4
Started tearing down, took the seats out and most of the body panels, rear deck, etc
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2017 Mustang GT - big infinite baffle 3 way...
2
So after my last car got written off (2015 Mustang GT), I managed to grab most of my gear before the insurance company took the carcass away... I replaced the car with a new 2017 GT also with the performance package, but i opted to go to the “premium” model with the stock 3 way audio and Sync 3 system in it. It’s been over a whole year now and shy of pulling off the really annoying stock tweeter grills, it’s been entirely stock and a whole lotta sucky in the audio department. Two young kids and a new homestead been keeping me busy and out of the shop but last weekend I finally caved and pulled an all-nighter to get things started.
Last time I had a single Sundown audio Z v.4 running through an infinite baffle between the trunk and the backseats. I sealed and dampened the back fairly well and I really did like the sound, but it lacked on the output side and if i really cranked it, the sub just didn’t keep up. So i did some digging, spent time researching different options for subwoofers this time around - I bought a pair of 15” JBL wGTI and was all excited until one of them showed up broken. After the debacle of trying to collect from Fedex (which I never did end up being able to do) - it lit a fire under me a bit and I got pissy so i went a bit overboard and jumped to my (then) second choice. Impulse buy later and two brand new Fi Car Audio IB3 18” woofers showed up - had to take my wife’s car to go pick them up from UPS, they wouldn’t even fit in my car, al least certainly not while still in their packaging.
So here’s the start of a new build, same Zapco LX 6 channel running my front 3 way - might change the dynaudio mids out for some AudioFrog GB25, but definitely keeping the GB10 tweeters and the Si TM65 mids. Using the same Zapco Z3KD for the new subs, and using the same miniDSP C6x8 - this time with some much better integration to the OeM system (more on that later).
For now, here’s what I’m starting with:
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Last time I had a single Sundown audio Z v.4 running through an infinite baffle between the trunk and the backseats. I sealed and dampened the back fairly well and I really did like the sound, but it lacked on the output side and if i really cranked it, the sub just didn’t keep up. So i did some digging, spent time researching different options for subwoofers this time around - I bought a pair of 15” JBL wGTI and was all excited until one of them showed up broken. After the debacle of trying to collect from Fedex (which I never did end up being able to do) - it lit a fire under me a bit and I got pissy so i went a bit overboard and jumped to my (then) second choice. Impulse buy later and two brand new Fi Car Audio IB3 18” woofers showed up - had to take my wife’s car to go pick them up from UPS, they wouldn’t even fit in my car, al least certainly not while still in their packaging.
So here’s the start of a new build, same Zapco LX 6 channel running my front 3 way - might change the dynaudio mids out for some AudioFrog GB25, but definitely keeping the GB10 tweeters and the Si TM65 mids. Using the same Zapco Z3KD for the new subs, and using the same miniDSP C6x8 - this time with some much better integration to the OeM system (more on that later).
For now, here’s what I’m starting with:
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4
6
Made a mock-up baffle using cheap osb - realized fitting two 18” subs is going to take some work...
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The baffle ends up coming from the bottom of the backseat on an angle upwards ending just shy of the glass - so i plan to deaden the panel, remove the rear speakers and fast-ring style the openings into the cabin using seating foam to also help keep pressure in the rear deck panel to avoid any rattles.
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I then transferred the template over to 19mm 13 ply void-free Russian birch, and added threaded inserts for the subwoofer mounting bolts:
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The baffle ends up coming from the bottom of the backseat on an angle upwards ending just shy of the glass - so i plan to deaden the panel, remove the rear speakers and fast-ring style the openings into the cabin using seating foam to also help keep pressure in the rear deck panel to avoid any rattles.
I then transferred the template over to 19mm 13 ply void-free Russian birch, and added threaded inserts for the subwoofer mounting bolts:
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12
Started the amp rack - attempting to do something similar, albiet a little more polished than my last build...
Last build looked like this:
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The trim panel covered with carpet/felt was ok, but I didn’t have a real solid mounting underneath and there was neither consistency nor really solid mounting point (the gap between amp and cover looked like this):
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(You can see through the gap above the top amp to see some of the wiring revealed/etc - also the wiring was too tight underneath)
So this time... I started with a better foundation; using rivnuts and machine screws along with construction adhesive I mounted three bricks on the flat even areas of the well, then I screwed rails on top of those, and ultimately mounted a 19mm birch plate after painting it all to avoid moisture issues:
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This time the whole base is even, level, and measured so that the top of the amps is even with the bottom of the trunk space.
Next I set to a better way to handle the spare battery mounting location, fuses, power wiring, etc. I created a false side using mdf - angled to also double as added bracing under the side edge of the subwoofer baffle too.
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(Pre-drilled the larger holes for 0/1 gauge cables)
Then i framed in a battery box using some more birch:
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Once the side was done i added a small strip to the top and used a 3/4” roundover router bit, then covered it in carpet before adding the fuse holders:
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The battery back here will remain somewhat hidden behind the panel, it doubles as a bit of an added power source but also a distribution block:
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Sent from my iPhone using Tapatalk
Last build looked like this:
The trim panel covered with carpet/felt was ok, but I didn’t have a real solid mounting underneath and there was neither consistency nor really solid mounting point (the gap between amp and cover looked like this):
(You can see through the gap above the top amp to see some of the wiring revealed/etc - also the wiring was too tight underneath)
So this time... I started with a better foundation; using rivnuts and machine screws along with construction adhesive I mounted three bricks on the flat even areas of the well, then I screwed rails on top of those, and ultimately mounted a 19mm birch plate after painting it all to avoid moisture issues:
This time the whole base is even, level, and measured so that the top of the amps is even with the bottom of the trunk space.
Next I set to a better way to handle the spare battery mounting location, fuses, power wiring, etc. I created a false side using mdf - angled to also double as added bracing under the side edge of the subwoofer baffle too.
(Pre-drilled the larger holes for 0/1 gauge cables)
Then i framed in a battery box using some more birch:
Once the side was done i added a small strip to the top and used a 3/4” roundover router bit, then covered it in carpet before adding the fuse holders:
The battery back here will remain somewhat hidden behind the panel, it doubles as a bit of an added power source but also a distribution block:
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8
I covered the backside of the baffle in the same carpet/felt and started to bolt everything down to the car. Using the factory M8 welded nuts to hold the battery/side panel down in place and pre-drilled some 3 inch #8 wood screws between the baffle and the side panel. (Not pictured, i did a similar inverse side panel on the opposite side screwed between the rear deck and the upper side of the baffle - that one using more birch).
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(Also glued carpeting down to the floor, stretched to cover the amp rack too)
Started wiring the power to the amplifiers, and then I screwed the amplifiers down to their desired positions. Up next is the dreaded door molex to run the speaker wiring - only so much time in one night though
so that’s gotta wait until tomorrow.
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(First time using wire ferrules - they were “oversized” a little too much so i cut them and then used my hydraulic crimper to tighter them on)
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(Also first time using techflex... i probably should have asked for some tips, feeding 20 feet through it sucks!)
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(Drilled a 1” hole through the firewall fom within where the battery box sits, used a rubber grommet after a quick shot of paint/primer to deter rust)
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(Mounted the front fuse holder and left a lead to connect to the main battery/charging system)
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(Re-installed the battery box, put the battery in it and connected up the wire to the rear - fused at 300amps)
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(All buttoned up and back to looking oem)
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(Also glued carpeting down to the floor, stretched to cover the amp rack too)
Started wiring the power to the amplifiers, and then I screwed the amplifiers down to their desired positions. Up next is the dreaded door molex to run the speaker wiring - only so much time in one night though
so that’s gotta wait until tomorrow. 
(First time using wire ferrules - they were “oversized” a little too much so i cut them and then used my hydraulic crimper to tighter them on)
(Also first time using techflex... i probably should have asked for some tips, feeding 20 feet through it sucks!)
(Drilled a 1” hole through the firewall fom within where the battery box sits, used a rubber grommet after a quick shot of paint/primer to deter rust)
(Mounted the front fuse holder and left a lead to connect to the main battery/charging system)
(Re-installed the battery box, put the battery in it and connected up the wire to the rear - fused at 300amps)
(All buttoned up and back to looking oem)
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4
So I’ve come to the realization that the baffle is too flimsy for my liking; adding another plate is not really an option given how awkward and difficult it would be to fit it in place... so, i welded up some brackets to a 1x1 inch steel tubing section cut to match the angle of the baffle. I drilled some bolt holes through it and will attach to the car chassis using 1/4x20 rivnuts.
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I painted the brace in gray, and covered the front of the baffle with a gray vinyl wrap. At this point I came to the scary realization that I have not actually tried to mount a woofer (or even check clearances) since i first made the baffle (which is at this point permanently affixed). It barely makes it after some awkward tweaking to get the motor through the speaker hole...
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At this point I’m also sure I will have less than a few millimeters of clearance between my brace bar and the two woofers - so before drilling the holes and mounting my brace bar I figure I’m going to have to mount both subwoofers in. So next steps are to remove the factory rear deck speakers, (that’s the intent anyways, but also because I need to be able to reach both sides to tighten the bolts on the brace to mount it). So this is where it sits as of now; still have to get back to wiring the source, miniDSP, and speakers - then installing and dampening the front stage/doors too.
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I painted the brace in gray, and covered the front of the baffle with a gray vinyl wrap. At this point I came to the scary realization that I have not actually tried to mount a woofer (or even check clearances) since i first made the baffle (which is at this point permanently affixed). It barely makes it after some awkward tweaking to get the motor through the speaker hole...
At this point I’m also sure I will have less than a few millimeters of clearance between my brace bar and the two woofers - so before drilling the holes and mounting my brace bar I figure I’m going to have to mount both subwoofers in. So next steps are to remove the factory rear deck speakers, (that’s the intent anyways, but also because I need to be able to reach both sides to tighten the bolts on the brace to mount it). So this is where it sits as of now; still have to get back to wiring the source, miniDSP, and speakers - then installing and dampening the front stage/doors too.
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Thanks
- just noticed your post looking for a Z3KD ... they’re a great amp! Can’t wait to get this one (re-)playing again...Sent from my iPhone using Tapatalk
I have Zapco AP6ch and I love it. So I would like to get a Zapco for my IB subs
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First gen - DVC
... 2 ohm drivers to the Zapco LX - if money wasn't an object I might be looking to replace them with some AudioFrog GB60 - but I was quite impressed with these before in nearly the same car.
This is my fifth Mustang now - second in this body style (both GT with performance package at that). I'm a tall/big guy - my kids are young (read: small) - I have a long-ass commute (106miles to work) ... so I *must* enjoy my ride else risk going crazy. At least that's how I justify to my wife
lol - all kidding aside though, great car - love having all the added room up front with a 2 door, even if at the expense of having to let my kids in/out of the backseat ... with my three year old that's actually a bonus (she can't open the door this way while driving). Everyone knocks the Mustang as a family car - to each their own I guess, but both of my kids came home from the hospital as babies in a mustang.
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