To cut or not to cut... Hide a Sub

[sam.basye]

I built a 8" sub mount to fit in the driver's side cargo area body paneling. It fits perfect and really happy with how it all turned out.

The only opening is the little cabin vent in the plastic body panel; which sits just below the sub.

I originally planned to cut a hole in front of the sub and put a mesh cover on it, but, that's irreversible and I really like the hidden aspect now. Lol

I get some slight vibrations, but mainly only with the bass booster turned on above 0. With the booster on, it sounds like crap, at 0 it fills the back of the car nicely.

Soo, how much more "thump" and how much will the quality improve if I were to cut a hole in front of the sub. I assume there would be less vibration as well? Just trying to justify if it will be worth it or not.

Keep in mind: no hole = wife still won't know it's there. Lol please factor this into your suggestions

 

[JWaldz]

With the sub directly behind the panel like that, regardless if there is a cutout or not it will continue to rattle. Maybe not as bad with a hole but it will still do it. It's also doing it b/c the sub is drawing it's air flow from all around the back of the panel. You will get better bass and less rattle if you completely box it out, making an actual enclosure. Otherwise, good job with the stealthiness of the sub.

 

[gamefreakgc]

I built a 8" sub mount to fit in the driver's side cargo area body paneling. It fits perfect and really happy with how it all turned out.

The only opening is the little cabin vent in the plastic body panel; which sits just below the sub.

I originally planned to cut a hole in front of the sub and put a mesh cover on it, but, that's irreversible and I really like the hidden aspect now. Lol

I get some slight vibrations, but mainly only with the bass booster turned on above 0. With the booster on, it sounds like crap, at 0 it fills the back of the car nicely.

Soo, how much more "thump" and how much will the quality improve if I were to cut a hole in front of the sub. I assume there would be less vibration as well? Just trying to justify if it will be worth it or not.

Keep in mind: no hole = wife still won't know it's there. Lol please factor this into your suggestions

First off, if you make a habit of hiding things from your wife you're not going to have a very happy marriage.

Secondly, it needs an enclosure. You essentially have an open air sub since the plastic paneling makes a very poor enclosure. This is more important than an opening, since a lot of people run subs in compact cars in the trunk, so the seats basically "block" the subs but you still hear them just fine (although the cars behind you hear them more...). Some sound deadening or at least some of that rubber roofing materials on the back shell of the panel will go a long way too.

Third, do you have an amp? Subs sound terrible without one.

 

[MaxLine]

First off, if you make a habit of hiding things from your wife you're not going to have a very happy marriage.

Secondly, it needs an enclosure. You essentially have an open air sub since the plastic paneling makes a very poor enclosure. This is more important than an opening, since a lot of people run subs in compact cars in the trunk, so the seats basically "block" the subs but you still hear them just fine (although the cars behind you hear them more...). Some sound deadening or at least some of that rubber roofing materials on the back shell of the panel will go a long way too.

Third, do you have an amp? Subs sound terrible without one.

I second that an enclosure would make it sound a lot more clean. I would just add either way you should cut it if you think you can do it cleanly. Maybe get something to line the plastic so it doesn't look rugged.

 

[Renton4runner]

Yah, you need a enclosure with the sub. No one plays subs open air because they sounds like crap that way. I am partial to a sealed box, but to each their own.

 

[sam.basye]

I built it knowing there would probably be some rattles/vibrations. Since I bought a new head unit, I figured might as well go all the way and install an amp and sub while I was at it. The factory sub in my wife's MDX made me want one. Lol

I do have an amp; which is mounted under the driver's seat

I thought about boxing it, but as you can see, it's a pretty tight fit. I estimated that there is probably about 1 cubic foot of empty space behind the cargo panel, but nothing is sealed.

There's only about ¼" gap behind the magnet and the outer body panel.

I like the rubber weather striping idea.
I also thought about using some spray insulation foam. Not to be sprayed on the plastic body paneling, but the various gaps and open spaces between the sheet metal.

This is my first amp/sub install so I'm still learning as I go. I know an enclosure is ideal, but I figured what I've got was worth trying out. It doesn't sound bad unless the bass booster is turned up, but it could definitely hit harder with the right design.

I feel like I'm ⅔ of the way there, just need ideas for the last ⅓!

 

[gamefreakgc]

I built it knowing there would probably be some rattles/vibrations. Since I bought a new head unit, I figured might as well go all the way and install an amp and sub while I was at it. The factory sub in my wife's MDX made me want one. Lol

I do have an amp; which is mounted under the driver's seat

I thought about boxing it, but as you can see, it's a pretty tight fit. I estimated that there is probably about 1 cubic foot of empty space behind the cargo panel, but nothing is sealed.

There's only about ¼" gap behind the magnet and the outer body panel.

I like the rubber weather striping idea.
I also thought about using some spray insulation foam. Not to be sprayed on the plastic body paneling, but the various gaps and open spaces between the sheet metal.

This is my first amp/sub install so I'm still learning as I go. I know an enclosure is ideal, but I figured what I've got was worth trying out. It doesn't sound bad unless the bass booster is turned up, but it could definitely hit harder with the right design.

I feel like I'm ⅔ of the way there, just need ideas for the last ⅓!

The spray foam doesn't work too well. In another vehicle I put speakers in I tried to "seal" the rear cab wall to make an enclosure and didn't make much of a difference. Sheet metal just makes for a terrible enclosure for speakers or subs. I didn't pay much for the speakers so I didn't mind it and I had no amp.

Here's some food for thought from my sound overhaul in my 4Runner and some pics on how I sound proofed the rear: http://www.toyota-4runner.org/3rd-gen-t4rs/203866-thinking-about-upgrading-your-sound-system-do.html

 

[IsaiahC]

If you want to minimize used up cargo space, then I would cut the hole, mount a nice mesh cover, then push the subwoofer out as far as possible in order to make space for an enclosure. That would probably maximize sound quality while keeping the sub out of the cargo area. However, if you want good sound quality, ditch the hidden mount and make an enclosure that angles with the back seat. I have a 12" vented sub in the back and it sounds really good, even without the proper amp. With the proper amp, I feel you could get away with an 8" or 10" in an enclosure in the cargo area.

 

[sam.basye]

Thanks for the link gamefreak.

The whole hidden sub concept was an after thought, so I'm relatively pleased that it even works and I did everything correctly. Lol

Pretty neat feeling the cool air pulsing through the little vent when the sub hits.

I was testing out the radio functions and found that both the Bluetooth and aux input music sounds much better than the radio as far as sub sound quality goes... Less vibrating and hits a little harder.

I'm going to look into boxing it, if possible, and using some rubber trim on the backside of the plastic paneling.

Sometimes I use the cargo area with seats down and don't want to have to move a sub box around.

 

[sam.basye]

I went and bought some foam weather stripping and stuck it around the rear side window and inside the big plastic body panel. I also used some foam insulation - didn't seal all of it, but did most of it.

Definitely made an improvement. In the quest from without the added material to present state to sounding perfect. I'd say it made a 50% improvement. I can turn the bass booster to half way and it sounds good, unlike before. Might try to foam the rest of the gaps to seal it. No more vibrations.
I determined building a box would be too difficult and not worth it.

 

[nobb]

That's definitely not the proper way to install a sub. By coupling the sub to the vehicle structure, it will be next to impossible to fix all the rattles and the time spent doing so, you could have just built an enclosure. It will also be especially annoying because you might fix a certain rattle at a particular resonant frequency, only to develop a new rattle at a different frequency.

Also, without a proper enclosure, the output from the sub will be reduced drastically due to the back waves cancelling out with the front. Lastly, if the sub isn't rated for open air, it's maximum power rating gets derated because it will bottom out easier.

 

[sam.basye]

Like I said before, I wasn't looking for a concert every time I turn the radio on, rather a little extra thump and sound to fill the empty cargo area. The way I built the sub mount, I didn't lose any cargo space and it's a 100% clean install. There's no way to tell it's modified, which is exactly what I was going for.

I have little to no rattles with the setup and the output quality is pretty good considering there's no real enclosure.
I had my doubts when planning the project, but decided it would be worth trying.
I went into the project knowing nothing about subs or amps and this has helped me learn some basics.

I may try to use the form weather striping to create a seal leading to the vent, but not sure how to do it yet. That way the front and rear of the speaker and separated a little better.

I don't expect a lot from a cheap sub/amp combo, but overall I'm satisfied and wouldn't hesitate to do it again.

 

[sam.basye]

Update:

So, yesterday I decided to go at it and try one last time to make the sub sound better.

Jackpot! Lol
Sub sounds 10x better, hits hard, and is very clean without any rattles or vibrations.

I didn't do anything to the sub itself or the "enclosure".

I pulled the radio out to look at where I had the RCA jacks plugged in from the amp. Note looking at the lame diagram on the back of the radio, I started moving the plugs around (with music playing - probably not the brightest idea..)



Looking at the diagram, there's only one jack for a subwoofer.. Not sure why?
Anyways, I have two RCA plugs (left and right from amp), therefore, I figured I should use the left and right output jacks instead.
I ended up having one plug in the right output and one in the left input on accident.
This basically turned the sub into one big crappy speaker with the sub hitting in the background. It also made it so that the sub was linked to only the right rear speaker.. (reason why I pulled the radio again to see)
This also caused some vibrations and distortion.

I decided to plug one into the sub jack and it was a night and day difference. It didn't matter which plug was plugged into the sub jack or what the other was plugged into, or not into.

I then set the gain, low and high pass, and bass boost settings accordingly on the amp and now have crisp clean hard hitting bass that's completely hidden in the paneling and doesn't vibrate or rattle!


Can anyone explain why there's only one sub jack on the back and how you would plug in the RCA from the amp to the head unit? The amp has a left and right input.