Starting to build a Home Theater

[Halon451]

Looks like excellent workmanship on that sub box, Skyline - looks great? I'm assuming this isn't your first time making one - seem to know what you're doing. That enclosure is HUGE!! I'm just curious as to how it sounds!

 

[skyline_123]

Really really nice, man... Can she cook?

Haha, I was hoping someone was going to get that SNL reference.

...and YES!

Looks like excellent workmanship on that sub box, Skyline - looks great? I'm assuming this isn't your first time making one - seem to know what you're doing. That enclosure is HUGE!! I'm just curious as to how it sounds!

Thanks. This was my first time making one. You're right, the enclosure is huge. Below is a picture showing the size difference between the Dayton 120 and the Simple Build. The Dayton seems like a smurf in comparison. Next time I build one, I'll set it on casters for easy set up.

 

[Shock]

Your dogs head looks extremely soft, I want to touch it.

 

[skyline_123]

More Dane pics please.

As you wish:

http://forums.audioholics.com/forums/showthread.php?p=684655#post684655

Your dogs head looks extremely soft, I want to touch it.

Umm...I'm sure the feelings mutual.

How about the fan mod for the EP2400. Moderator mikec has a thread on it somewhere.

Done! Oh how this was soooo necessary. The only time you can hear this thing is when the A/C or heater in the house turns off and there's a silent point in a movie or music. It's wonderful. It's what I call a must-mod. Thanks MikeC.

 

[tn001d]

More pics of erin please

 

[skyline_123]

The wife unit has always forbid the presence of speakers in our master bedroom until I mentioned the very small Overnight Sensations. It was a good first DIY speaker building experience as well because of the low level of complexity and small cabinet.

I attacked this enclosure by building the main structure first and then wrapping the side. This proved to be very time consuming because you had to glue and clamp the individual layers one at a time while the glue set up. Also, and this was ultimately the downfall of the entire design, I cut my front baffle to size first and THEN built up the walls to meet that width. I should have built up the sides to however thick I wanted the walls to be and then flush trimmed the baffle to match. Stupid mistake. I’m glad I did make that mistake because I like the second attempt much better because it gives you much more flexibility as far as the shape of the enclosure, the thickness of the walls, and the integrated bracing.

For the shape of the enclosure, I hand sanded a template for the top and bottom pieces and then transferred that shape using a flush trim bit to 4 pieces of MDF. This was really nice because you're completely unrestricted as far as the shape goes. Once you feel like you got the right curves, you simply stop sanding and transfer that shape to as many pieces as you want.

Here’s the failed first attempt:

 

[skyline_123]

You can see here that the two sides were done a bit differently. The first side was bent without any stress reliefs and was considerable more difficult to bend. I even tried steaming the wood but that didn't work. It's basically a 3/16 inch mahogany veneer and doesn't take to water very well. Oh well. The second side was done with 3/4 MDF. This was pretty nice but except that it left you with a very hollow sounding side. I remedied this with 4 layers of peel and seal and filling the voids with sand.

 

[skyline_123]

Well, I have to switch picture attaching methods, these embedded attachments aren't working out too well for me.

For the MDF side, I had to apply the peel and seal before attaching it to the enclosure because I didn't want to attach the side and then have to apply it by having to stick my hand through the hole. I did this by clamping a dummy template to give the MDF the right curvature and then apply the peel and seal.

 

[skyline_123]

Here's the second attempt.

 

[skyline_123]

More pictures

 

[skyline_123]

More pictures

And this is how they sit right now. I've been listening to them in my living room, which is open to the kitchen, and despite the large space to fill, they sound really nice. They don't get very loud to where you're having to scream at the person next to you to talk but you do have to raise your voice to a near yell. I now have them in the bedroom which is considerably smaller and they sound THAT much better. They definitely go much lower in the bass compared to when they were in the living room. Just like everyone else has described them, these little guys have a BIG sound and are surprisingly accurate. When comparing them with other speakers, they sound a tad bid tin can-ish but it's never to the point where I think that when I'm simply listening to music and not comparing them. I really want to hide them behind a curtain and have people listen to them first and then show them what's been creating the sound just to see their faces. A buddy of mine came over and gave them a listen and the first song I played put a big smile on his face. They're really quite impressive for their size. I will post more pictures when I put a finish on them. I bought some walnut veneer and I think I'll experiment on the failed enclosure for veneering practice. Any thoughts or suggestions for veneering is greatly appreciated.

 

[Alex2507]

It's good to see that scroll saw got put to good use. That's pretty far from a simple enclosure and it looks like you did a fine job at it. How did you calculate the 4.5L volume with that odd shape? Is that engineering degree kicking in on the DIY speaker front?

Be careful terminating a port adjacent to a brace or even having it up against a side wall as that extends the port IIRC from some stuff I read at JL Audio. Annunaki linked it way back. Kind of a must read. Maybe he'll find this and link it again.

The veneering and finishing should prove to be a monster PITA. I don't envy you that. What's the source going to be for the bedroom? I take it the old rec'r is going to power these up?

BTW, seal that MDF before you do anything to it. I'm not sure why.

 

[jostenmeat]

Wow, those speakers look superb! So, let me get this straight, just four months ago you buy a table saw and router, and now you've already built the Kappa Perfect, these difficult cabinets, and crossover to boot. Dang, deez skillz must be in the genes. Or you have an extremely helpful uncle. Or both.

 

[skyline_123]

How did you calculate the 4.5L volume with that odd shape?

I took sort of a nerdy approach to calculate the volume. I took the template that I was going to use to transfer that shape to all the other pieces and I split the cross sectional area of that template into rectangles and arcs. I only analyzed half the template because the other half is identical. I then looked at the curved portion like the curve of a graph. I took a few measurements and I entered these values in an excel spreadsheet and had it pump out an equation for the line. You can then take the integral of that equation to give you the area under the curve. I took that number and multiplied it by two for the other side and added it to the simple rectangular shapes of the rest of the template to give the total area and multiplied it by the height. I also subtracted out the volume of the brace and was left with roughly 4.5 liters. I did take into consideration the thicknesses of the box.

The veneering and finishing should prove to be a monster PITA. I don't envy you that.

I'm going to try the vacuum bag method. I'll post some pictures when I get started on that one.

What's the source going to be for the bedroom? I take it the old rec'r is going to power these up?

Zone 2 on the main receiver.

BTW, seal that MDF before you do anything to it. I'm not sure why.

gmichael posted this link and if you read it, it goes on to say you need to watch out for cracking whenever all those layers start aclimating to the humidity levels in your house. I think one guy claims to wait at least a week before veneering.