DIY sub for Klipschorn based HT (and music) - Tuba HT - build done (except for finish)!

[nyt]

Yeah, I rushed the finish on these like crazy. That side isn't visible so I didn't really care. The filler contracted more than I thought it would on the side there. I gave some spots a second coat but didnt bother with the other side. I just wanted my subs inside The visible sides look great though =] The flash also brings out all the imperfections like 10x what you see in person.

Are those brad nails showing on the outer edges?

(okay for the hammer and nails!)

[psg]

Most hardware stores will have some kind of material for gasket making.

Tape backed insulation will work, cork, construction paper, you get the idea.

Right. I submitted the order.

Glad you found something local. Shipping cost is outrageous sometimes, even here in the good old US of A.

Shipping across the border is always too expensive. The driver was US$159.90 at PE and C$177.85 (US$173.46) at Solen, so that's not too bad at all, and I avoid custom brokerage fees and the like.

[superedge88]

On my THT I ran the speaker terminals to the bottom, not on the access panel, personal preferance. It did take some forethought when running wires from the woofer chamber down through the horn path to the bottom but it was worth it.

[psg]

The visible sides look great though =] The flash also brings out all the imperfections like 10x what you see in person.

No kidding! It's almost impossible to make anything look perfect under flash photography. I'm sure it looks great in person and I can forsee the day when I ask about how to finish it. Might be cool to have the visible side veneered in Walnut Oil just like my Klipschorns! [^o)]

[superedge88]

This amplifier is the one that I was origninally going with, but was backordered when I tried to order it. Very cost effective, very impressive feature set ( take a gander at the user manual) and tested well on the AVS forum sub amp thread.

http://oaudio.com/500W_SUBAMP.html

So this is the one I ended up going with, I liked the feature sets that the Oaudio amplifier had, and this one had a very similar feature set.

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=300-811

The dayton tested out to have roughly the same output as the Oaudio amplifier on the AVS sub amplifier testing thread. I ended up paying about $100 for the Dayton, but I did like the fact that the Dayton could sit on my audio rack while the Oaudio one would have to either be mounted on the THT or I would have to make a box for the Oaudio to mount on to to sit on the audio rack.

[psg]

Good idea about the bottom mount since that hides the connection from every side! (Needs a bit of lifting to plug it in though.)

I haven't decided anything about an amp yet. I have a power amp with meters and I'll see how much power the sub draws. I have an old HK avr-325 receiver that I could use a 65W channel out of. Or I'll buy a Behringer EP2000 for C$300 and get 1300 W bridged into 4 ohms! I do like the EQ features of the first one you showed.

[superedge88]

I do like the EQ features of the first one you showed.

Which is exactly why it was my first choice, a ton of headroom for the THT, EQ features that you don't find on every amplifier, a price that is undeniably awesome, and proven through extensive testing on AVS forum

http://www.avsforum.com/avs-vb/showthread.php?p=11318800#post11318800

(scroll up to post 232 to see the unboxing)

Also something of note: Looking at the measured specs, it shows it supplying up to 44 volts, the THT with the dayton woofer in most home theaters will never even demand more than 30 volts during the most bass heavy movies.

[CECAA850]

Also something of note: Looking at the measured specs, it shows it supplying up to 44 volts, the THT with the dayton woofer in most home theaters will never even demand more than 30 volts during the most bass heavy movies.

I've been doing some reading at the BF website and people are always referring to limiting and or checking voltage in reference to protecting the drivers. I don't see how it's checked. Do you just parallel a volt meter to the speaker wire? AC or DC?

[nyt]

Also something of note: Looking at the measured specs, it shows it supplying up to 44 volts, the THT with the dayton woofer in most home theaters will never even demand more than 30 volts during the most bass heavy movies.

I've been doing some reading at the BF website and people are always referring to limiting and or checking voltage in reference to protecting the drivers. I don't see how it's checked. Do you just parallel a volt meter to the speaker wire? AC or DC?

Most people don't even bother. easy way is to just put a volt meter on the terminals and see what it's doing.

I have two of them, with both receiving ~15v max, 5m from each, I was hitting 125db.

figure one of them would be hitting about 120db at the same location, from 15v at 5 meters, in a completely open room to 1200sqft.

hitting xmax will only be a problem around 22hz due to the horn, and I believe the limit was around 28v.

It's not something you need to be terribly worried about. I've beaten the piss out of these things and they just shrug it off.

[CECAA850]

I'm going to build one of the Tuba 18's and won't be pushing it very hard in 2 ch., I was just curious. I've got an IB in my HT that I'm very pleased with. Do you set your meter on DC?

[nyt]

I'm going to build one of the Tuba 18's and won't be pushing it very hard in 2 ch., I was just curious. I've got an IB in my HT that I'm very pleased with. Do you set your meter on DC?

Nope. It's AC.

[CECAA850]

Thanks.

[psg]

First class this evening... but no cutting just yet. That starts next week.

Got my order into Solen last night. The Visa checkout site didn't charge me for shipping, so we'll see if I even end up paying for it. C$217 so far, for the driver and misc hardware (like the terminal cap and T-nuts and bolts) and taxes of course.

[psg]

Does anyone have cut sheets for a 30-inch? I have to work out if it's better to get 4x8 or 5x5 for this build (it could even be a combination!).

How much glue do I need to buy?

I'd like to use cookies to hold the parts in place while the glue dries, instead of nails or screws. I'd likely sand the walls prior to assembly and might stain the baltic birch to match my walnut oil Klipsch speakers. So there would be no screws or nails showing on the outside. No problem with that? (I have actually yet to read through the whole plan; it's not light reading and hard for me to follow.)

[CECAA850]

I'm still hung up on not being able to use wood glue. I don't see why you can't use wood glue and then run a small bead of glue in the seams if you don't get a good push out of glue. To me there's nothing stronger. I've built several boxes with it and never had a leak. I have not however built a horn sub before.

When you say cookies, are you referring to buiscits? If so, you'll still need to clamp when gluing.

[nyt]

You're going to need three 4x8 to do 30" if you do it with no mistakes. I ended up cutting 8 sheets to build 2, but I have a few mistakes. stuff happens when the only time you have to build speakers starts after midnight . you will need a lot more 5x5 to build that since each 36" side is gonna leave you with a lot of unusable scrap. 2-3 of the standard caulk gun sized PL Premium should do the trick.

The reason PL is used is due to the way it dries and expands to seal cracks, instead of shrinkig. Its also polyurethane, it will not degrade as much over time.

Also, there are lots of long cuts on this, they will not line up exactly perfect, and due to the size there may be some warping as well. PL fills these gaps very easily.

Thats why wood glue isn't used here.

And a bit of advice about PL, don't smooth it out with your finger on the outer edges where it squeezes out. You can let those dry then just peel them off by hand or with a razor really easy. Insie its fine to smooth it, just don't do it anywhere you want to paint or finish. Also, get some nitrile or latex gloves for working with it. It gets everywhere and doesn't wash off hands so easy.

Using a biscuit joiner will prove troublesome for you once you get to laying down the inner pieces. If you do use a biscuit joiner, your build will be slower, since you will have to wait for the glue to fully dry and hold the pieces in place before you can move on.

Does anyone have cut sheets for a 30-inch? I have to work out if it's better to get 4x8 or 5x5 for this build (it could even be a combination!).

How much glue do I need to buy?

I'd like to use cookies to hold the parts in place while the glue dries, instead of nails or screws. I'd likely sand the walls prior to assembly and might stain the baltic birch to match my walnut oil Klipsch speakers. So there would be no screws or nails showing on the outside. No problem with that? (I have actually yet to read through the whole plan; it's not light reading and hard for me to follow.)

[jason str]

Follow the plans and you will have no problems.

Use nails, the glue (P.L. premium) holds the project together. Biscuits are unneeded.

Once the project is together there is no way to fix your mistakes besides cutting the sub open, P.L. expands and will have your back.

You may get more help with cut sheets using Bill's forum, i have not seen any personally besides whats in the plans.

I did not use any clamps, just scrap pieces of wood & nails like everything else i built in the past 30 years.

[psg]

Thanks again evryone for all the responses.

Yeah, I meant biscuits (they look like cookies to me). I was under the impression that you had to wait for each part to dry before you moved on anyway, so using biscuits wasn't going to slow me down, but allow me to push the piece into the glue without fear of it moving from its spot. Time to actually read the plans I guess!

My fear of nails is that I would prefer all outer surfaces to be free of nails and screws (except for the access door) so I can stain the whole cube to match my speakers and let the wood grain show. Someone even suggested cherry pegs! The different color would show off the horn folds from the side of the box.

[jason str]

Countersink the nails & use wood filler to match your wood tone/color.

The other way out is veneer or thin plywood.

[nyt]

filler will show up a different color most of the time when stained.