Rough design of possible first DIY speaker... (1 Viewer)

[NickSo]

Hey, so i've been wanting to get a pair of small bookshelvesspeakers for my bedroom, and just today started toying with the idea of building my own small enclosure for the Tangband 871's. I know they won't have much bass without a sub, but it should be fairly cheap to build.

Check out my design:



The two endcaps will be wood, the tube will be a sonotube (i THINK i saw them that small at Home Depot. Their largest is 12", and i know they have smaller sizes than that. If a 6" sonotube isnt available locally, i might consider PVC pipe.

The hole on the front is where the speaker will go. Since im not very experienced with woodworking, the endcaps might just be rectangle rather than rounded at the top.

I got the length of the tube doing some simple calculations finding out the volume inside the box of the Elf1.0 speakers from creativesound.ca.

One worry i have though, is cutting the peice of wood for the plug for the endcaps that goes inside the tube. I dont have a router, what other methods could i use to cut an approx 6" circle in a peice of MDF?

Anyhow, how does my design look? Feasible?

 

[GrahamT]

Looks original, but hard to make. You can cut circles with a jigsaw but it will be hard to fit the driver in without routering the inside edge.

 

[minhG]

you can also cut a rough circle with a rotary saw (like a zipsaw or high speed dremel) but a router would make your life much, much easier.

maybe graham is really good with a jigsaw, but i couldn't do it!

an alternative would be to find a woodworker in your area, he'd be willing to do the cuts for you. i can't imagine it costing very much either. a good alternative if you have no tools to work with.

 

[NickSo]

Hmm... i suppose for the 6" plug peice i could cut roughly with a jigsaw and sand it down...

as for the hole for the driver... i have a rotary tool, i guess if i took it slow i could do a decent cut, and maybe do more sanding. But then i'd have to be sawing through 2 layers of 3/4" MDF (the end cap + the plug) if i wanted an accurate cut (compared to the other alternative, cuttig both seperately then gluing together).

Are there hole saws as big as 3"?

I just realized Home Depot rents tools, maybe they have routers for rent?

Thanks for the feedback, keep 'em coming

 

[Wayne Ernst]

Yes, they sell hole saws 3" and even larger.

 

[ThomasW]

You can get them as large as 6" diameter. Note that if one that size binds in the hole, the spinning drill handle will break your wrist or arm.........

 

[minhG]

on cutting with a rotary saw, you need to do it really slowly, i usually do 1/4 or 1/3 an inch at a time and make multiple passes. this can be painfully slow if you have to cut a lot of circles. but if you're only doing 4, then it won't be too bad.

even with a router, you'll still need to do a little sanding and swearing because the sonotube will not be completely round.

i'm pretty sure you can get the 3inch hole saws at Home Depot, but i don't know how powerful a drill you need for those hole saws.

minimum size for me has always been bigger then 4"

 

[RobLJ]

Not to point out the obvious, but maybe it's time to buy a router. I'm at that same point too. I want to build a sub, but cutting out a 12" hole that looks decent and recessed is all but impossible w/o a router.

 

[minhG]

i dunno, i've made two sub woofer boxes (an 8" and now a 12") and used a rotary saw to do the cut outs for the driver. and they did a pretty decent job.

for the 8, i even doubled up the baffle so i could recess the driver.

if you already have the rotary saw and you don't plan on building too many more enclosures, then i say use what you got. if you have other uses for the router, by all means try to pick up a decent one. use a mediocre router is very frustrating...

 

[NickSo]

Yeah, im just your average university student, dont got much cash to splurge on power tools, though i do want, in the future, to build a sub, and that would be greatwith a router. But alas, a router isnt high on my 'to buy' list.

minh: what attatchment bit for the rotary tool did you use to cut with?

 

[Dave Poehlman]

Have you checked at Home Depot? They sometimes sell pre-cut circles. I don't know if they sell as small as 6" though... and you may have to settle for plywood.

I like your idea though, Nick. And you could build a sub to match.

 

[minhG]

nick,

for cutting the circles.

my ryobi came with a circle tool, basically you bolt on end to the rotary tool and the other ends pivots inside a pilot hole (which is the center hole of your circle). I don't know if other rotary tools come with something similiar. it actually works pretty well considering how simple it is, the only problem like i said is that you need to go slow and make multiple passes.

 

[NickSo]

Thanks a lot minh... ill take a look for that next time i go to home depot...

Dave: Yeah, i was just thinkin that, a side-firing sub, perhaps using the Tangband 6.5" subwoofer in that other thread That'd make a nice little mini-system hehe

 

[TimForman]

Seems like a hassle to build but it's unique and that's part of the fun of DIY. Whichever baffle shape you go with stick with your design of an offset driver. The recent issue of Audio Xpress has a comparison of "apartment" subs (around 20 liter Vb)and of the three 8" drivers they used the TB W8-704C gave better results.

 

[NickSo]

I dont know, the way im looking at it, i think its easier to build than a basic box speaker cabinet. I don't have the experience to really build a really good sturdy box from six different peices of wood.

This design is more like a mini-sonosub.

 

[TimForman]

You may want to add up your cost of materials and then compare that to getting some cabinets from Al Wooley.
http://quicksitebuilder.cnet.com/wrnch2/id26.html
or just go for the whole kit.
http://www.creativesound.ca/details....LF1.0DKCKCOMBO
Unless of course you really want to build it all yourself then the cost becomes secondary.

 

[Andy Goldstein]

i used a roto-zip to cut all the holes out for my double advents. quite easy, once you make a template. i cut out a circle of the correct size to make the woofer hole, taking into account the distance from the edge of the roto-zip guide to the edge of the "blade". i fastened the wooden circle to the baffle, using a drywall screw in the center of the cutout-to-be. the sawdust keeps the 3/4" mdf from falling through the hole. worked great!

ag.

 

[Dan Wesnor]

See if your school has a wood shop. Most do, but they're usually out of the mainstream.

 

[Kenneth Harden]

Not if you hold it like a man

If that was the case, my 12 amp 1/2" drive impact wrench and electric drill would have landed me in the hospital many times over

I plan on using a 4" hole saw for my 16 driver holes I need to make. MDF is predictable, so it should be easy.

 

[JamesP]

I've had a big hilti drill bind up on me while doing an asphalt core sample. It pretty much nuked all the tendons in my right wrist. Good times.

Home Depot will most likely have routers for rent. If not, there are tool rental places around most towns.