New to forum, just got first sub and amp installed: question about bottoming out

Just throwing it out there because it hasn't come up yet: another option is to add another woofer to the box you have. Cutting the box volume in half only loses about 3 dB at 25 Hz, and less as frequency rises (about 1 dB at 50 Hz). Doubling the drivers should give you 6 dB more output capability vs a single, so you should still come out net positive for the transaction across the entire range, and up about 5 dB at 50 Hz.

Qtc would only be 0.82 ish, so not a crazy number.

It would keep excursion under control more effectively also. But I don't know how much more output you really want, and I didn't check into your amp/impedance situation.
 
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Not to be negative
But been slapping subs since the 90's

the sensitivity of 10 inch subs and usual Fs you get
is a waste of time.

I dont need contest winning bass
But I like my rear view mirror to blur, lol
with least power as possible.

Use 12" with high sensitivity
2 of them
No ports needed, they unload.

2x12 sealed and your done.

I had one 12" down in my latest setup
and a single 12" wouldnt make me happy
and a 10" wouldn't even do that.

You dont need mind blowing Xmax drivers
You just run 2x drivers with higher sensitivity.
And 2 speaker reach SPL easier and you get xmax simply using 2 drivers as well.
 
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You can mount them in cone to cone isobaric or both inverted.

Edit:
You'd mount them inverted. Mounting them cone to cone wouldn't solve the problem.

If the voice coil is actually bottoming out, the woofer may be a factory defect. Go to the shop where you bought it and see if you can make the coil bottom out by pushing on the cone as you can when you push on yours. I'm assuming that the cone bottoms out sharply and not gradually. Which is true?
 
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how would a two sided sub box work
Mounting on opposite sides as in the image below cancels some box vibrations, so it's often used because of that.

https://www.diyaudio.com/community/threads/definition-of-push-push.365561/
1712890686734.png


But you can put them on adjacent sides, one facing in and one facing out, or however makes sense for how you want to use them. You obviously need to wire them so they're both pushing out at the same time, so that can require different wiring polarity if you flip one inside out.

My quick run at the numbers didn't imply that you were near trouble from a box volume standpoint even with two of the Vega 10's in your single box, so I wouldn't be too concerned about maximizing the internal volume. Sealed enclosures tend to be pretty forgiving of reasonable cabinet volume changes, and your particular woofer looks very forgiving in this regard.

Your original Qtc with one woofer in that box looks like about 0.65. A Qtc that low helps with very low end extension, but also lets the woofer move more at low frequencies, so it can be easier to use up all of the excursion. Maximum power handling for a woofer/sealed box is up at Qtc 1.1, and even with half your current cabinet volume (as would happen with two of your woofers in one box) you get less than halfway to 1.1 from where you started.

The trade-off for raising the Qtc is sacrificing some low end extension and transient ability, but again, in your case that looks pretty minor and cabin gain typically helps you out as frequency decreases anyway.

As I suggested earlier, I'm not saying this approach will necessarily get you where you want to go, but it's an option that looks reasonable if your amp can deliver enough power to both woofers.
 
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Mounting a second, identical woofer as mattstat pictured in post #51 is your only option. You will get +3dB from the extra cone area and another +3dB from the double power the amp can deliver at 2 Ohm. You now have 4 Ohm, with the second woofer in parallel you get 2 Ohm.
This +6dB should give you quite some extra headroom. As mentioned, you will loose some deep bass, but this is not relevant for you anyway.
What you have to do is to make clever use of the low cut. Set it to 40Hz. You will not loose any audible bass, but save amp power that is wasted otherwise and can be better used for the audible part of the low spectrum.

Not using the low cut will overload amp AND woofer. I hope you understand?
 
PS
if you do not do things your self, as many in this forum do, anything audio quickly get's expensive. Buying first and asking later takes away the option to discuss the best solution with independent experts, as the budget is spent.
In your case, for your demand, a vented enclosure, tailored to your trunk, with 2x 12" would have delivered what you expected. Done right it doesn't take away much more useable space than your cube. Anyway, such a perfect solution is a little more expensive than just throwing a China made box in the trunk...
 
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If you don't care for the look of it, best would be on opposing sides, of course. Second, have both magnets on the outside. You win a fair amount of valueable volume and have the cooling at optimum. Fix the cabinet in the middle of the trunk.
While vented cabinets are very critical to volume and the port dimensions, the closed ones are not and have quite some tollerance field. So don't listen to the stuffed shirts that complicate anything to sell you stuff.