2002 Toyota Tundra Access Cab - center console sub

[keep_hope_alive Premium Member]

I've been building a system for my brother in-law for a while now. working on it when he brings it over. family is free - beer is usually provided.

this one has been interesting and a fun challenge.

Equipment:

Alpine IVA-W200 head unit

MTX TA5302 at 2 ohm stereo

MTX TA5302 at 4 ohm bridged

Ultra 10" sub

Image Dynamics CX62 NX30 component set

Wiring - Streetwires, AudioQuest, Monster Cable

Security - Viper (no pictures will reveal any aspect of the alarm system, just know that you won't find what you need in time to disable it.)

we started with the center console sub enclosure

3/4" MDF was used for the entire enclosure. A double thick front baffle was used to recess the Ultra 10" and provide additional strength. The enclosure was sealed with wood glue and clamped. then, i mixed MDF sawdust with wood glue to make a paste that i spread on every internal seam.

two internal braces were added to prevent any settling over time and add additional strength. the end result inside the enclosure isn't beautiful, but it sure is strong.

the truck was pretty resonant, so a layer of the cheap stuff (Fatmat) was an inexpensive way to help add some mass to the floor and tranny hump where the sub would play. we did three layers on the top and sides of the tranny hump, and one layer over the entire rear floor. this pic is about 30% complete.

this was a typical end result

a layer of carpet padding went down to help decouple a layer of thick vinyl to block road noise. we ended up removing some of the vinyl and padding where the seat mounts go.

Click to read more...

 

[keep_hope_alive Premium Member]

The factory doors have massive openings. covering and sealing these was a decent amount of effort.

outer door skin was deadened around and behind the speaker and some polyfill padding was siliconed to the outer door skin behind the driver. i've done this in several other vehicles with no issues of water retention and great midrange benefits.

Melamine panels were siliconed and screwed to cover the openings. then deadener sealed over them.

the Image Dynamics CX62 midbass drivers were very deep. I modified the factory mount to maintain the correct angle with the door, then used 3/4" MDF spacer and rubberized foam to help isolate each surface from the other. finally, deadener was used to seal it all up from the inside.

 

[keep_hope_alive Premium Member]

driver side door is done the same way.

we also used carpet, foam, and polyfill to fill any gaps between the door panel and deadened skin. the result is ZERO rattles or buzzes.

battery also received initial attention. it will soon be replaced with a new AGM battery and better posts used. we upgraded battery-chassis and engine-chassis grounds.

used grommets through the firewall for both 4awg and 10awg.

 

[keep_hope_alive Premium Member]

head unit installed, we used some "special tricks" to make removing this a complex process.

here we were testing tweeter locations with trusty velcro until we finalize a placement. there are now flush mounted in this location, but i realized i don't have pics of them.... doh!

this was a temporary location for testing. we ended up with a down firing orientation and the performance was MUCH improved

everything had functioned great for a year or so, but I wanted to take a second look at the amps. turns out, one will fit in the rear seat storage (passenger side). this allowed us to move the fuse holder and ground distro block to the driver storage compartment, and this in turn, eliminated wiring under the seat. should have done this in the first place.

anyway, i made a new false floor for the single amp. now at least one back seat passenger gets more leg room. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif it is held in place with the driver's seat - works great and has been nice for my bro to have a larger flat surface for his tools. no one sits behind him anyway - he's a tall bastard.

fiberglass center console coming soon!

 

[keep_hope_alive Premium Member]

revised center console was installed.

the storage compartment was mounted and combined with the enclosure.

the loading board was removed and angled feet installed to hug the tranny hump.

a grill was added for general protection. an EQ was added in the storage compartment.

the sub amp was installed in the rear passenger storage compartment.

 

[legendndisguise 10+ year member]

Whenever you want to stop through MD, you can work on my car.

Good clean work as usual.

 

[keep_hope_alive Premium Member]

thanks.

this is a budget setup. gear was purchased used except for teh sub. the sub was the same cost of the HU, speakers, and amps! it sounds **** good.

i realized you can see the apillar tweeters in the second to last picture.

you may notice the original plans had the sub facing back. after testing back vs. down, down was the hands down winner. and down without a dedicated loading board was also a winning configuration. luckily, the stair-step design worked in both orientations. i have many more pics of this build on my PC - especially pics of teh sub enclosure. i now notice quite a bit is missing.

it should look pretty good when done. the factory center console was the same size as one for a Camry. WTH?

 

[perfecxionX 10+ year member]

i've done this in several other vehicles with no issues of water retention and great midrange benefits.

could you elucidate on this?

 

[keep_hope_alive Premium Member]

could you elucidate on this?

sure.

adding an inch or two of absorption behind the speaker won't do much for low frequencies, but you get some break-up of the rear wave and some absorption (minimal) of upper midrange frequencies. how much absorption depends on the material used, its density, and it's thickness. just as polyfill provides some benefit in a sub enclosure, the stuff i used in the pic above is much dense than the stuff you buy in bags (and was in a large sheet). midrange frequencies are what suffer when you have a hard reflecting plane right behind the driver (concave) since the distance from driver to wall and back causes phase cancellation in midrange frequencies. you want to weaken the rear wave reflection, break it up, so it doesn't come back to the cone. adding absorption in the corners of the door cavity would provide some low frequency absorption, but behind the woofer is a minimalistic approach. with vs without is noticeable and with is preferred. it's an easy test to try for yourself. it's similar to the premise of deflex pads.

my next experiment will be replacing that with PVC encased fiberglass batt that is compressed. in architectural acoustics, we use pvc encased fiberglass (around 1pcf) in banners to add absorption in pools and gyms.

 

[keep_hope_alive Premium Member]

note that i would prefer quadratic-residue diffusion with absorption in the nulls over just absorption. I may work on something like that if i use doors again in my accord.

 

[perfecxionX 10+ year member]

sure.
adding an inch or two of absorption behind the speaker won't do much for low frequencies, but you get some break-up of the rear wave and some absorption (minimal) of upper midrange frequencies. how much absorption depends on the material used, its density, and it's thickness. just as polyfill provides some benefit in a sub enclosure, the stuff i used in the pic above is much dense than the stuff you buy in bags (and was in a large sheet). midrange frequencies are what suffer when you have a hard reflecting plane right behind the driver (concave) since the distance from driver to wall and back causes phase cancellation in midrange frequencies. you want to weaken the rear wave reflection, break it up, so it doesn't come back to the cone. adding absorption in the corners of the door cavity would provide some low frequency absorption, but behind the woofer is a minimalistic approach. with vs without is noticeable and with is preferred. it's an easy test to try for yourself. it's similar to the premise of deflex pads.

my next experiment will be replacing that with PVC encased fiberglass batt that is compressed. in architectural acoustics, we use pvc encased fiberglass (around 1pcf) in banners to add absorption in pools and gyms.

i was actually aware of all that, the reason i asked was because i was under the impression that polyfill was not a material that would really offer any of those reflection dampening benefits in the mid frequency range. In the past when ive built cabinets for the home i use owens corning 703 (i think) which is not too easy to find or very cheap. Where do you find this denser polyester material you use? because i just finished some pillars that have a 3" midrange driver IB, and would like to put something behind it but the owens corning is too rigid.

 

[perfecxionX 10+ year member]

also, while we're on the subject of reflection dampening, ive been looking at purchasing a dash mat because the design of my dash panel is such that its pretty obstructive and likely causing alot of reflections. I was looking at buying a dash designs sedona suede mat, but on their website it says:

Quoteo Dash Designs® Dashcovers have openings for the speakers on my dashboard?

No, all of our dashcovers are constructed from porous fabrics that allow sound to transmit freely through the material.

This makes it sound as though the mat will have no effect on reflections. Am I misunderstanding something?

 

[keep_hope_alive Premium Member]

the stuff i used was actually salvaged from some pillowtop cushions i had - so the actual makeup/source is not known. it was a fairly dense sheet that was sewed on the ends.

in the future, pvc encased fiberglass will be what i use.

i wouldn't say it provides "sound damping" but sound absorption. water causes "dampening" - common misuse of the term. absorption comes from causing air molecules to generate friction or rapid increase/decrease in speed as it works through smaller openings. energy is lost in the process. even polyfill provides some absorption, though much less than fiberglass.

 

[keep_hope_alive Premium Member]

also, while we're on the subject of reflection dampening, ive been looking at purchasing a dash mat because the design of my dash panel is such that its pretty obstructive and likely causing alot of reflections. I was looking at buying a dash designs sedona suede mat, but on their website it says:

This makes it sound as though the mat will have no effect on reflections. Am I misunderstanding something?

open weave fabrics are mostly acoustically transparent - with some high frequency attenuation. you can RTA with and without the fabric covering to see for yourself.

so the answer to your question about absorbing reflections (the main reason we would want a dash mat) is: it depends on frequency. when a glancing reflection is caused (like apillar tweeters) the material seems thicker and some scattering at very high frequencies may be seen. but at 1k? nada. 4k? nada. maybe 10k and up.

maybe if the dash mat had a layer of SoundTex on top of an inch or so of open cell foam or compressed fiberglass...