Dixie's TriTrix mod

[JoshuaC2U5H]

Hi there,

This is my first speaker build though I'm not foreign to fabration or general mechanics and woodworking. I plan on keeping it easy on myself and build the sealed TriTrix design from the Parts Express kit, but I want to add a side-firing 8" or 10" ported subwoofer with the port in the front or rear. Hopefully I can get good extension with this type of setup, though I'm kind of at the mercy of the knowledge base here. I've build subwoofer boxes for cars in the past so I know how to do sealed enclosures built to a specific internal volume with bracing and tuning, but I'm no wizard!

I'm building these as a Christmas gift for my girlfriend, and they'll be 95% used for music. I'd like to build them as a tower and use the lower portion for the subwoofer, firing to the side. I chose the sealed TriTrix MTM so I can keep the cabs smaller, though because the design only calls for a 6-¾" deep enclosure it doesn't give me much room for a subwoofer.

1. Does this sound possible at all?

2. I know I'll have to adjust the depth so I can get the subwoofer in there. I'd like to use the Dayton RSS210HF-4 8" subwoofer, but I'm obviously completely open to sugestions here, especially if I can get better or equal results for less. I understand it's a 280W RMS sub which might overpower the rest of the setup, so maybe the Dayton DCS205-4 would be a better match at 150W RMS, but again: what do I know. I'm planning on building the sealed 0.8 Qtc sized MTM enclosure for the top portion, with an internal back wall for the MTM portion so I can get the depth for the subwoofer extending behind that.

3. If one of these subwoofers would be enough, and to reduce cost, I'll build the other tower to match without the sub in it. Needs ~1.75 ft³ for the bottom subwoofer portion. Have no idea what diameter/length port to use.

4. Dayton SA100 for the subwoofer plate amp? Wire the sub for 4Ω to get 100W RMS out of the amp ... underpowering it? Maybe I could get better value running a rack amp to power the subwoofer, but I don't know how that would fair with the ease of use for her and I don't think she'd like an "extra box," other than the receiver to run the MTMs, hanging around.

I appreciate al input, Thanks!

~JC

[johngalt47]

The first answer is no for two reasons. One, not enough volume for the sub, and two, the TL design would be messed up.

I do like the RSS210 but in a sealed cab it requires .5 cu ft all by itself as a minimum.

[JoshuaC2U5H]

The first answer is no for two reasons. One, not enough volume for the sub, and two, the TL design would be messed up.

I do like the RSS210 but in a sealed cab it requires .5 cu ft all by itself as a minimum.

I'm basically talking about building the sealed bookshelf design, but make them a tower with the lower portion the subwoofer enclosure, not using the TL config at all, since I won't need the bass advantage the TL design has over the sealed with the sub.

[technodanvan]

The first answer is no for two reasons. One, not enough volume for the sub, and two, the TL design would be messed up.

I think the intent was to make the sealed variant of the TriTrix, which would leave 'some' volume below.

One concern I would have is the depth of the subwoofer driver. I don't think the TriTrix is particularly wide so you'd have to pick a sub with a fairly shallow motor. Probably not one of the long-throw designs.

I'm also not sure a sub that fits within the constraints is going to give all that much more depth than the TL version of the design in the first place. There have been some successful small subs using 6"-8" woofers that might fit in there...

[JoshuaC2U5H]

I think the intent was to make the sealed variant of the TriTrix, which would leave 'some' volume below.

One concern I would have is the depth of the subwoofer driver. I don't think the TriTrix is particularly wide so you'd have to pick a sub with a fairly shallow motor. Probably not one of the long-throw designs.

I'm also not sure a sub that fits within the constraints is going to give all that much more depth than the TL version of the design in the first place. There have been some successful small subs using 6"-8" woofers that might fit in there...

Gotcha, maybe I was just thinking about this unrealistically—but that's why I posted! Maybe I'll build a small separate subwoofer as a gift later on if she starts using them more for HT purposes. From the reviews, it sounds like the TL deisgn of the TriTrix will provide adequate musical bass down into the low 40 Hz range.

Thanks for the wake up call!

[technodanvan]

I haven't heard the TriTrix but I'll bet the bass out of it will be pretty satisfying on its own.