Where's the bass?

[Beau M 10+ year member]

Hello all

I've been into this car audio thing for 20 years, so I've seen a thing or two. I recently purchased a ranger extended cab pickup and put a modest system in it. For a sub I'm running a DD 512b in a pre-fab (I know, I know) box that is 1.7 cu ft and tuned to 33hz according to the manufacturer. The sub is brand new and only has bout an hour or play time on it. The sub amp is an Alpine MRV-M500, so around 500 RMS at 2 ohms.

My issue is there seems to be plenty of mid to upper bass, but not so much low end. The sub isn't flopping around and doesn't seem to be unloading. Putting the windows down seems to help a bit.

Is this a function of the extended cab, or should I be looking at my box, or are the DD512b's known to do this? I've played around with x-over points (Alpine does not have a subsonic) and EQ settings on HU. I am considering both sealing up the port and getting an epicenter, think that would help?

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[mylows10 5,000+ posts]

I doubt that box is 1.65 after displacement and port. Prolly tuned to high also

 

[Beau M 10+ year member]

Yeah, that's my fear. Not sure if it bothers me enough to build a new box though, might just seal this one up.

 

[hispls 5,000+ posts]

Have you tried firing the port into the corner? Experiment with rotating the box around and see how much difference that makes? Perhaps you just have unreasonable expectations out of small entry level sub in a small box?

 

[LosIsATool 5,000+ posts]

Have you tried moving the box around? Maybe flipping it?

 

[Beau M 10+ year member]

I want the box to stay where it is, works real well for packaging. Maybe your right, but I'm coming from a sedan with a Kicker L7 8" in a small sealed box (same amp) and remember it hitting the lows better.

Eh, I'm an old man now, I don't need crazy bass anyway, I can live with it. Probably just try sealing up the port and see how that goes, if no change then F it.

Thanks guys.

 

[LosIsATool 5,000+ posts]

Just flip it over. The port needs something to load off of. You are making my beloved DD look bad.

 

[Beau M 10+ year member]

There really isn't the room to do so, the side with the wiring is very close to the extended cab door panel. The whole box cant be scooted over either, the jack assembly is in the way. I don't want to fire it up as I will toss stuff on top every now and then, and don't want to fire it down as the 4-channel amp lives there. It would be easier to make a little wall for the port to load off.

This is my first DD sub, its not terrible. Got it for a good price. I just tossed in a bass track and it slams pretty good, but when listening to actual music its very peaky.

My last extended cab truck had a down firing Fosgate T1 15" run off the sub section of a Big Belle, it had no issues hitting the low lows. Bigger box, bigger woofer and more power, but sealed.

 

[C1500martin 10+ year member]

that box looks really small for 1.71 what are the measurements of it? by looking at it I'm guessing 18Wx14Hx16D? it looks like the boxes they sell here in downtown LA and they are tuned really high.

 

[Beau M 10+ year member]

I think you guys are right, box is too small. Shame on them for lying, shame on me for not knowing better. Here is the actual Amazon description from when I bought it:

I've only messed with ported a few times. What would happen if I increased the volume of this box while leaving the port length where it is?

 

[C1500martin 10+ year member]

well technically they didn't lie, they just used your ignorance (no offense) to sell a box. it is around 1.70^3 BUT thats gross volume. the actual volume the sub sees after all displacements is probably 1.38^3 or somewhere around there. it is tuned to 33 hz though if the slots measurements are 1.5x12x24.25?

 

[Beau M 10+ year member]

Seems my post didn't stick, but I went out with a tape and did some measuring. After subtracting wood and volume, you are correct it should be around 1.39cuft. I threw that and the port measurements in the calculator, and even if I'm a few inches off it checks out at 30-35hz.

Huh.

 

[Beau M 10+ year member]

Just read this on DD's website:

We recommend to allow at least several weeks of playing time to break in DD Woofers, full break in may take many months. DO NOT play subwoofers at max amplifier power in the first couple of days, give the suspensions a chance to loosen up. As the suspension breaks in, the subs will play lower and louder.

 

After you give the woofers a chance to break in (you'll know when this happens because the woofers will be playing lower and louder) you can start to look at port changes to alter the sound to your personal taste and your vehicles acoustic loading conditions.

Think this could be part of my issue? Does this apply to the lower lines like my 512b or is it just the monster subs?

I've heard people say sub break in is BS, and I used to believe it, but if the manufacturer is saying it...

The DD Box | DD Audio

Bottom of page.

 

[thatguy12 10+ year member]

That grill looks so close to the subwoofer. That would make me nervous. Small subs it's cool, but that looks risky. My two cents

 

[Based]

check your subsonic filter on your amp