Autotuba/Floorstanding speaker worklog with pics.

[mastertee31]

mastertee31, I will assume that you live in a fairly populated area. Are there kitchen cabinet makers in your area? I'll bet there is. Stop in one day and ask them where they get the high grade plywood that they use. You might even be able to work out buying from them, saving you run around time and money. Plywood is used for a couple of reasons. It's cheap, it's very strong when used as directed, it's much lighter in weight, it's easier to work with, it doesn't soak up moisture like a sponge...the list goes on.

If you will post where you live, I am sure someone on the forum will guide you to a source for good plywood.

BTW, if you are in the US, seriously consider building a set of SLAs. With your skills, I think you could knock a pair out in a day, sans finish. They are inexpensive to build, sound fantastic, and are a pretty easy build. I am finishing my first one, that I have built one-handed!

Unfortunatly I live in Montreal (There's a ton of snow here lol). Plywood is starting to seem like the better idea now that most of the speakers are coming together. (They'll break your back if you try to lift alone!) I wanted weight, but not this much!

[DJPhatman]

That is not unfortunate, as Baltic Birch plywood is available there. Sheets are ~ 2 meters by 2 meters, 12 or 13 mm thick. or, 10 mm if you can get it. There are others from Quebec on here that can send you the proper places to get the good plywood.

[Bill Fitzmaurice]

There's no shortage of BB in Quebec. All of the Russian and Finnish BB for the eastern North American market comes through the ports of Montreal and QC.

[mastertee31]

Hmmm, I live on the west side of montreal with about 4 hardware stores nearby. Everytime I ask about BB they give me a confused look lol. I guess I'll have to ask a cabinet maker for future projects, where they get their materials.

I do have a question though, I have one cab almost completed at the moment (Without the speakers on top). It's wired to a plate amplifier I have from another sub (This is not the amp I have plans to use, I will order the recommended one from parts express) Anyhow the amp I'm using is rated to pump out 70wrms, It's crossed over at a low 70Hz and the gain knob at half. After a couple of songs to evaluate the bass, I'm not too impressed. I played around with placement and to no avail, sure it's noticeably louder when firing into the corner of a room but it sounds quite muddy nonetheless. It's also not nearly as clear as described... I guess my question is: Can all this boominess/distortion/muddyness be attributed to not having enough power? I imagine the extra power will help to control the suspension a little better? Is my logic flawed in thinking that the autotuba would be exceptionally good for home stereo music?


And before anybody asks, yes I checked for leaks. None.

Thanks

[Gauss]

At 70hz and under, there should be no directional difference, so pointing them into the room is pointing to a problem of higher frequencies. Is this the modified Autotuba? From the charts, and what others have posted, it looks like it needs a crossover to bring down everything above subwoofer territory. I'd suggest testing it with an EQ, and also being aware of the room's resonant frequencies.

[Bill Fitzmaurice]

It's also not nearly as clear as described... I guess my question is: Can all this boominess/distortion/muddyness be attributed to not having enough power? I imagine the extra power will help to control the suspension a little better? Is my logic flawed in thinking that the autotuba would be exceptionally good for home stereo music?


And before anybody asks, yes I checked for leaks. None.

Thanks

The output of a subwoofer alone is nothing but mud. All definition and pitch information is in the midbass and midrange. A really good sub never makes its presence known, until you turn it off and notice how thin everything sounds without it. Boom comes from the midbass as well, not the sub bass, so I'd say your crossover has insufficient slope. Compensate for that by lowering the LP frequency.

[mastertee31]

As promised Updates! Compromises have been made in design, but I've pretty much completed speaker #1, It just needs some cosmetic work (Filler and a good pass with the router) Unfortunately paint will have to wait until summer when it's warm and I can do it outside. I'm still undecided on what type legs/spikes I will use...















That's it for now...

[Rickisan]

mastertee31 - Accolades to you on the project pics. Shows great attention to detail. Good to see the updates. Keep 'em coning and thanks for sharing!
rickisan
ps oh yeah... nice foliage... lol

[Mikey]

If you haven't cut the baffle yet, it's not too late to convert that top to an SLA (using the existing cab, with minor modification). It will sound a LOT better than what you have planned.

[djohnson573]

oh yeah... nice foliage... lol

I was thinking the same thing.

[mastertee31]

oh yeah... nice foliage... lol

I was thinking the same thing.

LOL! I didn't know what you guys were talking about until I took a better look at my pics. Those are my dad's plants he brings in during the winter to keep them from dying. There not what you think...

[mastertee31]

Updates!!! I skipped a few lol.

Holes cutout, routered edges, and filler... lots and lots of filler:


Some High build primer 1st coat:


Primer/Sealer done on top cabs:


First coat of gloss black verathane enamel, should be good with 2 more coats...:


Couple of spots where my gun spit a little, but should be alright with sanding in between:


More updates later in the week.

[mastertee31]

O.k.,O.k. I'm lazy with updates but I am closer to completion! I can finally see the light at the end of the tunnel... might be a train lol. Since my last post I've managed to get down 3 coats of Varathane Super gloss lacquer, with 80+ hours of sanding thereafter (400,800,1200,1500,2000 grit wet sand). Honestly when I read up on how much work piano black finish was I shrugged it off, If I had to do this again I might reconsider. It's not 100% up to my standards but I'll have to settle. Here is 1 speaker complete minus the sub amp, spikes, and speakers mounted (The side covers for the access hatch will be a project for another day) These have been buffed with Meguiar's diamond cut compound on a wool pad, and then Meguiar's polish/glaze compound on a foam pad. All this is topped off with a layer of Meguiar's gold class carnuba wax, and a hand rub out. Final assembly and listening tests of the top cabs should be good for the weekend...

Nice deep gloss:




A close up so you can see that there is 0 orange peel!:



If you guys can pick out any defects, it's either the camera or dust. Pics do not do these justice.

[Dave Non-Zero]

wow.

[LelandCrooks]

ShamWow