefer Second Skin Damplifier but there are plenty of options to choose from.

KILOFINAL

Yeah, I'm running Hertz speakers in my truck and love them. The audio shop also made sure the doors were reinforced with additional matting to reduce resonance/vibration.

Daimyo68

I had time to go out to the truck and make some measurements for the sub box, and after doing that and building a box in SketchUp.

I'll DIY my sub box.

I'm currently looking at RF P3SD2-10 subs or the 8" version (shallow mount, but this means I don't have to make any additional parts for a regular depth sub). They are 300w RMS each. This would mean going with a dual amp setup though (which isn't that big a deal), as the originally planned PPI 900.5 will not supply enough RMS power for them.

Question I have now is with the 10" sub installed, I will have from 7/8" to 1.25" of clearance between the magnet and the inside top of the enclosure (roughly 1" at center). Is this enough room, or will it be an issue?

Sorry that I'm all over the place with the sub setup/design, just being too **** I guess.

Robert8252

There is no need for a lot of space behind the magnet. And the subs will still work fine with that amp. Generally making the box a little bit bigger will make up for the lack of power in this situation.

P.S. - If you want to learn more Google "Impedance Rise" It doesn't matter what you do you're never going to get all of the power out of an amp in normal use. Rockford makes an amp to help with this as well as JL audio that deliver "constant power"

P.S.S. - Also, just because a speaker is rated to handle 300 watts doesn't mean it needs that. When you turn the volume down it doesn't keep getting "300 watts". There is no audible difference to the ear in your situation as well. Having 600 watts instead of 440 would barely be a single decibel louder which isn't noticeable to the ear. You would have to double the power to almost 900 to notice a big difference and that would only be 2-3 decibels.

Daimyo68

This is nice to know. Being this is the case, I can still go with the single amp.

Daimyo68

Here's the box designed and finalized, I think. Obviously the same rough shape as other builds/designs. The box will be completely under the seat (not protruding beyond the edge of the seat), with 1-3/4" clearance between the floor and the downward facing subs.

I researched for countless evenings on the subject of proper design, used many calculators and several sheets of paper, as well as many SketchUp renderings.

The completed box has 2 sealed chambers, a shared center wall, with the final volume of each chamber being .49821 with the subs installed (.55920cf without the sub installed).

I just want to confirm my cf calculations:

The RF P3SD2-10 subs call for .50cf in a sealed chamber.
Each chamber is .5592cf
Subtract the speaker .cf of .601 (installed) and my final chamber volume is .49821cf

Is this correct or does the cf of the sub itself not get subtracted from the chamber cf? (as in, do not calculate for the subs offset to the final chamber cf).

If the chamber cf is the only thing I need to be worried about (leaving the sub's offset out of the math), then it's as simple as changing the length of each chamber.

(I just used a generic speaker for measurement purposes).