Hello everyone! Ready to give me your input?

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DJPhatman · #46 Post by **DJPhatman** » Sat May 17, 2008 1:11 am

DO NOT USE MDF, MDO, or ANYTHING other than good quality plywood, with at least 5 equal plys. MDF and MDO are composite material that will not hold up to the the strains of load cycles, and they are heavy as hell. Follow the directions. Follow the directions. Follow the directions. Don't second guess the driver recommendation. Don't reinvent the wheel here. Bill has years, nay, decades of experience in these designs, and shares his experience with us for a pittance of cost! The only ones who are not happy with them are those who don't follow the instructions and use non-recommended drivers.[/rant]

The passive crossover is there for those who use the sub for back line or low power PA. If you are using an active x-over,which you should be using, then you don't need a passive x-over.

Yes, you can parallel these cabs together. In fact, it is recommended! Just be mindful of the impedance load.

EDIT: Also, REDLINE, I DJ with a pair of HL10C dual loaded T39s. They will bury any commercial sub that you could buy without spending a fortune. My pair have made EAW owners cry!

REDLINE · #47 Post by **REDLINE** » Sat May 17, 2008 5:52 am

DJPhatman wrote:DO NOT USE MDF, MDO, or ANYTHING other than good quality plywood, with at least 5 equal plys. MDF and MDO are composite material that will not hold up to the the strains of load cycles, and they are heavy as hell. Follow the directions. Follow the directions. Follow the directions. Don't second guess the driver recommendation. Don't reinvent the wheel here. Bill has years, nay, decades of experience in these designs, and shares his experience with us for a pittance of cost! The only ones who are not happy with them are those who don't follow the instructions and use non-recommended drivers.[/rant]

The passive crossover is there for those who use the sub for back line or low power PA. If you are using an active x-over,which you should be using, then you don't need a passive x-over.

Yes, you can parallel these cabs together. In fact, it is recommended! Just be mindful of the impedance load.

EDIT: Also, REDLINE, I DJ with a pair of HL10C dual loaded T39s. They will bury any commercial sub that you could buy without spending a fortune. My pair have made EAW owners cry!

No I wasn't trying to offend Bill at all, but my father told me all speakers are made of MDO board, so i'd figure it wouldn't hurt to ask. I also think i'm leaning towards the HL10C just because it's really powerful and I would be able to make these 14" which is really small.

If I plan on carpeting this Titan 39, I should everywhere except the mouth of the horn, correct? I really like a carpet look, plus it will match all my other stuff, i'm just not sure how far/close I can carpet to the mouth of the horn.

Tim A · #48 Post by **Tim A** » Sat May 17, 2008 6:08 am

REDLINE wrote: No I wasn't trying to offend Bill at all, but my father told me all speakers are made of MDO board, so i'd figure it wouldn't hurt to ask.

Beware the experienced woodworker! The materials go against everything he knows. Do not stray from them. Do not use anything but the recommended wood.

CRITICAL! Do not use any other type of adhesive. Use PL only.

REDLINE wrote:If I plan on carpeting this Titan 39, I should everywhere except the mouth of the horn, correct? I really like a carpet look, plus it will match all my other stuff, i'm just not sure how far/close I can carpet to the mouth of the horn.

You can carpet the mouth too, it won't have any adverse affect. The bass waves won't even know it's there.

AntonZ · #49 Post by **AntonZ** » Sat May 17, 2008 6:25 am

REDLINE wrote:Wow this is crazy stuff, I feel like my whole world has been flipped upside down.

Be prepared for some more double back flips every now and then. This forum is an audio rollercoaster. Sit back and enjoy the ride

Do not use MDO, MDF, HDF or particle board, use good quality ply. Birch ply is my favorite. I first heard about it here, it's a joy to work with. Don't get the ply with a very thin outer veneer layer - it will delaminate easily. Use ply with all equal layers and few or no voids. Spruce or poplar ply is lighter, dents easier and is a little more grainy on the surface but these are no issues if you use carpet. I think this is all in the plans, just read them again and again, it takes some time to get your head wrapped around everything that's in there.

You can carpet into the horn mouth of a Titan.

REDLINE · #50 Post by **REDLINE** » Sat May 17, 2008 6:50 am

Wow, I didn't realize I could carpet into the horn mouth, that's awesome. So basically I can carpet up it just far enough so you couldn't see any wood, and not need to paint/duratex anything?

Also, does anyone have any good links of how to carpet a cabinet?

Sydney · #51 Post by **Sydney** » Sat May 17, 2008 7:01 am

Do a search on this forum for "carpet" and you get a lot of threads:
Including this one.
http://billfitzmaurice.com/phpBB2/viewtopic.php?t=3791

IMHO: I 'd rather Duratex than use rat fur.

REDLINE · #52 Post by **REDLINE** » Sat May 17, 2008 7:37 am

Thanks sydney.

I've been trying to search for a chart of the T39 with dual S2010s, but it doesn't seem one exists. But I wanted to know, if you dual 10" drivers, the minimum width is 22", correct?

Ron K · #53 Post by **Ron K** » Sat May 17, 2008 7:52 am

As far as wood goes the 1/2" Arucco Ply is 5 equal plys void free. It's strong and light weight and if you're building the slimmer versions should be just fine. For the wider versions you might want to use 1/2" Baltic birch.

The MDO would work but the top fiber mix might pull free when glued? I believe that stuff is more for nailing and not gluing. Cheap Birch will delaminate as well.

"Do I just connect the speakon straight to the driver, and then wire a second speakon in parallel?"

Yes. Make sure you keep track of which pins you are using if you use 4 pole speakons! With 2 poles it's not a problem but make sure you also keep the polarity correct.If you wire 1 sub out of phase you're in for a surprise if you run them together!

Sydney · #54 Post by **Sydney** » Sat May 17, 2008 7:58 am

Your very welcome,
Also on the carpet this thread:
http://billfitzmaurice.com/phpBB2/viewtopic.php?t=2139

I've been trying to search for a chart of the T39 with dual
S2010s,

Don't know, I haven't got one & DJPHATMAN can't find his.
( He is the ONLY owner of a dual T39 with HL-10's that I am aware of. )

dual 10" drivers, the minimum width is 22", correct?

Seems reasonable - but I don't know.
Syd

David Carter · #55 Post by **David Carter** » Sat May 17, 2008 8:12 am

Ron K wrote:As far as wood goes the 1/2" Arucco Ply is 5 equal plys void free. It's strong and light weight and if you're building the slimmer versions should be just fine. For the wider versions you might want to use 1/2" Baltic birch.

My first cab was an Omni 10 which I built out of Baltic Birch--VERY strong and sturdy! By the time I got ready to build more, the price of BB had gone up so much that I got Arauco from Lowe's for my DR250's and T39's. It's lighter, and I had a little more trouble with warpage, but it was not a problem in the grand scheme of things because each piece was able to be pulled into place after gluing by using screws as recommended in the plans. The Arauco is a little softer and could be subject to a few more scratches and dings, but, if you're carpeting, that isn't an issue because they'll never be noticed. As for strength of the finished cab, the Arauco cabs are every bit as tough. I could jump up and down on my T39's all day long, and the only thing that would get damaged would be my knees (and I'm a 200 lb. guy)!

djwoo · #56 Post by **djwoo** » Sat May 17, 2008 12:00 pm

In all omni/omnitop plans it´s a guide to carpet, but not in all the others, if you are planning in made an omni/Otop get the plans and you can learn how to carpet; the guides in the plans are very easy to follow, and don´t forget the measure twice cut one rule, print a copy of the plans and keep it in your work area close to you. Always go triplay is stronger than mdf and resist humidity MUCH better, a mdf bafle with humidity is nothin more than sh&t.

DaveK · #57 Post by **DaveK** » Sat May 17, 2008 3:02 pm

It takes a LOT of carpet to wrap a Titan. It's also a PITA IMHO. After doing 6 boxes in carpet and hating it every time, I decided to take the plunge and switch to Duratex. I'm glad I did.

Frankenspeakers · Sat May 17, 2008 10:46 pm

Red: Your dad is right in one aspect- most speaker manufacturers do use mdf because it is cheap. Cheap covers a multitude of sins. MDF eats blades- even carbide, the fibers are hazardous and get everywhere. MDF also is very fragile and heavy so if you drop the heavier than plywood enclosure, it will break (the BFM cabinets are strong enough to park a car on). MDF looks bad unless it is painted or ratfurred you can't stain it and have it look like anything you'd be proud of... Most home speakers will sit in one place untill you move (it) to the next house or apartment (cussing all the way). The only redeeming quality of MDF is that it is cheap. I used MDF in my TT for some of the non-critical internal pieces that would not be seen or damaged, and it worked out OK for that, but I don't plan on moving it much- it's a coupl'a stone heavier than a 100% ply TT would be. You (at 20 years old and still presumably full of ... & vinegar) would still feel the extra weight during the 3am loadout! Depending on where you live and what contacts yer ol' man has with his suppliers, you may get a good deal on Russian (or Baltic) birch (stay away from the Chinee birch- it's some white mystery wood that is ok, but depending on which plant it's from the glue ranges from ok to piss-poor) Arouco and Radiata Pine are pretty much the same thing: south-american plantation grown pine and has a decent rep, but will warp more than BB. Just use extra clamps. If your dad wants to use biscuits thats ok, but don't use anything but PL to glue it up with wipe the edges with a wet sponge or rag- and make sure the bead goes all the way down the seam (most of this info is in the plans- but I'm making a point of it because experienced woodworkers can get a little opinionated and we are tellin' youse what we found to work ('cause we all have found out what don' work)

Now, back to your dad's opinion- these designs are light-years ahead of conventional speakers (unless you have the megabucks for top-tier EAW or Meyer gear) and these designs are every bit as good as the best, as long as you follow directions and your woodworking chops are fair to partly decent. PS, I have an old Fender Bassman ten combo amp that survived a few generations of Pete Townshend wannabees at a local highschool... under the torn tolex is plywood (mdf would not have survived). The speakers that are built to last are made with plywood.

EDIT: I almost fergot- fergit the ratfur and use Duratex. Ratfur is OK as a trunk liner or car stereo cover- but it ain't pro grade. People use fur because it covers a multitude of sins, but so does duratex!

REDLINE · #59 Post by **REDLINE** » Sun May 18, 2008 4:32 pm

Well everyone keeps talking about different kinds of birch, but I don't know how to find any of those. I stopped by the Home Depot to take a look, and all it said was just birch. A single 4x8 1/2" think sheet of "birch" would cost me $29.95. I have no idea what kind it is, but I figured that is what I would use.

As far as the rat fur goes, for some reason I really like it and I think it looks really professional. My old speakers weren't rat fur, and I thought they looked shitty (although maybe they weren't duratex cause they were really cheap), so I'll head on over to GC and ask what speakers are duratex so I can see what the material looks like.

pgolde · #60 Post by **pgolde** » Sun May 18, 2008 4:47 pm

The Home Depot "Birch" is NOT Baltic Birch, and has NO strength, you are better off with the Acuro. I have had the 3/4" Home Depot Birch break like it was made of Balsa wood, it really is not good stuff, whatever they make it out of, it's not Birch on the inside. Weak wood, full of voids is not worth half the price they charge for that Chinese garbage, spend an extra 10 bucks and get the real deal.