Audio Build Log: The Gnome's 2017 Silverado

[ProjectTwin]

Sub enclosure progress.

87 pieces to this thing.

Some of the port stacks are dry fit right now while I wait for the wood glue to cure before sanding.

Have some excess glue to remove where I joined the enclosure walls to the floor before I put the stacks in their final location.

 

[gunracer1]

jesus, impressive

 

[anatram]

Holy shit if your work was any sexier it would have pasties and half my paycheck.

I am building a multi part box for a 12" sub-woofer for a jeep JK right now. It wedges between the rear seat and the roll bar just above the wheel well. It's doesn't hold a candle to stuff you build.

 

[TRINDU]

Is the port that long so its tuned to a certain Hz?

I always thought you wanted it exiting to open air, for the lack of a better term, and not exiting against something such as the door panel.

not questioning your work, I genuinely want to understand what you're doing

 

[Firstram]

Is your CNC too small to cut out the parts in slices? It seems like less work to laminate layers up just past the port and add the angle or bandsaw the front after layup.

 

[bdkw1]

Is your CNC too small to cut out the parts in slices? It seems like less work to laminate layers up just past the port and add the angle or bandsaw the front after layup.

And waste a shit load of material? The corners are easy to nest and you don't loose much material.

 

[Mattafact]

If I were to guess I would say he did it that way to have gentle curves and reduce distortion from the port.

 

[ProjectTwin]

Is the port that long so its tuned to a certain Hz?

I always thought you wanted it exiting to open air, for the lack of a better term, and not exiting against something such as the door panel.

not questioning your work, I genuinely want to understand what you're doing

Yeah, tuned to 30Hz. Port is 5"x4" and needed to be 48" long to tune the enclosure to 30. More enclosure volume with same port area would mean a shorter length port.

I initially wanted to tune to 25Hz but didn't have the space to get both port and airspace for the subs.

As it is I'm at about 1.25ft^3 for these two 8s.

And this will load off the passenger rear door panel. Did this in the F150 with a pair of these 8s. Broke the bond at the B-pillar roof support on 1,100W.

We'll be sending 3,800W to this pair.

 

[ProjectTwin]

Is your CNC too small to cut out the parts in slices? It seems like less work to laminate layers up just past the port and add the angle or bandsaw the front after layup.

Stack fab is cool when used properly. As simple as clicking "run program" I can get radii and such that would be time-intensive to do on the router table.

A lot of guys a few years back would do stack fab when it was unnecessary just to show that they were doing it. Cracked me up.

If I don't need to stack pieces I'll used sheet whenever I can. Just makes sense. The stacked port pieces were cut from 20" x 10" or smaller scrap. The small pieces in the 2nd turn of the port (from the exit at the enclosure) have a stack that takes the 2 1/2" internal wall radius and converts it to a 4" inner radius so the port stays a consistent width throughout the bend. Cut those from some 6" square scrap.

Getting ready to cut the lid for the port. Just drew it up and need to get the CNC going.

 

[TRINDU]

And this will load off the passenger rear door panel. Did this in the F150 with a pair of these 8s. Broke the bond at the B-pillar roof support on 1,100W.

We'll be sending 3,800W to this pair.

is it better to "load" the port off structure? Or send it to a void in the cab?

3800 @ 1ohm?

 

[Pt_Ranger_v8]

Right at the exit port, will that lack of curve affect anything?

Not that I think you'll hear it at 3800 watts

 

[ProjectTwin]

Right at the exit port, will that lack of curve affect anything?

Not that I think you'll hear it at 3800 watts

That exit is different from that photo. If you follow the radius that feeds to the mouth of the port, the small shoulder in front of it is now gone. That was always the plan. I have more pics. Will upload later.

 

[ProjectTwin]

is it better to "load" the port off structure? Or send it to a void in the cab?

3800 @ 1ohm?

Options are kinda of limited when packing two subs and this much port under the seat.

I’ve always fired the port to the corner opposite the driver and they‘ve loved it.

I debated firing this port to the rear, but didn’t like how it looked at the exit and internally.

So...back to the side-firing set-up.

 

[Arps]

wow! that is stupid impressive

 

[HillbillyDeluxe]

When I finally get over the hurdle of getting my own semi, you're doing the audio install on it. Imagine what you can do in a 72" sleeper thats 102" wide and has 4 batteries stock with more than enough room on the frame for 4 more ​​​​​​

 

[ProjectTwin]

Right at the exit port, will that lack of curve affect anything?

Not that I think you'll hear it at 3800 watts

Take a look at the port exit. The height of the port is 5 inches. The short block with the roundover on it is the right wall of the port exit (left in this photo). If you go 4 inches to the right in the photo you'll be at the inner back wall of the enclosure. I routed an opening in the end of the enclosure that travels along the short block, across the bottom, up along the back wall (removing that non-radiused 90 degree section on the right), and then across to the left (in this photo) port wall.

Here's that opening routed in the enclosure. If you look at the top left of the opening you can see the remains of that little stepped 90 degree bit you were asking about.

This image should should clear it up.

With the port opening cut, I needed to get rid of that hard 90 at the mouth. That meant it had to go to the router table.

A little filler was used to smooth the transition at the port mouth so it's smoother. That elliptical radius bit really opens up the mouth of the port and reduces turbulence.

 

[Arps]

 

[ProjectTwin]

Off to Line-X

 

[ArTi54N]

so schweeet

 

[gunracer1]

pop me one out in your spare time. nice.

 

[2big bronco]

Ball park what does a custom box like that run with all the figuring and stuff?

 

[ProjectTwin]

Ball park what does a custom box like that run with all the figuring and stuff?

$1,500

 

[Toreadorranger]

$1,500

That is a smaller number then I was expecting.

 

[ProjectTwin]

That is a smaller number then I was expecting.

*kicks dirt

Enclosure is back from Line-X.

Made a 3.730" template on the CNC so I could cut a step in the back of the enclosure.

I then put the CNC to work again making a template with a 3.73" OD and a 2.75" ID.

I stuck that template into the pocket I had cut in the first picture.

...and routed a through hole.

Now I have a .400" step with a through hole.

This allowed me to flush mount the SMD terminal cup.

View attachment 118695214_183698759800576_3173985980058628622_o.jpg?_nc_cat=105&_nc...xx&oh=3210e657dfb804adf3351127

Getting ready to wire and load the subs. They're DD Audio 2508 ESPs.

DD includes wire nuts with their subs that have direct leads. I use them but wrap them with Tesa tape so they don't try to come loose.

Spax screws were used to mount the subs.

Ready to go in the truck.

 

[Arps]

That is fucking sick! My Silverado needs one.

 

[ProjectTwin]

Almost done.

Making final connections now.

Used a GM-650-M from Nav-TV to integrate into the factory radio.

Ran remote wire for both amps and added subwoofer cabling.

The Gnome is wiring the subs.

Set the gain structure and crossover points and had to do some initial listening. I don't have the tweeter pods ready to go in yet so we just ran the DD 6 1/2s and 3-inchers. I didn't low-pass the 3-inchers. Instead I let them play all the way to 20K to give him better sound until the tweeter pods are done.

When I get the tweeter pods done and installed I'll do an actual tune on the thing.

Initial listening was fun. Crazy loud inside, but thanks to all the sound deadening there's no interior panel vibration, no door skin flex, or other annoying stuff.

There's very little vibration at all. We have a little at the rear-view mirror and the overhead console.

Right now the seat is going back in while I do more sanding/smoothing of the pods.

 

[bigun]

 

[Alpine4x4]

Why not just nix the wire nuts and solder the connection or use a butt connector? I personally hate wire nuts haha.

Sick build, the box work is amazing.

 

[ProjectTwin]

Why not just nix the wire nuts and solder the connection or use a butt connector? I personally hate wire nuts haha.

Sick build, the box work is amazing.

Because I'm not going to fawk around with trying to solder/de-solder three 8 AWG cables at one connection. Four times.

The wire nuts work. I tape them. Never had an issue.

Working on the tweeter pods.

These are built from fiberglass filler. They're rock solid.

I'm attaching them to the A-pillar with 8-32 machine screws and EZ-Lok inserts.

I'm working up in size to allow them to thread in. Easier to step up in size with this fiberglass filler than to try to hog out the final diameter.

To get a perfect fit at the pillar I just apply a final bit of the fiberglass filler, put the pod in place, and let it squeeze out. After it cures I'll give it a final sanding then prime/texture/paint.

 

[budget76]

awesome work. it makes my best attempts at a clean wiring install look hack

Looking at your pod mounting - looks like the EZ-lock work for you and no reason to change, but curious if you ever looked at rivnuts for that use? may or may not be an easier or more secure installation, but i've never worked with the EZ-locks