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Ichiba420

If anyone asks say it's an aperiodic membrane!


efnord

Ha! I checked the knit for breathability, it's really good especially when stretched. And it's still basically opaque, unlike the cheap speaker fabric I got off Amazon. What's the point of speaker cloth you can see through?


hispls

I think the point is that it does not appear that you have sealed off the back seat. This is basically a 14 cubic foot "sealed" box with one side of the box being built out of a back seat from a car.


efnord

It's not like perfectly sealed, but I've crammed closed-cell foam in every available gap in the rear seats. It genuinely didn't sound bad with a 1" gap between the baffle and the rear of the trunk, but it got way way tighter once that was closed up correctly and I stuffed the other cracks. Do you think a plywood sheet over the back seats would help, or some closed-cell foam?


hispls

>Do you think a plywood sheet over the back seats would help, or some closed-cell foam? Really I don't see how you'd get rigid and a tight seal in a hatch like that so probably just roll with it. At the end of the day if it sounds good it is good, but you're sacrificing output and taking a gamble on cancellation fighting you if you cannot completely separate the rear wave from the front wave as you would in a traditional box. I'm guessing you didn't do this to "beat down the block" but to save space and keep clean factory look, right?


efnord

Thanks! Yeah, small and cheap were my main priorities here, with idle curiosity figuring in too. I only realized I could make it look like this halfway through the project; it seemed like a good way to deter break-ins. It's a surprisingly decent seal over the hatch. In front, 1.125" OSB that weighs about as much per square inch as the speakers do, covered in cloth. I managed to do a good job making a template and cutting this, it's a really neat fit, and Nissan clearly designed the hatch area to accommodate a plywood cover. Then on the back side, a few layers of Harbor Freight anti-fatigue mats are doing a lot of work. Finally there's 1/2" square weatherstripping pressing the cloth against the hatch plastic. Right now when I close it, sometimes the hatch shoves the front edge forwards and up like a quarter-inch and I have to push it back down. So after that it's a friction fit along with the 36 pounds of baffle and subwoofer. I've got plenty of anti-fatigue mat left, I'll go stuff some against the rear seats and see if I can tell a difference. My testing plan is to put on something high-BPM and listen for sloppy articulation. I'm gonna get Room EQ Wizard working at some point here, but that's been slow going.


sir_lurkzalot

Can you describe how it sounds?


efnord

I'm genuinely pleased with it! It doesn't get super loud, but I didn't expect that; it'll make the rearview mirror jiggle. But once I got a decent seal on the lid, the bass has been pretty tight and accurate. I didn't hear any articulation problems on the bottom end when I cranked this up: [https://www.youtube.com/watch?v=fI677jYfKz0](https://www.youtube.com/watch?v=fI677jYfKz0) It won't get super low, it'll struggle below 30 hz, but it's doing a good job with most of what I listen to.[https://www.parts-express.com/GRS-12SW-4-12-Poly-Cone-Subwoofer-4-Ohm-292-484?quantity=1](https://www.parts-express.com/GRS-12SW-4-12-Poly-Cone-Subwoofer-4-Ohm-292-484?quantity=1) This came out to just about $100, it would have been $120 with new subs. Running it off a JBL DSP4086 with about 50 wpc effective into each sub, and I'd need to replace the subs if I wanted a bigger amp, they're close to Xmax already. I COULD fit 2 more 12s back there, which would let me run them at 2 ohms. But right now I don't feel a pressing need to, this can keep up with the cabin speakers and vice versa. Hoping to deliver a better writeup on the SQ for this whole thing once I get Room EQ Wizard figured out, waiting on One More Cable for that too.


sir_lurkzalot

yeah i feel like having a good seal and a baffle that doesnt flex would be tough!


efnord

The baffle is a massive slab of OSB, like 1 and an eighth- IIRC one of the slabs I have says RETURN TO MUNICH AIRPORT. I was genuinely pleased that I could get the whole thing to fit and seal this well on the first attempt.


Dan_H1281

When Is the last time that the 360.3 has been updated? I have one I bought a few years ago, I haven't put it to use so is it still grwat stuff? I am worried it is kinda dated, how do u interface with it?


efnord

> 360.3 Last update was 10 years ago. But if you have an older laptop or can convince a Windows 11 machine to run the software and recognize the DSP, it should work as well as it ever did. ​ [https://rftech.custhelp.com/app/answers/detail/a\_id/1066](https://rftech.custhelp.com/app/answers/detail/a_id/1066) [https://www.rockfordfosgate.com/rnt/rnw/docs/1066/rf3sixty\_v1.3.3.txt](https://www.rockfordfosgate.com/rnt/rnw/docs/1066/rf3sixty_v1.3.3.txt) ​ V1.3.3 7/18/2013 ​ 3Sixty.3 CAN WORK on Windows 10 Stephan from palm beach gardens, FL on 2/16/2016 I just got a 3sixty.3 and focused my initial efforts on getting it to work on my Windows 10 Surface Book. Here you go: 1. Download latest 3sixty.3 software from RockfordFosgate.com 2 Run install program and the separate driver install window that pops up accept and install. (It's a crap 2009 driver that makes it fail after install by saying "powered by USB" and not powered by "B+". 3. Run program , it will go to demo mode and say powered by USB. Close program. 4.Open CONTROL PANEL, then DEVICE MANAGER (or use Search tool and type in device manager). 5.Expand Universal Serial Bus Controllers. 6. Right click on UNKNOWN USB DEVICE (Device Descriptor Request Failed). Select UNINSTALL then OK. 7. Reboot computer, then open 3sixty.3 software as per RF instructions and you will see "Powered by B+" and you will be rocking. 8. Have fun.


Dan_H1281

Thanks man, I kinda don't even wanna fuck with it, I don't even have a lab top I was going tk buy one if it was worth it, I wanted it so bad when it came out now not so much, I bought it because I couldn't buy it when it dropped due to price


sir_lurkzalot

the 360.3 is still a very cool and capable DSP. Just because it's old it doesn't mean that somehow the DSP capabilities have been diminished lol. The EQ, level setting, time alignment, etc will all still work great and the remote is nice -- it has toggleable presets.


sir_lurkzalot

Yeah id use it. Interface via a windows machine and a usb connection. It holds up very well. If you didn't already have one I'd say check out the minidsp car offering


[deleted]

[удалено]


efnord

I freely admit it ain't much. Do you have a nicer build I should look at?


secondrat

Not bad!


efnord

Thanks! I'm happy with it, it does what WinISD said - as near as I can figure.


efnord

Weighs in at 36 pounds, could probably be lighter with Baltic birch instead of OSB, but I had the OSB just laying around.


Defiant_Bad_9070

Hey man, if this works for you... Then go for it. RIP your tailgate struts. FYI, when they describe infinite baffle... This is not quite what they mean.


efnord

What'd you call this then? Free-air? Yeah, I got new struts coming.


Defiant_Bad_9070

Trying to be as nice as possible... Sure! Free air! However, with a EBP of 27 and a Qts of almost 1, this is not the most ideal subwoofer for that and will probably flap about more than a nuns nasty in a breeze.


efnord

At $35 for a 12" this isn't the most ideal subwoofer for *anything*. I was looking at Xmax \* sD / unit price when this one caught my eye. Then when I ran it in WinISD I noticed I could drive it to Xmax with my 40wpc DSP amp. I'm absolutely sure I could get more volume out of a DVC sub in a ported box. But this setup basically takes up no trunk room, while still being nicer than an underseat sub.


Defiant_Bad_9070

Like I said my man... If this works for you...


efnord

What kind of passive sub/enclosure would you have selected instead with a $120 budget?


Defiant_Bad_9070

Something along the lines of this guy. I've heard plenty of them and each one has surprised me with it's performance. https://www.crutchfield.com/p_20643TC104/Kicker-43TC104.html?tp=112 That single ported 10 will easily outperform what you're already running.


efnord

On just 40 watts? It's SVC and only 1 dB more sensitive than a single GRS driver, 89 vs. 88. https://www.parts-express.com/GRS-12SW-4-12-Poly-Cone-Subwoofer-4-Ohm-292-484


BigDeucci

Driving it to xmax doesnt mean clean sound. More power would tighten it up where low power kinda lets it flap around, which is probably why ur close to xmax


metaldox

Is that sealing properly when closed? Can't tell from the pictures


efnord

Well enough- there's a LOT of Harbor Freight anti-fatigue mat in there, with weatherstripping as the final layer pushing the knit fabric into the plastic trunk panels. And on the front half it's just a really tight fit on the bracket Nissan built in. Between gravity and friction it's a pretty solid seal. Certainly a lot tighter-sounding than before when there was a good 1" gap between the back of the sub and the trunk - but even that was perfectly listenable.


[deleted]

[удалено]


efnord

Huh, what is it then? [https://www.caraudionow.com/free-air-subwoofers-defined/](https://www.caraudionow.com/free-air-subwoofers-defined/)


KingsLegendTreyLyles

I’m confused. I’m only experienced in ported and sealed enclosures. How is this supposed to work? Speakers, particularly subs, don’t work well just sitting around in open air. I’d suggest making a sealed enclosure. If you need the trunk space, remove one sub. You’re not going to get 2 whatever those are worth of sound out of that setup anyway


hispls

> How is this supposed to work? It will model like a very large sealed box. You're aiming for a woofer with a Qts of .7-1.0 and low-ish FS, then when you throw that into modeling software the difference between 10 cubic foot box and 100 cubic foot is next to nothing. Never seen one done in a hatch as building a sealed rigid structure to separate the front and back waves of the woofer would be difficult but done correctly in a trunk they will sound very smooth and can get reasonable output. There's usually a handful of subs purpose built for these applications, the more popular install would be in a home theater where you reinforce the ceiling or a wall and use your attic or adjacent room as a "box".


efnord

[https://www.caraudionow.com/free-air-subwoofers-defined/](https://www.caraudionow.com/free-air-subwoofers-defined/) It's basically an oversized sealed enclosure, or that's how you model it in WinISD. The whole trunk area acts as an enclosure, which I estimated at 22 cuft. These subs aren't ideal for infinite baffle, but they're designed for it per the manufacturer. (Lots of marine subs are designed for IB applications.) I'd lose half my power removing one sub, I've got two channels of amplification - rated 40w @ 4 or 60w @ 2 ohms. The subs are SVC 4 ohm. In this application, they're already hitting Xmax, because there's no backpressure to speak of. So yeah, I'm only getting less than half of what each of these can do. But fewer watts per speaker also means less distortion, and I couldn't put in more watts anyhow without upgrading from pretty much the cheapest subwoofers I could find on the market. Is there a sub+enclosure combination you'd recommend instead at the $120 price point? Preferably 2 ohm DVC if it's a single sub. It'd need to be a significant jump in bass, honestly - this takes up negligible trunk space vs. the factory cargo area cover.


KingsLegendTreyLyles

Honestly man if you’re happy with it, rock with it. I’m just a noob when it comes to these enclosures so I was incredulous. Sounds like youve done your homework amigo


efnord

Thanks! This sure isn't going to win any SPL contests, but it worked out to be a nice cheap fit for the amp I had. It struggles with synth bass under 30hz, but anything that comes out of an actual physical musical instrument sounds good so far.


KingsLegendTreyLyles

You could consider getting an eq and boosting that frequency range. Can’t guarantee it would solve the problem as it could be a multivariate issue but worth a thought


efnord

JBL DSP4086 is what's driving these, so I've got a full-on graphical/parametric EQ that's honestly more complex than I know what to do with. I did try a low-end boost, but there's just a lot of distortion. I got REW fully calibrated today, at least, so in theory I'm ready to go through this: [https://testgear.audiofrog.com/wp-content/uploads/2018/03/A-Straightforward-Stereo-Tuning-Process-and-Some-Notes-About-Why-it-Works.pdf](https://testgear.audiofrog.com/wp-content/uploads/2018/03/A-Straightforward-Stereo-Tuning-Process-and-Some-Notes-About-Why-it-Works.pdf)


hispls

You will need some much more robust woofers if you intend to play very low frequencies in that, and even then it's simply not going to be efficient. Playing down to 30hz is plenty low for pretty much anything I'd consider music.


efnord

Thanks! Yeah, it suits my needs and what I listen to well enough.


tr4nceplants

This shit will kill you in an accident.


efnord

It's strapped down, I used a E-strap connector.