A well thought out 15" Mayhem build...

[95Honda 486]

I am starting a build for a friend of mine. His goals are a decent amount of bass in a removable package. This will be installed in late model 4-runner.

After talking with Brian (BKOLFO4) about some different single driver solutions that would have good output he suggested a single Mayhem 15, and well, kind of going to take his word for it.

As for power, I bought a single Cresendo 3500, should be plenty of power. The 4-runner has a decent factory stereo (Nav and all that crap) so we wanted to keep what we could. I picked up one of the new Audio Control LC2i: http://www.audiocont...ol----LC2i.html because I am sick of PAC Trunk LOCs. They are POS's that are nothing but a headache. I only say this because I have installed about 10 of them. The LC2i also has a cool ciruit that defeats the factory compression of bass at higher levels... And remote turn on triggered by signal sense... Way cool.

He also bought a 250 amp alt and plenty of 1/0 and a stout battery. So good there...

Now, as for the box. This presents a few problems. It has to be small enough to fit behind the rear seat and we want to keep it below the window line. Brian suggested around 4ft3, I am going to go with that. A 30Hz tuning should work pretty good. Woofer and vent will fire back. 1.5" MDF construction, heavily braced. Inside will be heavily coated with Cascade Quiet Coat (I have 5 gallons left over) and outside will be proffesionally Line-X'd. Grill be solid PA style, steel with perforated holes and powder coated black. Will cover the entire back of the enclosure, flush with the cabinet.

Now, if there is one thing I hate, it is mounted electronics to the enclosure. But with this install, everything needed to be removable. So the amp and LC2i will be mounted to the front of the enclosure (against the back seat) with these isolation devices: http://www.zorotools...e_Shopping_Feed I am going to countersink them into the cabinet about 3/8" of an inch, so they won't be very visible. I did a little research, these should help alot in the range of vibrations the enclosure will try and transfer to the amp. Since the amp is mounted verticle, I made sure the shear rating was adequate, didn't want them sagging over time. I'll use 6 on the amp and 4 on the LC2i. They will be attached to the cabinet with T-nuts from the inside via studs with LocTite.

As for making everything removable quick via electrical connection, I am going with a single 5 pin Neutrik XLR: http://www.parts-exp...tnumber=092-328 for signal and 1/0 breakaways for power: http://www.parts-exp...tnumber=263-112 Nice thing is, for signal, I will use some 18/4 architechual cable with a nice braided jacket placed over it. It will look good and be simple and clean. There will only be the single break-away power connector and the single signal connector going to the box. 2 connections and your done...

Anyway, just waiting on the Mayhem right now, I'll probably start the box in a week or so. I'll post pics as the build progresses.

-Mike

[Aaron Clinton 2,372]

This should be good.

[///M5 2,833]

Awesome, love those 1/0 breakaway's and hadn't seen them before. I've always buried the electronics and only made the box removable, but love it.

[95Honda 486]

I am pretty sure they are the same design that has been used in places like charging stations for forklifts for decades... So should be OK for this application.

[nem 2,019]

Looking foward to this build and the ideas I may get from it.

[///M5 2,833]

I am pretty sure they are the same design that has been used in places like charging stations for forklifts for decades... So should be OK for this application.

I should have stated that differently, I've never seen them for sale nor realized they took 1/0. Definitely seen some high power plugs before....just never thought to search. I completely love the idea.

[edouble101 314]

What is the goals and plans for the front stage?

[95Honda 486]

It is the factory stereo. My buddy is pretty happy with it. Maybe he will chime in here and give some input...

[Adrian_D 520]

I am pretty sure they are the same design that has been used in places like charging stations for forklifts for decades... So should be OK for this application.

I've found them labeled as Anderson plus or connectors.

[topgun 262]

I am pretty sure they are the same design that has been used in places like charging stations for forklifts for decades... So should be OK for this application.

I've found them labeled as Anderson plus or connectors.

Those are on our forklift, and I've seen folks use them for connects on 12v truck winches.

[Kanaworm$ 292]

Tuned in for this build!

[Adrian_D 520]

I am pretty sure they are the same design that has been used in places like charging stations for forklifts for decades... So should be OK for this application.

I've found them labeled as Anderson plus or connectors.

Those are on our forklift, and I've seen folks use them for connects on 12v truck winches.

It's good stuff nonetheless. Definitely my choice for a removable amp or battery.

[95Honda 486]

I am excited to see how they work out in this particular install. I think between them and the XLR connector, it will really work good.

[StreetLegal 119]

I am pretty sure they are the same design that has been used in places like charging stations for forklifts for decades... So should be OK for this application.

I've found them labeled as Anderson plus or connectors.

Those are on our forklift, and I've seen folks use them for connects on 12v truck winches.

They are very efficent and used on various high amprage dc quick disconnect application, I have recently install one on a big ass hyster electrical fork lift, they are disconnected and connected at least twice a day and the one I replaced lasted approximately 6 years taking an abuse.

Edited June 12, 2012 by StreetLegal

[kirill007 52]

"Inside will be heavily coated with Cascade Quiet Coat".

Why do you coat the inside with liquid deadener?

I find the title funny

Good luck with the build, be sure to post some pictures.

[95Honda 486]

The combination of Line-X on the outside and liquid deadener on the inside provides outstanding deadening (opposite of constrained layers, but still effective) of the enclosure. It is especially helpfull when your bracing stiffens the box up signifigantly but raises the resonance points to high enough levels (frequency) that the dampening compounds can have a noticable effect. You'd also be surprised at how well an 1/8" coating of Line-X dampens the enclosure. Combine this with laminated cabinet walls and your golden...

When boxes are built right with these techniques, it is more effective than simply just going with thicker cabinet walls. And is better for weight/volume optimization.

[doc 0]

What is the goals and plans for the front stage?

Hey guys, I'm the person Mike is building this for.

The standard system in this rig is 90% perfect for me to be honest, it even has pretty good bass response (factory sub). It stays clean and gets loud, and I'm saying that as someone who has pretty high standards for audio systems.

Here's a link to what they put in there: http://www.jbl.com/toyota/4runner

Factory audio has sure come a long way; maybe in the future they'll start doing 3500 watt amps and 15s in 4 cu ft boxes?

[edouble101 314]

The factory JBL setup does look nice.

Doc, stop back in here when it is all done and let us know how it sounds.

[altoncustomtech 773]

Looking forward to seeing this done as well. Am curious on the Neutrik connector choice tho, just out of idle curiosity why you used the XLR instead of the Speak-ON?

Either way it's much better than most any other option and should work great for it. I'm tuned in for this one!

EDIT: NVM, I was thinking in my head that XLR was being used for the signal from the amp to the sub. Reading > ME.....

[95Honda 486]

Good question.

3 reasons for the 5 pin XLR:

#1, size. I am using 18/4 stranded cable that is roughly 1/4" in diameter. This fits perfectly into the Nuetrik chuck system with the braid over the top. You have to remember that the input impedance of an LOC is very, very high. So there will be no real current draw at all. 18 awg cable is completely overkill, 20-22 awg would be fine. The 5th pin on the XLR will be connected to the shield. I do not plan on connecting this at all, but may bond it to the source or load end, depending on wether or not I get any RFI/EMI interferance (very, very unlikely in this situation).

#2, complexity. The Speakons do not come in a male and female cable mount version. You need a coupler wich adds about 3" to the whole thing. And a part to loose...

#3, Speakon is overkill. They are rated at 20 amps. They are big and bulky (compared to an XLR). I am goint to be running in the neighborhood of miliamps... XLR is completely adequate, if not overkill also. I chose the XLR for it's ruggedness instead of something like a S-Video or DIN plug. I will put the female end on the cable interfacing the factory system so there is no chance of short circuit when the box is out and the cable is laying around.

Hopes this makes sense...

**Edit... Ha, just saw your edit, oh well I'll, leave the explanation up anyway...**

[95Honda 486]

OK, so the first batch of dampeners show up last week. They were much smaller than I anticipated. They are perfect for the LC2i, but too small for the amp. I order another batch in larger size. When everything gets here in the next few days I'll shoot some pics and show how I am going to orient everything...

[95Honda 486]

[95Honda 486]

OK, so the Mayhem arrived today. This things is pretty stout to say the least.

The 3500 and LC2i are oriented exactly the way they will be on the front of the box. You can see how tight the RCA connection will be. I am trying to figure out what RCA ends to use, I need to find some short ones. I was going to use some locking RCA's from Parts Express, but I think they will be too long. I see the P3 ones are pretty short... Any ideas? I plan on using microphone cable, I have several different types, 6-6.3mm O.D.

You can see the XLR connectors. I was making sure the cable will fit with the mesh braid over, I cut a small test piece. It fit fine and I could close the chuck on the strain relief all the way down. The cable is 18 awg 4 conductor shielded.

I am going to start on the box when I get back from New Mexico next week...

[Sencheezy 689]

Great pic!

[95Honda 486]

Thanks.

I am on the road right now, but I am trying to maximize the cabinet the cabinet dimensions. I ordered these grills and am going to use one for the front baffle:

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=262-884

The grill will sit flush with the front of the baffle. This poses a few problems. The first being that the grill only has 1" of standoff, and while this will be good for stability, it isn't enough to clear the woofer at full stroke. I need to set it at 1 3/4"" to be safe. So I will build a small (1/4") wide lip under it that is 3/4" tall. I will also have to build standoffs that are 1 3/4" tall, I plan on using 3/8" alumunim tubing cut to 1 3/4" in length. A 1/4-20 allen head capscrew will go from the outside of the grill, through the spacers and into the baffle with a rear mounted T-nut...

I also need to figure out what size to build the dimensions of the box so the grill fits inside with little clearance, taking into account the Line-X thickness. So I have a tad of work ahead...

Jesus Christ that Mayhem is a beast....