/diy/ - Do It Yourself

>>9639
You are essentially just wiring the speaker backwards, and mounting it in/on some sort of stand. The modified drum shell serves to protect & isolate the speaker, making it easier to use. If you know how to properly wire in your own hardware (direct boxes, attenuators, volume control knobs, etc), go ahead. The simplest way to turn a speaker into a microphone is to wire positive to positive (pin 2 on an XLR, tip on a 1/4" TRS plug) and negative to negative (pin 3 on an XLR, ring on a 1/4" TRS). Mount it in any way you see fit.

>>9657
But that version is boring. I went as far as to repaint my snare drum and make a shock-mount. Remember, if you're going to be using this thing as a microphone, you want to make sure you can distinguish it from everybody else's gear. It should be able to say "this is my microphone. There are many like it, but this one is mine. If I catch you trying to steal it, I will hunt you down and murder your children... and eat them." In fact, write that on the side of the drum shell. While you're at it, draw some really obnoxious symbols on it to ensure that nobody would be caught dead trying to steal it: glow-in-the-dark neon pink unicorns should do the trick.

Yamaha makes their SubKick microphone for about $400, mounting a 6" speaker inside a 10" drum shell. Looks pretty, but it's overpriced.

I made a pair out of parts I scavenged from around house: I invested about $30 of new parts into building mine, most of which I didn't need anyway. Overall, mine is bigger, better, and much cheaper.
http://pro-audio.musiciansfriend.com/product/Yamaha-SubKick-LowFrequency-Capture-Device?sku=444623

>>9668
The idea behind this is to make it out of stuff you probably have lying around the house (assuming you're a musician), with minimal cost. Here's how I built mine.

TOOLS:

Soldering Iron (at least 30 watts)
Rosin-Core solder (don't use acid-core if you're dealing with circuit boards)
screw driver
drum key
drill (standard assorted wood bits: you may need a 3/4" to 1" wood bit)
scissors
measuring tape
Scalpel/razor blade/knife

and if you want to get creative,
sander
router
paint brushes (medium size and fine detail)


MATERIALS and where to find them:

>>9681
12" speaker (pic above)
1 functional speaker (not blown out), at least 6" diameter (bigger is usually better for our purposes: mine used a 12" speaker salvaged from an extra guitar amp). If you have a pair of monitors with a blown speaker, use the good one: a lot of recording studios used Yamaha NS10 cones when one of theirs blew out. Amps & subwoofers work too.

>>9697
14x5.5" Pearl Export snare drum
1 (preferably wood) drum shell: snare drums work well. remember, it needs to be larger in diameter/depth than your speaker. I used a 14"x5.5" Pearl Export snare, but a 6.5" depth may be easier to work with, depending on the speaker. IMPORTANT: notice how the hardware attaches to the side of the drum on that shell. Two bolts/holes for each piece of hardware: one bolt by each rim of the shell. This design will make mounting the speaker easier in most cases. Also a drum with 8 lugs (or even 4 for that matter) will be more convenient when building the shock-mount.

1 snare drum stand

>>9711
Nuts, bolts, washers, rope, male XLR jack
1 standard XLR microphone cable (I used an old Switchcraft male XLR jack and some scrap Belden 8451 cable - balanced audio cable). Some people use an unbalanced 1/4" plug (guitar cable) and plug straight into an external direct box - whatever is more practical for you.

2 mesh drum heads, or two regular drum heads & some speaker grill cloth

A few feet of rope (small enough to thread through the screw holes on the speaker)

half a dozen bolts, nuts, & washers (to mount the XLR jack, if you're using one)

If you want to get creative, paint/stain & varnish: one color to base-coat or stain, another to write on your name. For the fine-detail work use some thicker paint (I used acrylics) that won't run. Spray paint if you're lazy.

1 postcard

tape (scotch or electrical)

zip ties

some foam (destroy some old cushions or something)

>>9725
Preparing the Shell.
Since I wanted mine to stand out (i.e. I don't want anybody 'accidentally' walking away with my new toy) I decided to paint my name onto it. Since I also decided to mount an XLR jack onto mine, I had to drill a few holes first: better to do this before you paint in order to make it look nicer. NOTE: if you actually want to keep the shell intact, you can just as easily slide the mic cable through the riveted vent in the side of the shell: just remember to have the male end sticking outside of the shell when you're ready to solder. Skip ahead if you don't want to bother painting/stenciling the shell.

>>9738
Take off all of the hardware, sand off any glue residue (leftover from the shell wrap) and drill your holes. As you can see, the 3/4" hole is a bit lopsided. This is because I had the bright idea of using the existing vent as a pilot hole. It is usually too wide to keep a large (flat) wood drill bit steady, so you're better off drilling a fresh hole. Attach the jack now (loosely) to see if you need to make any adjustments. If all is well, take off all of the hardware so you're left with the bare wooden shell.

>>9751
PAINT IT BLACK (or neon pink). I used a "Water based (oil modified)" stain for mine. Lay down some newspaper and follow the directions on the can. As soon as I set the can on the table, my German Shepherd knocked it over, staining the floor of my garage. A little stain goes a long way, so I actually had enough left over to finish two drum shells with the dregs - two coats.

>>9762
Since you're going to want to put some sort of identifying name/logo/symbol/etc on the shell, make a stencil so you can reuse it. I made my design with Adobe Illustrator along with a stencil font modeled after the the band Crass - fitting for a low-budged DIY project... because fuck you, Yamaha.
http://www.dafont.com/crass.font
Remember, you're making a stencil, so closed letters & symbols like A, B, D, O, P, Q, R, and so on need to have the breaks & openings.

>>9780
I made this to fit in between the lugs, centered over the XLR hole, so the dimensions will vary depending on the size of your shell.

Print it out, and clip it on to a postcard (something sturdier and more moisture-resistant than paper - just as long as it's still flexible)

Buddy, I hope you are at least using a high frequency capacitor in parallel with that. Just so you let high frequency waves float through the capacitor and the low frequency waves pass through the speaker.

>>9793
When you're ready, attack the paper with a scalpel until the postcard underneath looks like a functional stencil. Try to be neat, you don't want to ruin the stencil: otherwise, you'll have to do it all over again. This part can be very time-consuming, especially when the stencil for the other mic reads "THIS SPEAKER-MICROPHONE IS PROPERTY OF THE LOS ANGELES VALLEY COLLEGE RECORDING STUDIO"

>>9812
Tape it to the shell (mask off the rest of the shell with newspaper if you're going to use spray paint), and get your paint ready: remember, you want to use thicker paint for this, so it doesn't form a runny mess underneath the stencil.

>>9826
Basement-dwelling Warhammer nerds, put those painting skills to use. I'm going to paint this red, but I'm painting on a coat of white(ish) in order to make the red more vibrant, since acrylic paint will actually show some of the color beneath it (alternatively, if you're trying to make the letters darker, use a darker color underneath). It's actually better to paint the lighter undercoat in the center of the stencil (avoid the edges of the letters so you don't have a white outline around your red letters).

>>9829
Since it's a black shell, you can fix any mistakes with a sharpie. Or, fuck it, just use spray paint. When you're done, paint on a coat or two of varnish to protect everything. Let the paint/varnish dry.

IF YOU DIDN'T WANT TO BOTHER PAINTING THE SHELL, START HERE.

Mounting the speaker.

Some people have routed out the center of a circular piece of plywood, cut/sanded to fit inside the shell, but our rope method will function as a shock-mount, without damaging the shell. Depending on the size/weight of the speaker, you may be able to get by with bungee cords more effectively, but ours is too large & heavy for that.

Attach all of the hardware (minus the snare strainer/bracket, etc. Set the rims aside for now) - just the lugs, tightened on halfway so the bolts/washers stick out inside the shell.

Lay the shell down on its top, and prop up the speaker so the front lines up with the first set of bolts sticking inside the shell: books, magazines, etc, just as long as the pressure is on the outside frame of the speaker, not the cone itself. If your drum has 8 lugs, line them up with the 4 screw holes in the speaker. Try to line up the terminals on the speaker with the XLR jack or vent hole (if you didn't mount the XLR jack). Once the speaker is centered at the right height, grab your rope.

>>9841
Tie a knot in one end, and thread it through the screw hole in the speaker

>>9852
Tie a knot in the other end, wrap it around both lugs, and adjust it so the speaker is suspended in the center - not touching the shell. When it looks right, use a zip tie to lock the rope in place, and tighten the lugs down on the rope. Repeat on all of the other three lugs, opposite side first.

>>9863

Use the other 4 lugs to support the back of the cone, making sure that the upright speaker is completely parallel to the rim of the shell.

>>9881

Time to solder the wires into place. (XLR diagram above, won't let me repost)

If you aren't using an XLR jack, now is the time to chop your microphone cable in half - use the male (pointy) end and feed the wire through the vent (which should be more or less lined up with the terminals on the speaker), letting the plug hang outside the shell. Try to secure the cable on the inside of the shell so you don't rip the wires out by accident.

>>9919

My speaker came with a ground wire attached (screwed on) to the frame, so solder it to the ground (pin 1) if you have one.

Before you attach the heads, hook the speaker-mic up to a mixer and tap/talk into the cone: it should be working.

Take a piece of foam, and trim it to fit behind the cone: the foam should be able to hide flush inside the shell.

>>9936
From another speaker, going straight to an XLR: positive to positive, negative to negative: no ground present.

>>9946
If you have mesh heads, go ahead an attach them. If you need to make you own, cut the center out of some old drum heads (leave the portion that makes contact with the rim) trim/lay down the speaker grill cloth, and tighten the heads on over them, front and back.

You now have your very own speaker-microphone capable of capturing bowel-moving low end frequencies. Throw it in front of a kick drum (usually a few inches to a foot away from the resonant head) along with another microphone on the beater to pick up the full range of the drum.

>>9960
The finished product.

Engineers have been making these in the studio for years, so each one will have its own unique sound. If you get a chance, try to A-B them with & without the shell: just remember that it has a figure-8 polarity pattern, so it captures sound from in front and from behind the cone.

You may also want to consider adding an in-line pad, direct box, etc. Enjoy!

please provide a document with all of this saved and uploaded to megaupload.

>>9806
On my first few uses (through a tube preamp), I just threw on a pad, low-pass filter/simple EQ on the console. This mic was mixed in with another mic on the beater in order to get the full attack/low end (since this mic is all bottom-end, it sounds like shit on its own, but other mics can't pick up those kinds of lows).

Every other engineer I've lent this to for a session as usually ended up sound-replacing the other mic, and keeping this one of the low end.

If/when I get around to making another, I'm going to add some more features.

>>10122
Haven't gotten around to that part yet, but here's a more permanent link:

http://www.facebook.com/note.php?note_id=396381695993

There's actually a ton of these kinds of mic schematics all over the web. When I made this one about a year ago, I got a lot of info & inspiration from the guys over at GearSlutz.com

I got a bit of reference from this one too.

http://www.instructables.com/id/SPKR-MiK--How-to-make-a-microphone-from-a-speaker/

Lots of extra bells & whistles: built in DI and whatnot, definitely worth a look.

I attempted to consolidate all this

>>11572
Thanks. I'll see what I can do about getting this info onto megaupload or rapidshare. Worst case, it will be up by tomorrow.