Can anyone throw out some ideas on how to mount my battery in a very tight space in my hatch next to my custom box? A battery tray is too big as I only have a about 7” of room.
Thank you for the idea! I was thinking all night about this. I think I might try to get the box as far left as I can and use two L brackets lengthwise to hold the battery from moving forward or backwards and then two more L brackets on each side of the battery but spaced just enough to fit j hooks and use a 6.8” battery hold down from advanced auto... the j hook on the sides and hold down should secure it up and down and side to side once tightened.
barely fit the enclosure I built lmao. 3500 watts RMS from a Skar rp3500 going to two Skar VXF 12”s. They’re rated 1500 watts rms conservative each sub! My car should be extremely loud. My kicker l7 was not enough for me so I went all out this time...
No internal bracing on the enclosure aside from whatever the slot port contributes...we shall see if there is noticeable resonance lol. It’s my first box build and I’m just happy the box is together and the subs fit lmao.
a box that large needs internal bracing imo. especially since its mdf. you want zero movement of the outside layers. i recommend putting put some vertical pieces of wood on the insides of the box.
if this is a photo of top down perspective, put some vertical pieces of mdf, like 4" wide or so, in the center of each interior wall. make sure to cover the entire height of the box. also include 2 sides of the port (not in the port itself). cut 45's on them so its not just a square piece of wood, it'll help smooth out airflow. also brace the bottom of the box if possible. either by a vertical dowel rod running from baffle to bottom, or another long piece of mdf that runs from the left side to right side
mounting amp to box is fine 95% of the time. vibration kills amps. the less your box flex's the less chance you'll have of breaking the amp.
first off, I would also strongly recommend adding a couple of small braces to the inside of that box. All of the following descriptions are based on the first pic of the sub box provided as we are looking at it. (height is from focus floor to ceiling, depth is from hatch door to front of car, and width is from left side of car to right. the "front" is the rear most edge up against the hatch door and the port runs from the back edge down the right side.) The way I would brace the box would be to cut three 3" strips to the exact internal height of the box. place one on the front edge running vertically up and down as close to center without being in the way of the sub (from the pictures angle, I don't think this will be an issue). Second brace would go on the left side, again as close to the center with out being in the way of the sub. the third brace would go alone in the inside of the back port panel, about one inch back from the edge. lastly I would get a 1" dowel rod, cut on piece to the exact internal height of the box and should be placed vertically right in the center between the subs, then cut two piece to the width of the port area (if your port is 20"x 4", then cut to 4"...) then place one horizontally inside the port between the outer and inner walls, one on the right side, dead center, and one one the back side, directly across from the brace in the previous bracing step. this should only take up about 0.09-0.11 cu-ft of air space which really shouldn't effect the speaker much if any, but this is why I never design a box at the extreme limit of the range of airspace unless I absolutely needed to fit it somewhere. but with subs that powerful, there is no way I would run it in a box with no bracing, especially having panels with that much area. and the small diameter of the dowel rod should not effect being inside of the port at all (either with volume or wind noise).
second off, No, I do not think that there would be an issue gluing another board to the outside of the port and mounting the amp to that.just remember, if you are using rubber washers/spacers, you need two for each mounting screw. one below and one above the amps mounting lip.
the detail you two are providing is amazing and highly appreciated! I’m sorry this is my first box build and I maxed out the hatch area for what I was comfortable with, but obviously the subs needed more room than I could provide.
Gotta learn the hard way I suppose.
I should be able to stuff those pieces inside the sub holes and fit accordingly. I am taking off work tomorrow to try to finish the box. I will take vids/pics. I had a feeling the box wasn’t sturdy enough for what I was doing.
Would you guys maybe at this point suggest seeing if I have enough clearance to roof to mount the subs inverted to free up airspace for the internal bracing? I would hate to mess up the mounting and ruin the sub surround by chafing it off of interior and of mounting holes if inverted.
Also I see from the diagram that you have the pieces of 3” mdf perpendicular to the walls. Disregard that question sorry. I was just confused because the other individual suggested parallel.
the air space lost by the bracing shouldnt really affect overall performance. might raise tuning up 1hz.
typically you'd want to do a flush mount for inverting the subs so you can center it better. but theres no issue with how it currently is so long as it is centered properly.
I like to see the excursion so I think I will mount them regular if they won’t be affected that much by the bracing. I will hopefully be finishing it up tomorrow and will post pics of the process.
Well, this might be one of those boxes only the builder can love...hahah not pretty at all, but I got the bracing in. I kinda had to hybrid between both your ideas to get it to a.) fit in this setup and b.) allow me to secure while the box is already assembled. This is my first box and first time using these tools so go easy on me. I tried... lol. Tomorrow, I’m gonna try to mount the amp to the amp rack, mount the subs, and hopefully get it in my car to hear it. I’ll still have to get some pieces of wood to wedge the battery in place but I can’t really do that til the box is in it’s spot.
Pretty sure I somehow managed to ruin the surround where it glues to basket. The screw went underneath the surround?? It’s not the only one that did that either. I’m still gonna run it see if it lets loose. What do you guys think about that ???
I had the same issue when installing my speakers. I used 12 inch MDF speaker rings spacer. Make sure that it fit around the OD of the surround and put chamfer all around The inside edge. Then I screwed that down with the speaker holds the surround to the basket.
Also, thank you for the compliment gheinrich. I don’t think that’s possible w this model sub because there is a lip on the far edge of the frame where the gasket kinda grips on. So it’s pretty much tear the sub apart and re glue it back together, or run it like this I guess.
Sorry I meant to say I put the chamfer on the outside diameter over the speaker ring so that it would crush down on me surround and clear that lip on the frame.
Lol I’m kinda frustrated about this. I’m gonna back the screw out and try to see if it will screw over top of that part of the surround. Such a stupid thing to happen.
Honestly I've had tears in surrounds before and I just use a little black RTV. And maybe some type of small washer. Then you want a slight radius or something on it so the washer doesn't dig into the surround. The best that I found is using speaker ring over the top of the speaker. Clamps the whole surround directly to the basket.
Well guys she’s in fits like a glove and sounds excellent too! I kinda had to finish it this weekend so she’s in with no carpet and the surround how she is. Still slams and I’m not even turning it up yet for the “break in”. I ran out of black 1/0 so red ground it is!
Finally got a chance to make a small video of the new build today.
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