lithium

Depends how you set the gain, what music you listen to, and at what volume level. Assuming you wired it up correctly and your car electrical can support the power.

The software looks a bit more thought out then my more expensive minidsp c 6x8

great build! Most ppl run LR xovers for whatever reason. No hard and fast rules in car audio.

I was looking at the replacement seat back part and noticed circles on the drawing. Turns out there are about 36 holes on the panel. I'm going to build a sealed enclosure for one of my subs and see how much bass pass through the rear seat as is.

That's fair. I'd rather cut the seat than the rear deck, but for now I'll probably try my 12" AA Arsenal sealed. Front stage is bit more important to me anyways. Planning to start with a simple two way with SSA components since I have a set just lying around. I'll probably get bored of that after a year or so and try some weird midbass stuff (underseat, kick panel, etc).

do you think stock opening in the rear deck would be too restrictive for 10s or 12s?

I don't want to cut the deck and do not have access to a welder. Still working out of my 1 bedroom apartment for now.

I think I could make 3x 10" work on the rear deck. Seems like the Daytons, modelled above, could get close to the same performance as the mach 5 mj18 I've run in my last vehicles. I need to see if 12s could fit. And if they do, would the stock speaker openings in the deck be large enough to vent through. Im sure I could build a 6 inch thick baffle to install any size woofer on the rear deck. But that would defeat the purpose of the install.

3 dayton ultimax 10's vs my MJ18 in 15 cuft. MJ 18 on 300 watts vs 600 watts on the daytons. (the mj18 xmax is 12mm so it actually runs out well below 300 watts)

Maybe three 10s or 12 IB on the rear deck could happen.

So as you can see here the rear deck is about 12 or 13 wide between the bracing. seat up (this color combo is kinda fuggly in some lighting, should have went with black interior lol) seat down, opening is about 27 inch wide at the bottom, 16 inches wide at the top, 30 inches wide in the middle, and 16 inches tall.

Turns out you can buy the steel back for $200 https://www.hondapartsnow.com/genuine/honda~frame~rr~seat~back~82126-t3l-a01.html

Ya that's right. Cutting the actual seat back. I would cut a small hole and let the sub vent into the seat foam. The problem with the rear deck is creating that baffle. The actual deck is <12" and I have to deal with the lid tension bars. I'll get pictures. Its useless to talk about this without showing you what it looks like.

I'll get some pics when I can. Here is a stock photo of the rear seat. As you can see, its one section. stock photo of the truck

I forgot to mention that the rear seat does lie down unlike other coupes I've seen. So I think its not structural, thoughts? The issue with the rear deck is that it's very narrow, roughly 12". Stock sub installed in the rear deck is 8 inches with two additional holes for 6.5" drivers. Current driver options that I own are my Mach 5 MJ18 and 12" AA Arsenal. Making the MJ18 fit in a car is rough, I'd probably grab a 15" IB sub option just save myself the hassle.

I would like to run an IB sub (ski pass) setup in my new vehicle (2015 honda accord coupe) but I'm unsure if its a smart idea to cut the rear seat back. In previous vehicles w/ a 60/40 split rear seat I would lay down one of the rear seat sections. However, this vehicle the entire rear seat back is steel and does not have a split section that I can lower. Also, there is no pocket arm rest in the center like most sedans which people commonly vent through. Can I remove a section of metal and vent through the foam/leather seat? For low frequencies I think I would be fine... How much metal should I remove? Some percentage of SD? Are there any safety concerns I should have when removing some of this metal? passenger safety? (who actually has passengers in a coupe I assume the function of steel is noise barrier and maybe some fire barrier?

Bonus points for any suggestions on used cars under 20k. So far I have test drove a 2016 accord v6 sedan and 2015 Q50.

I was meaning to update this post back at the end of fall. I finished the construction of the door enclosures and enjoyed them for last few months with some exceptions. Unfortunately the car is on its way out and I'm looking for a new vehicle. Below i'll post a few photos of the install as it (I actually removed everything today). Door Enclosures The door was cut back to allow some additional volume for the enclosure. I constructed the enclosure in a clam shell kind of shape. I used foam to create in the internal volume an shape. I dont have pictures of the shaping process and I'm not sure if I would do it this way in the future. Here is where I missed some photos. I used a piece of MDF to create a flat side to the outside of the enclosure and positioned the speaker baffle. The baffle was built with a replaceable ring so I could swap in other drivers (sls 8s are bit on the smaller side compared to other 8 inch drivers). The 2 pieces of the clam shell design where glued together with panel adhesive (the good 3M stuff). I dont have a photo but the enclosure are about 1/4" from the seat so I really maximized the volume. I had a little noise when using an analog rca connection with the c-dsp. so I grabbed a fio dac with a digital output. Pretty happy with the result. The crazy connector I have to use with my phone. I use an usb c extension so this whole thing doesn't hang from the phone. It retains phone charging. Just prior to Xmas I had one of the polk 2 channels pop (made pop sound on the speaker that was connected went into protect). I wasn't playing the system at the time so it was pretty strange. Found a hole in a voltage regulator. I replaced both of these chips and it booted up fine. Have not tried it on music yet. Hopefully I fixed it as these are great amps and put out a ton of power bridged. For some reason I started finding frost and a lot of moisture in general on the amplifiers in the trunk. I'm not sure what's causing it. It was not a leak, perhaps it was not venting? Anyways, apologies again for not posting more photos. Hopefully, I do a better job on the next car. I suspect I'll just install my set of SSA components, C-DSP, and PPI 4 channel initially and go crazy after buying a house with some garage space!

I'd encourage you to learn a bit of box modeling. Grab winISD and follow a tutorial to model your subwoofers. It should be very simple to compare the two setups you've had and see what the differences in their response.

knock down sealed boxes are decently fool proof if you can find one with the right cutout size or something close enough to work with some modification. You just have to glue it up. https://www.parts-express.com/cat/subwoofer-speaker-cabinets/289 some of these have a blank baffle so you would just need to borrow a jig saw to cutout the hole.

If you're just building this for the memes than use the 12", save yourself some money. It wont be louder or sound better then your standard enclosure that occupies the same space. As long as you're aware than have at it.

I'm looking at photos of the spare tire location and I think you could remove that foam piece that holds the tools and build a decent sized sealed enclosure for at least a 10" subwoofer for sure.

personally I would go with a subwoofer install in the spare tire well before trying out the pioneer option. You might be able to retain the spare if you're willing to raise the truck floor up a little bit. Getting creative with fiberglass might net you enough volume and depth for a 10" or 12" sub. optionally, remove the spare entirely and just swap the enclosure and spare for long trips where having the spare in the vehicle would be preferred.

can you like the exact enclosure you purchased? Unfortunately, subwoofers don't work well in just any enclosure and these prefab enclosure tend to make a ton of compromises to deliver a product at the lowest price. If you have to go prefab I'd recommend sealed enclosures.

you would wire them like below. Your amp has 2 sets of input terminals but its just a 1 channel (mono) amp. So those terminals on the amp would be in parallel. I would just wire as shown below.