My Sub Build (Ongoing)

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jmtiseo

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Well I've been real busy with work but I'm going to squeeze a thread in here about my upcoming sub build. It took me about a good two weeks of planning the box but I figured since I got it finalized I can start a thread.

Just going to say this is not going to be too extensive like other sub builds on here, especially the one where he goes through the "big 3 upgrade". Just wanting to share what I'm doing. This isn't a compare and contrast session. There's many different subwoofers, amps, and people out there. I've been pleased with the Image Dynamic brand, and my brother's been pleased with the Kicker Amplifiers.

Current System:
  • Two Image Dynamic's iD 12's
  • Kole Audio QX-1920 Class AB Amplifier (Can't find a spec sheet anywhere for this but it's been working mighty fine)
  • Polk Audio Door Speakers, stock center channel, and rear deck lid woofers.
  • 2.0 cu. ft. net ported box (30.5"x13.5"x24"), 3/4" MDF, tuned an estimated 32-36hz (Need to measure my ports to clarify)
  • Stock Head Unit/Radio/Reciever

IMAG0071-1.jpg


IMAG0073-1.jpg


IMAG0074-1.jpg


This thing pounds but I'm looking to gain a little clarity, an update, and just a wee bit of trunk space. This system has been with me since I was about 17, now 22. My brother had it a couple years before I did so I'll call her ol' reliable.

Up Next:

Subwoofer Enclosure Plan:
As I mentioned before it took me about two weeks to come up with the plan for this box. I ran it through WinISD (An enclosure design software) and Torre's Box Tuning Calculator found through this forum. With the design below WinISD, with the sub's specifications, says my box will be tuned to 30 hz, with a vent mach of .05. From what I've read, port noise (chuffing) becomes audible at a vent mach around .1. This is caused by turbulence within the port, and is why I am rounding the edges of my port to help prevent any.

This is all from, in my opinion, mind boggling research. It's much easier to throw a subwoofer into a sealed box but I like the challenge of doing a ported enclosure. I could have saved a shitton of space doing a sealed enclosure but each type, ported and sealed has their advantages as well as disadvantages. I believe I've done enough homework thus far to go with a ported design that is shown below. It's not the most detailed print but it does the job.

ImageDynamiciDMaxEnclosurePrint.jpg


Some concerns:
  • Of course the abuse on my electrical system asking for 1000 watts of RMS.
  • Porting a box decreases the power handling of the driver (so I've read) and may damage the subwoofer. For this reason I'm going to start by wiring it to 4ohm and 500w RMS to see how she handles and break her in. If I like this result I may just leave it hear knowing that I should be able to run it like that all day long and it's a lot less strain on my electrical system than my current one.]
  • Clarity, I'm running this off of a line out converter until I get said double din.
  • Port Noise (Chuffing)
  • Miscalculation causing my box to be tuned to high or too low.
  • My woofer grilles will not be tall enough for the excursion of the iDMax. I like the look of these and they're discontinued Kicker G12 Subwoofer Grilles. It's unfortunate that one of them snapped because a friend of mine broke it while helping me lift it.

Looking to start next weekend over the holidays.
 
Not as extensive! That looks pretty extensive to me! Your deff doing the right thing by building your own box. Makes the project fun. Everybody likes different brands and all have their strenghts, so sticking with what you like and are comfortable with is good.

Will be tuned in and good luck.
 
Got into the groove of typing and it all just so happened to be at the right place at the right time. I'm stoked about it.
 
Hey where do you plan on mounting the amp? I know I left that out on my original plans and havnt found a good location with my configuration.
 
Looks good, however you don't need 2 aeroports... That is waste of material/space.


Also port noise is pretty non-issue in a trunk setup, but aeroports don't have noise anyways. You can probably shave down the size just a bit and salvage some trunk space.
 
i love meade's site....one of the best audio forums in my opinion and build looks like its going to turn out great
 
FrankLS said:
Hey where do you plan on mounting the amp?QUOTE]

I won't know tfor sure until I get the box in the trunk. Currently it's mounted on the box as shown which I don't mind, but it's not the greatest. I'd like to possibly make a board to go over my spare tire and battery to screw it to. Which reminds me , where is the vent for an Optima Red Top? I've read it needs to be vented but for the life of me I can't find anywhere to attach a tube to it.

Andrizzle said:
Looks good, however you don't need 2 aeroports... That is waste of material/space.

Also port noise is pretty non-issue in a trunk setup, but aeroports don't have noise anyways. You can probably shave down the size just a bit and salvage some trunk space.
Click to expand...

I looked into Aeroports and they would be perfect but for modeling and calculations I found it easier this way. In terms of space either way I'm not going to be able to open the spare tire cover with the box in there. My brother has the same set-up but tuned to 34hz using two ports. I would have went with the single port but he mentioned he tried it once and it didn't sound right so I'm taking his word for it on the port issue.

Thirdworlddoug said:
i love meade's site....one of the best audio forums in my opinion and build looks like its going to turn out great
Click to expand...

I found that calculator and I'm like woh! Things just got a whole lot simpler. Then I realized that a couple of things were off in the program. I don't think it includes the port as a solid object (OD of 4.5") when calculating volume. If it did then I screwed up somewhere in my own volume calculations. I also got some assistance from my thread on DIY Mobile Audio.

I know you can only get so much from a youtube video but here's a 10" idMax doing work. 10" IDMAX - "Put On" (bass line)
Click to expand...
 
*Edit on first post - My current box is tuned to right around 35hz.

Got the goods over a week ago but I just got to comparing them and posting up on this.

So excited to start this build next Friday. Here's a shot comparing Image Dynamic's iD 12 to 2 cans of Coors Light because Bud Light don't pay mean then the idMax. The idMax weighs around 36 pounds, by feel it's about 2-3 times heavier than the iD. Here's a pic. I didn't really get the size of this until I compared it to the one I have. Not the largest, but it's a bigguns.

IMAG0109.jpg


My sub/amp combo.

IMAG0111.jpg


I was a nervous setting these two this close to my computer but all is well. Didn't get too close.
 
Those kicker grills are nice. I've got one covering my Alpine type R in my trunk. I wouldn't mind reworking my setup to include a ported box for more SPL but don't really have the tools to put one together properly.

I've been messing with WinISD for a while trying to decide on what to do with my other type R (been in the closet for about 6 years). Also been looking into a SonoSub but am having trouble getting that one past the wife :D Don't yet have the home theater setup to necessitate a home sub.... One day.

Have you considered a slot port instead of the two round ones? I ask because adding a slot port makes for a stronger box than one with two holes cut in the sides to insert the ports. You could get about the same area using a 2" slot port (full height of the box), then adjust the length to maintain your tuning. This would also give you more clearance between the back of the woofer and the port walls.
 
They are the nicer grilles that i've seen lately. A lot of the new ones that are out there just seem cheesy. I'm thinking about painting them but considering nothing else is color matched to the car that it wouldn't look right.

I've thought about doing a slot port but once you build the slot it's difficult to next to impossible to retune it without tearing the whole box apart. I'm thinking about adding a piece to the inside of my box to support the other end of the ports because they're quite long. This will add bracing while supporting the pipes. Also, air travels through something round rather than square I think. and if I went with a slot port it would need to be ridiculously long if I remember right.

Bracing is not really my concern and I haven't come across a system that's had it or needed it. If I had a high output 15 I might look into it. It's not hard to add either for me.
 
jmtiseo said:
I've thought about doing a slot port but once you build the slot it's difficult to next to impossible to retune it without tearing the whole box apart. I'm thinking about adding a piece to the inside of my box to support the other end of the ports because they're quite long. This will add bracing while supporting the pipes. Also, air travels through something round rather than square I think. and if I went with a slot port it would need to be ridiculously long if I remember right.
Click to expand...

You are correct about re-tuning the box after the build. It would be nearly impossible with a slot port. Easier with tubes you can cut or replace with longer ones if necessary. You could even make one that is adjustable to play around with.

Not correct on the length of slot port though. If you look at the open area at the end of the port, that is what controls the length for a given frequency. So two 4" round ports = 25 in^2 the same area as a 2"x12.5" slot port so the length of each would be the same to produce the same frequency.
Since the slot port does have slightly more perimeter (15%) than the two circular ports the air would move more freely through the circles, but that is more advance fluid dynamics than is typically necessary in box building.

But it is your box after all...

Where do you plan to mount your amp? On top of the new box like the old one?
 
Completely understand what you're talking about. Let's not bring in fluid dynamics into discussion here lol. I only have to go up to calc. I in my studies, I can't even fathom the complexity of fluid/thermo dynamics.

Anyways, I went out there yesterday with amp in hand. I'm still unsure of where I'm mounting it but from what it looks like it will need to be on the box. A part of me doesn't want it in the spare tire well. Maybe mount it on top or back of the box or mount it to the rear seat.
 
Looks like the sub will pound.

Keep us updated and be sure to break it in for a week or two before you really beat on it.
 
I would recommend not mounting the amp on the tops of boxes, hot air rises and at the top of the trunk, there is no where for the heat to escape to, and it will always be bathing in its own heat. this will eventually shorten the life of any amp.
 
Actually from the my limited experience, port noise is highe with a circular port than a slot port. That is the only reason I went with port. Just ask pektel. I remember him mentioning how loud his circular port is. The slot on my box makes virtually no noise. Just a slight whooshing noise. Ill put up a video tonight.

Build sounds great though. I like your plans.
 
I plan to break it in. Nothing too serious for a couple weeks. I might wire it to 4ohms so it's only getting 500 watts as well. This amp shouldn't heat up much if at all from that.

I might wrap a board and mount it on the sides somehow. I understand the heat concern. If all else fails it's going on the back of the box. Sometimes I need my seats down and I don't want the amp all out in the open being vulnerable to me putting stuff back there.

As far as port noise, it is a concern but I think if I have any then I'll round the edges of the port. If I still have some after that then I just hope it won't be audible in the car as mentioned before in the thread.

I'm now tossing around the idea of doing the "big 3". If I don't do it now I won't be able to do it until next August as I don't have the resources to do it where I'm at now. Figured do it right the first time and if the lights keep dimming then upgrade the battery and alternator.
 
Here's a shot of my setup for what its worth:

vbpgimage.php


I'm running 300rms to my sub and 300rms to my interiors with a cap but no "big 3" upgrades. The stock battery has been good to me for the past 6+ years. Only minimal dimming of the lights when on full volume at low rpm.

Port flaring is always recommended whether circular or slot port. Port noise is a function of air velocity. Larger ports need longer length for the same frequency tuning... but smaller ports produce greater air velocity. Rule of thumb, anything above 10 m/s reported port velocity will produce chuffing (bad). Thus the balancing act between available port length and allowable air velocity for a desired tuning frequency.

Your amp should not have any heat problems at 4 ohms so just mount it somewhere out of the way (just not upside down on the rear deck). Access to the spare tire well is always desirable, but I've honestly only needed the spare once in over 6 years.
 
jmtiseo said:
I plan to break it in. Nothing too serious for a couple weeks. I might wire it to 4ohms so it's only getting 500 watts as well. This amp shouldn't heat up much if at all from that.

I might wrap a board and mount it on the sides somehow. I understand the heat concern. If all else fails it's going on the back of the box. Sometimes I need my seats down and I don't want the amp all out in the open being vulnerable to me putting stuff back there.

As far as port noise, it is a concern but I think if I have any then I'll round the edges of the port. If I still have some after that then I just hope it won't be audible in the car as mentioned before in the thread.

I'm now tossing around the idea of doing the "big 3". If I don't do it now I won't be able to do it until next August as I don't have the resources to do it where I'm at now. Figured do it right the first time and if the lights keep dimming then upgrade the battery and alternator.
Click to expand...

Mounting the amp on the sides is deff an idea. There is some room even with the trunk "arms" rotating in. Having an amp just in the open is not very smart. Thats the set up im running right now :D.

I dont think port noise should worry you much. Even if loud, like you said, i highly doubt it being loud enough to be heard inside.
 
We shall see on mounting the amp on the sides now. The driver's side has more room for one, unfortunately when I went to park my car and take a look in the back trunk to re-analyze the space situationg my carpet is wet back there. I just had a car wash so I'm thinking maybe my rear gasket is bad around the trunk opening. I remember opening up the spare tire well and I do believe IIRC there was water down there, but I could be seeing things.

Anyways I can't wait to start this when I get back home. @FrankLS nice video, I see the problem you're having with mounting the amp. I'd like to shoot a video too but I don't know how well the Evo 3D can pick up the the lower frequencies and the subs movement. I'll give 'er a try before taking out my old system.
 
Thanks, im using the Epic 4G and the camera sucks!

Take my advice, figure out your amp location before you build the box. Youll be kicking yourself in the face afterwards.
 
My box build will allow me to put it behind the box. I believe yours is flush up against the seat right? I have probably a good 8-10 inches behind my box right now with it pushed all the way back. The opening gets a little tight back there (giggity).
 
A quality amp won't get very hot and even if it gets warm it won't fail. My AQ amp has been solid behind my seat even in the 125 degree texas summer.
 
I don't plan on having a heat issue. I've probably mentioned it before but my brother's ran the same setup now for 3 years on the same amp at 2 ohms. Not worried at all in that aspect. If something does go wrong I'll send it in to get fixed.
 
n8bachelor said:
Here's a shot of my setup for what its worth:

vbpgimage.php


I'm running 300rms to my sub and 300rms to my interiors with a cap but no "big 3" upgrades. The stock battery has been good to me for the past 6+ years. Only minimal dimming of the lights when on full volume at low rpm.

Port flaring is always recommended whether circular or slot port. Port noise is a function of air velocity. Larger ports need longer length for the same frequency tuning... but smaller ports produce greater air velocity. Rule of thumb, anything above 10 m/s reported port velocity will produce chuffing (bad). Thus the balancing act between available port length and allowable air velocity for a desired tuning frequency.

Your amp should not have any heat problems at 4 ohms so just mount it somewhere out of the way (just not upside down on the rear deck). Access to the spare tire well is always desirable, but I've honestly only needed the spare once in over 6 years.
Click to expand...

Thats a nice setup i may do something like this for my next build.
 
I probably have about 1 1/2 in of room between the backseats and the box. I was shooting for taking all the available space and still allowing for access to the spare. I did just that, but no room for amp.

If I had a side port, I could probably mount it up front, but I like keeping a clean setup and want to hide as much s possible.

Like Black said, any good amp shouldn't get hot. I know my amp has never gotten past slightly warm. Very slightly, almost hard to tell. I don't think you should have a problem with overheating.

One thing I was thinking about was if the box extends past the factory "crease" on the floorboard and does not allow the floorboard to rise and have access to the spare, we should be able to cut the hollow backing on the floor panel and create a new "crease" where he new box ends. Kind of confusing, hope u understand.
 
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