Bringin' Back the Boombox!

46K12763

Intro: Bringin' Back the Boombox!

What happened to the good ole days of taking the boombox out and listening to music with your friends, family, coworkers or the neighborhood on a sunny day?  It's all been lost to the iPod generation.  Too many people plug into their mp3 players and by doing so shut the world out.  They don't share their music and the world can't share music with them.  What a terribly antisocial platform!  It's time to bring back the social side of music!  Unfortunately the classic ghettoblasters are all gone, but you can follow this tutorial and build a no-frills, portable boombox that will play any 1/8inch stereo input (Walkman, CD or mp3 player).

STEP 1: Tools and Safety

Notice: This tutorial makes the assumption that you know how to safely use the power-tools and hand-tools listed below. Only use a tool if you can do so safely!

Notice: This tutorial requires you to do some simple soldering.


Safety goggles
Table saw
Band saw
Dremel
Dremel circle cutting attachment
Drill
Hammer
Wood awl
3/32 inch drill bit
1/8 inch drill bit
1/2 inch drill bit
2 or 3 bar clamps
Tape measure
Phillips head screw driver
Sand paper
12V trickle battery charger
Soldering iron
Solder
Helping hand (optional)
Wire Stripper
Crimping tool or pliers
Scissors
Permanent pen
Small flat-head screwdriver
Voltmeter (optional)

STEP 2: Material List

It is highly recommend that you use as much scrap wood and on-hand materials as possible. It shouldn't be too hard to modify instructions for speakers or an old bag strap you have laying around.  You might even consider cutting and stripping an old Ethernet or audio cable for the wire requirements.  In step 9, an old card is used as a mounting plate.  All these things add up to helping the environment and your wallet.


1 24" by 48" 5-ply birch plywood
1 24" by 24" 3-ply birch plywood
24 6x3/4"  wood screws
7-9 6x1/2" wood screws
2 208x1-3/8" screw eyes (buy local to make sure your strap's clasps will fit)
1 12V 4.5Ah sealed lead acid battery (closest I could find to the battery I use)
1 pkgIndustrial Velcro tape
1 spent gift-card
1 pairPioneer car speakers TSAA1372R
1 messenger bag strap
141hz AMP6-Basic (fully assembled)
1male to male 1/8inch stereo cable
4self-sticking cushion feet
1 2.5mm by 5.5mm by 9.5mm (size N) DC power plug
1 1ft lengths of red stranded 20gauge wire.
1 1ft lengths of black stranded 20gauge wire.
2 1/4" female disconnect terminals



STEP 3: Solder and Assemble Electronics

Tools for this step:
Soldering iron
Solder
Helping hand (optional)
Wire Stripper
Crimping tool or pliers

Materials for this step:
1 2.5mm by 5.5mm by 9.5mm (size N) DC power plug
1 1ft lengths of red stranded 20gauge wire.
1 1ft lengths of black stranded 20gauge wire.
2 1/4" female disconnect terminals
141hz AMP6-Basic (fully assembled)

Notice: Solder in a well-ventilated area.  Solder fumes are not good for you even if you use lead-free solder.


Solder the Power Plug:
3-A1. Get the 1 ft pieces of red and black 20guage wire.
3-B1. Strip 3/8in off both ends of each wire with the wire stripper.
3-C1. Unscrew the black housing from the DC power plug.
3-D1. Solder the red wire to the shorter tab and the black wire to the longer tab.
3-E1. Wait for the solder to cool, and slide the housing over the wires and screw it back onto the plug.


Attach the Terminals:
If you have a crimping tool:
3-A2. Insert a wire end of one of the wires into to the plastic end of a female disconnect terminal.
3-B2. Use the crimping tool to secure the wire to the terminal. (how to crimp)
3-C2. Repeat 3-A2 and 3-B2 for the other wire.

If you have pliers:
3-A3. Use a pair of pliers to remove the plastic insulation from a female disconnect terminal
3-B3. Insert the stripped end of one of the wires into to the narrow end of the female disconnect terminal.
3-C3. Use the pliers to squeeze the narrow end of the terminal until it holds the wire firmly.
3-D3. Solder the wire inside the narrow end like shown below.
3-E3. Let the solder cool and repeat steps 3-A3 through 3-D3.


Amp6-Basic:
3-A4. follow the instructions provided by 41hz to assemble and test the amplifier.

STEP 4: Cut and Prepare Box Pieces

Tools for this step:
Safety goggles
Table saw
Band saw
Hammer
Wood awl
Tape measure

Materials for this step:
1 24" by 48" 5-ply birch plywood
1 24" by 24" 3-ply birch plywood

Notice: Use a band saw to cut warped wood.  A table saw can catch in warped wood and throw it with deadly force.


4-A. Measure the thicknesses of the wood you use and put those dimensions in equations given below.  If you have any questions about this, please leave a comment.

4-B. Cut out and label each wood panel and strip according to the letter assigned below. These letters are used to refer to panels and strips in later steps.

[A] Top panel:
18" by 7" from the 5-ply sheet.
Refer to image below on where to mark center points for 7 holes.

[B] Front panel:
18" by 9" from the 5-ply sheet.
Refer to image below on where to mark center points for 12 holes.

[C] Side panels:
7" by (9 - [5-ply thickness] * 2)" from the 5-ply sheet
Refer to image below on where to mark a center point and drill one 1/8" hole.

[D] Bottom panel:
18" by 7" from the 5-ply sheet.
Refer to image below on where to mark center points for 7 holes.

[E] Rear panel:
(18 - [5-ply thickness] * 2)" by (9 - [5-ply thickness] * 2)" from the 3-ply sheet
Notice: Don't mark any center points for the rear panel until step 6.

Inset strips:
All inset pieces are from the 5-ply sheet.  Cut 1" strips from the long side of the sheet, then cut them with a miter saw.
[F]2  1" by (18 - [5-ply thickness] * 4)"
[G] 2  1" by (7 - [5-ply thickness] * 2)"                                             
[H]2  1" by (18 - [5-ply thickness] * 2)" 
[I] 2  1" by (9 - [5-ply thickness] * 2)" 
Refer to images below on where to mark points for holes.


STEP 5: Cut Speaker Holes

Tools for this step:
Safety goggles
Dremel
Dremel circle cutting attachment
Drill
3/32 inch drill bit
1/8 inch drill bit

Materials for this step:
[B]Front Panel


5-A. Drill 1/8" holes at the points labeled L1, L2, R1 and R2 in the image below.
5-B. Unplug the Dremel and read the instructions for the circle cutter.
5-C. Set up your Dremel with the circle cutting attachment.
5-D. Insert the center point in L1 and the bit into L2. 
5-E. Plug in the Dremel.
5-F. Turn the Dremel on to a setting of 7 or higher.
5-G. Apply a constant force to the Dremel traveling in a clockwise circle.
5-H. Too much force will stress the bit and may cause it to break.
5-I. Turn off the Dremel when you finish cutting the circle.
5-J. Repeat steps 5-D through 5-I for holes R1 and R2.
5-K. Sand both holes until splinters and burrs are removed. Don't worry if the hole isn't quite perfect. If the speaker fits in step 8, the hole is fine.
5-L. Drill the 8 remaining holes out using a 3/32" bit.




STEP 6: Attach the Insets

Tools for step:
Safety goggles
Hammer
Drill
3/32 inch drill bit
Wood awl
2 or 3 bar clamps
Tape measure
Phillips head screw driver
Sand paper

Materials for this step:
[B]Front Panel
[C]Side Panels
[E]Rear Panel
[F,G,H,I] Inset Strips
10 6x3/4"   wood screws
7-9 6x1/2" wood screws


Front Panel Insets:
6-A1. Flip [B] so that its back side (the worse looking of the two sides) is visible.
6-B2. Position a [H] according to third image below. 
6-C3. There should be a space between [H] and the edges of [B] that is the thickness of your 5-ply sheet.
6-D4. Clamp [H] to [B] to hold the spacing.  You may have to adjust [H] when you clamp down because the wood may have a slight bend in it that will come out as you tighten the clamps.
6-E5. Drill all 3 holes in [H] with a 3/32" bit to a depth of 3/4".
6-F1. Screw a 6x3/4" wood screw into each hole until the head of the screw is flush with or slightly below the surface of [H]
6-G1. Repeat steps 6-A1 through 6-F1 for the other inset on the back of [B]. The finished result is shown below.


Side Panel Insets:
6-A2. Flip a [C] so that its back side is visible.
6-B2. Position [I] according to the fourth image below. 
6-C2. The short edges of [I] and the sides of [C] should be flush.
6-D2.  The long edge of [I] should be spaced the thickness of your 3-ply sheet from the edge of [C].
6-E2. Clamp [I] to [C] to hold the spacing.
6-F2. Drill both holes in [I] with a 3/32" bit to a depth of 3/4".
6-G2. Screw a 6x3/4" wood screw into each hole until the head of the screw is flush with or slightly below the surface of [I]
6-H2. Flip the other [C] so that it's back side is visible.
6-I2. Position [I] according to the fourth image below.
6-J2. Repeat steps 6-C2 through 6-G2.  The finished results are shown below in the fourth image.


Rear Panel Insets:
6-A3. Flip [E] so that its back side is visible.
6-B3. Position the long edge of [F] to be flush with [E].
6-C3. The space between the short edges of [F] and the side of [E] should be the thickness of your 5-ply sheet.
6-D3. Clamp [F] to [E] to hold the spacing.
6-E3. Flip [E] so that its front side is visible.
6-F3. Drill the three 3/32" holes along the edge to which [F] is clamped (holes 1,2,3 or 5,6,7) to a depth of 1/2".
6-G3. Screw a 6x1/2" wood screw into each hole until the head of the screw is flush with the surface of [E].
6-H3. Repeat steps 6-B3 through 6-G3 for the other inset on the back of [E]. Your work so far should look like the fifth image below.
6-I3. Look at the last image below. If your wood is curved like in the image or has no curve, skip step 6-J3.
6-J3. Mark and drill out holes 10 through 13 on [E] with a 3/32" bit  (see the sixth image below). Skip step 6-K3.
6-K3. Mark and drill out holes 8 and 9 on [E] with a 3/32" bit (see the sixth image below).
6-L3. Set a [G] inset between the [F] insets already attached to [E].
6-M3. Make sure [G] is not flush with the short edge of the [F] insets, it is offset by about 1/16" (see the first image below) then clamp it to [E].
6-N3. Screw a 6x1/2" wood screw into the hole(s) until the head of the screw is flush with the surface of [E].
6-O3. Repeat steps 6-L3 through 6-N3 for the second [G] inset.

STEP 7: Assemble the Box

Tools for this step:
Safety goggles
Drill
3/32 inch drill bit
1/8 inch drill bit
2 or 3 bar clamps
Phillips head screw driver
Sand paper

Materials for this step:
[A]Top Panel
[B]Front Panel
[C]Side Panels
[D]Bottom Panel
[E]Rear Panel
14 6x3/4"   wood screws
2 208x1-3/8" screw eyes
4self-sticking cushion feet


Bottom to Front Panel:
7-A1. Drill all the holes on [D] out with a 3/32" bit.
7-B1. Set the long edge of [D] that has the holes 1,2 and 3 that you just drilled along the bottom inset inset of [B]
7-C1. Position [D] so it's edges are flush with the edge of [B]
7-D1. Clamp [D] to [B]. Make sure the edges remain flush.
7-E1. Screw [D] to the inset on [B] starting with the center hole.


Top to Front Panel:
7-A2. Drill all the holes on [A] out with a 3/32" bit.
7-B2. Set the long edge of [A] that has the holes 1,2 and 3 that you just drilled along the top inset inset of [B]
7-C2. Position [A] so it's edges are flush with the edge of [B]
7-D2. Clamp [A] to [B]. Make sure the edges remain flush.
7-E2. Screw [A] to the inset on [B] starting with the center hole. Viewed from the side, the box should now look like first image below.


Right Side Panel:
7-A3. Position [C] such that the side with inset is facing away from you, and the inset to your right.
7-B3. Measure and mark the only hole for [C].
7-A3. Drill the hole out with a 1/8" bit.
7-B3. slide [C] in flush.  The inset should be on the interior of the box and toward the rear.  The right edge of [C] should be flush with rear edges of [A] and [D].  The outer face of [C] should be flush with the short edges of [A], [B] and [D].
7-C3. Clamp [C] to maintain this position.
7-D3. Screw the side panel in using 6x3/4" wood screws in holes 4 and 5 on [A] and [D].


Left Side Panel:
7-A3. Position [C] such that the side with inset is facing away from you, and the inset to your left.
7-B3. Measure and mark the only hole for [C].
7-A3. Drill the hole out with a 1/8" bit.
7-B3. slide [C] in flush.  The inset should be on the interior of the box and toward the rear.  The left edge of [C] should be flush with rear edges of [A] and [D].  The outer face of [C] should be flush with the short edges of [A], [B] and [D].
7-C3. Clamp [C] to maintain this position.
7-D3. Screw the side panel in using 6x3/4" wood screws in holes 6 and 7 on [A] and [D].


Back Panel Fit:
The insets on [E] may not immediately fit into the back side of the box.  If this is the case, sand down the sides to produce a snug fit.  Do your best to identify the points that are catching and sand those first.  If there is a large amount of material that has to be removed, use a heavier grit sandpaper first then follow up with a medium or fine grit to finish.

If the back is too loose to stay in on it's own, try using a thin layer of wood putty on the insets of [E].  Let the wood putty set and dry completely then retry the fit.







STEP 8: Mount the Speakers

Tools for this step:
Phillips head screw driver

Materials for this step:
1 pairPioneer car speakers TSAA1372R
8 Speaker mounting screws (in the speaker package)


8-A. Remove the speakers from their packaging if you haven't done so already.
8-B. Follow the instructions on the box to attach the wires that came with the speakers to the speakers.
8-C. Set the boombox on a steady level surface with the front facing up and the bottom panel [D] facing toward you.
8-D. Take the speaker with the white cables and place it gently in the left hole
8-E. Position it so the Pioneer brand is to the left and the 3/32" holes in the wood are visible between the mounting tines of the speaker.  See the second image below.
8-F. Set the speaker face place on the speaker.
8-G. Align all the holes in the faceplate with the holes in the wood. See the third image below.
8-H. Set a screw in one of the holes and give it 4 to 5 turns to get it started firmly into the wood.
8-I. Set a screw in the hole opposite the previous one and and also screw it in until firmly in the wood.
8-J. Repeat steps 8-H and 8-I.
8-K. Turn each screw until it just makes contact with the faceplate.
8-L.  In a clockwise circle, give each screw a single turn until all screws are snug.  Over-tightening may crack the faceplate.
8-M. Take the speaker with the gray cables and place it gently in the right hole.
8-N. Position it so the Pioneer brand is to the right. and the 3/32" holes in the wood are visible between the mounting tines of the speaker.
8-O. Repeat steps 8-F through 8-L.  See the fourth image for the fully mounted speakers.

Notice: Be careful handling the box now.  The speakers on the front side if it may make it a little easy to tip until you get the battery in.



STEP 9: Make the Amplifier Mounting Plates

Tools for this step:
Scissors
Permanent pen
Drill
1/8in bit

Materials for this step:
Spent gift-card
Tape
Scrap wood


9-A. Find a spent gift-card.
9-B. Tape it to a piece of scrap wood. Leave a 1/2in by 1/2in section uncovered on each corner.
9-C. Use a sharpie to make a mark in the middle of one of the exposed corners of the card.
9-D. Measure 5cm to the nearest exposed corner and make another mark as close to the center of that area as possible.
9-E. Repeat 9C and 9D for the unmarked corners.
9-F. Drill an 1/8in hole in each marked point.
9-G. Remove the tape holding the gift-card to scrap wood.
9-H. Cut a 1/2in section off each end of the card.

STEP 10: Mounting Amplifier and Battery

Tools for this step:
Scissors

Materials for this step:
141hz AMP6-Basic (fully assembled)
1 pkgIndustrial Velcro tape


Attach Mounting Plates:
9-A1. Put a mounting screw through the top of one of the mounting holes in the amplifier.
9-B1. Put a nylon spacer over the screw.
9-C1. Put one of the holes of one of the gift-card ends over the screw
9-D1. Thread a bolt on the end of the screw and tighten it with your fingers
9-E1. Put a screw through the nearest corner mounting hole in the amplifier.
9-F1. Repeat steps 9-B1 through 9-E1 using the other hole in the gift-card section.
9-G1. Repeat steps 9-A1 through 9-F1 for the remaining 2 mounting holes.


Velcro the Battery:
9-A2. Adhere an entire hook patch of Velcro to the back-side of the battery. See the second image below.
9-B2. Place an entire loop patch on the hook patch
9-C2. Remove the backing from the loop patch. See the third image below.
9-D2. With the terminals facing the rear of the box and the Velcro facing down, place the battery between the speakers and at least 1in from the back edge of the box. See the fourth image below.
9-E2. Press firmly on the battery so the loop patch adheres well to the wood.


Velcro the Amplifier:
9-A3. Cut out 2 hook and 2 loop patches of Velcro that are 1in by 1/2in.
9-B3. Adhere a hook patch on the bottom of each mounting plate between the screws.
9-C3. Place a 1in by 1/2in loop patch on both hook patches.
9-D3. Remove the backing from the loop patches.
9-E3.  With the stereo jack facing the rear of the box, place the amplifier with at least 1in of space on all 4 sides. See the first image below.
9-F3. Press firmly on the back side of the mounting plates so the loop patches adheres well to the wood.


STEP 11: Connect Electronics

Tools for this step:
Small flat-head screwdriver
Voltmeter (optional)

Materials for this step:
Power plug
1male to male 1/8inch stereo cable


Speaker Wires to Amplifier:
11-A1. Pull off the short pieces of sheathing from the ends of the speaker wires. 
11-B1. Use your fingers to twist the copper strands into a tight spiral
11-C1.  Insert the striped wire of the left speaker (when you're facing the front of the boombox) into the left negative screw terminal on the amplifier.
11-D1. Screw down that terminal until the wire is held firmly.
11-E1. Insert the solid-colored wire of the left speaker into the left positive screw terminal on the amplifier.
11-F1. Repeat steps 11-C1 through 11-E1, replacing all instances or 'left' with 'right'.
11-G1. If you turn on the amplifier later and notice the channels are switch, open up the box and switch the left and right speaker cables.


Battery to Amplifier:
11-A2. Follow the directions of the battery charger to fully charge the 12V battery you are using.
11-B2. Connect the red wire to the positive terminal of the battery.
11-C2.  Connect the black wire to the negative  terminal of the battery.
11-D2. If you have a voltmeter, double check that the center of the power plug is connected to the positive terminal of the battery.


Connect Music Device:
11-A3. Plug one end of the 1/8" stereo male to male cable into the amplifier.
11-B3. Feed the other end through the hole in the back panel.
11-C3. Plug the other end of the cable into your music device.

STEP 12: Turn Up the Music!

12-A. Turn your music device's volume to zero.
12-B. Connect the power plug to the amplifier.
12-C. Close the back of the boombox.
12-D. Turn up the volume!If everything is connected correctly you should here audio coming through with no popping, hissing or cutting out.  If this is not the case or things do not sound right to you in any way, unplug power to the amplifier immediately and review Steps3 and 11 and double-check your work and correct any errors you've made.
12-E. Go to the beach, park, tailgate party and share your favorite music with your new boombox!
12-F. When you are done listening to music, be sure to unplug the power from the amplifier.

63 Comments

could you use a 12 volt wall power adapter to power it?
You can. Make sure the 12V adapter's current rating is high enough for the amp.
i found a 12v adapter laying around that fit and plugged it an, nothing worked. Sorry im kind of a newb, but managed to build the thing, im just waiting on a charger to charge the battery...thats why im wondering, what form is current rating in, is it mA?
head to this website, its kinda the same thing and should have all the info you need
http://www.ehow.com/how_4448174_subwoofer-computer-home-theater-system.html
and how many mA's are required for this amp?
There is a symbol on the adapter that shows the polarity of the inside and outside of the plug. You want an adapter with the center positive. I have another 12V t-amp that is slightly smaller that requires a 2000mA (2A) adapter. I hooked up the amp6 to that adapter and it works fine. Just probably best not to crank it or make sure the adapter doesn't get to hot.
I was thinking of making a similar project, but have very limited knowledge with lead acid batteries.
All I know is you have to use the sealed lead acid deep cycle(leisure/golf cart) type.

As I heard when charging lead acid batteries that hydrogen gas can build up and it can be very dangerous in an enclosured area.

So preferably I guess It's wise to have a removable back to the boombox enclosure and take out the battery/batteries to charge them.
And I'd use a smart charger just to be safe.

Also when the amp is inside the enclosure, doesn't it overheat though?
As amps that I seen that are mounted inside wooden or plastic enclosures are usually the plate amp variety.
And have a heatsink and large metal plate on the outside back, sometimes with extra heatsink fins.

Anyway I like the construction of your box and the way you attached the battery.

I'd put a speaker protection module(to protect against switch on thumps, amp going DC,etc) in between the the amp and the speakers though like this one:
http://connexelectronic.com/product_info.php/products_id/71?osCsid=qcr5h8phhtp80kmusjq2s5a0q7


what is the make and name of that mp3 player ????
It's a Cowon D2. I've had it for a few years and I love it.
thanks
Ok, like I already said I am a complete newb, I got the amp6, not the basic, the one that comes already assembled. Anyway, I plugged everything in and nothing happened, so I looked on the 41hz website and it said i need to add a transformer 12 to 15 VAC or 16-20VDC. What does that mean? I know i got a part in the box the amp came in, I had no idea what it was so i put in in a drawer, do I need to solder this onto the amp or something like that?
I'm sorry, I don't know the answer to this. 41hz seems to have an active forum for the amp6.  You may be able to find an answer there. Best of luck!
How long works the Battery whit full power?
I'm not sure, but I just spent a week working in a machine shop and was able to play it at maybe 3/4 power for 6 to 8 hours a day. I would imagine full power would last at least a couple hours.
It's quite a nice idea you have there! However there might be some aspects that could be improved further:
-I don't think keeping both speakers in the same box without any kind of separation is a good idea. They tend to cause interference with each other that'll worsen the sound quality
-The interior of the box could really use some dampening too, for the same reasons as above. Plus both sides of the speaker produce vibrations, but the reas one's phase is shifted by 180° i.e. inverted, so if such waves combine they'll cancel each other out.
-I've checked out the amplifier's and the speakers' specs and have to say that the speakers are an overkill for the amp. You see the speakers are WAY more capable than the amplifier is: they can do 50W RMS and up to 250W max (that is for music you'd be pretty safe even with a 150W amp), yet the amp is capable of only half the RMS value at most, 25W and only with 10% THD (amount of distortion, for music it's WAY too much). The maximum power for 0.1% THD or less (which is way more acceptable :P) is 15W, which isn't a lot. So if you're worried about battery life, you can keep your current amp. But if you want to get the maximum out of your box, you might want to consider getting a more powerful amp. A 150W one would do. Keep in mind however that you'd have to add at least another battery for increased voltage and even then they would be discharged pretty fast. Actually 4 batteries or a transformer would be preferred. You'd also have to insert a bigger heatsink. But still, it's up to you, as I said.
I strongly recommend you doing at least the first two things (separate the speakers and dampening). Good luck ;)
Thank you for your suggestions.  When I paint it this summer, I will add a separator between the speakers and line it with a dampening material.

The technical details in the Amazon article are incorrect, these speakers are actually 35W rms and 180W instantaneous max.  They're still overkill, but I'd rather have it that way because I can safely crank my current amp all the way without worry of damaging the speakers.  At half volume the sound quality is pretty good and the volume good for comfortable outdoor listening.  At max it does distort heavily, but when I crank it up to max I'm not looking for fidelity anyway.
Sorry buddy, not quite so.

Its rather hard to kill speakers by putting to much music power through them, as its all AC and comes in peaks (which is how there is such a huge difference between rms and pmpo). but when your amp distorts, your chopping the curve of your wave out, flat-lining your signal, aka DC. the speaker stops moving, and so all the power your feeding the speaker goes as heat. which is baaaaaad, and kills speakers. its far easier to burn out big speakers with a small amp than burn small speakers with a big amp (although you can make them rip 'emselves to bits, which is fun).

the moral of the story is distortion is bad and not healthy for your kit, please don't do it.

*rant*
I personally believe that heavy musical distortion (obvious caveat for guitar distortion, which is similar but not the same) is a horrible, evil thing to do, especially in public. If I was Supreme Overlord of the Universe, I would make publicly playing distorted music punishable by perferation of the eardrum and bludgeoning the offender with the offending device until one of them is broken. in the case of a mobile phone, where perforation and boot assisted rectal insertation may be performed.
*/rant*

ahem. CoolKoon knows what I mean im sure.

if its not loud enough, get a bigger amp. personally, I'd go for about 50w turned down (less heat), using a pair of 'chip-amps', either as a kit or built 'dead bug' style, using 2 identical batteries for a +/- 12v supply, or 4 for a +/- 24v if you really wanna bust some serious noise.

If your not up for building the amp, id be looking around pawn shops and car wreckers for an old little car stereo amp, again about 50w. their not common any more as mosfets make most head units capable of this, but an old transistorised external one should be able to be found for pretty cheap.

all up, great idea, bring the beat back. theres a dude who wanders around my city listenin to reggae/dub thru a boombox (not to loud, with respect), and gets alot of props. Freo's a pretty cool city like that
I definitely do :D

<rant>
There's something even worse that has began to take roots recently with the advent of phones with "stereo" speakers: ignorant kiddos (well, teenagers, but that doesn't make a difference) use their phones to conjure up some "background noise" while they're gathering in groups. Since the sound's actually devoid of bass, it's literally nothing more than some nasty background noise....
</rant>

I haven't thought about the distorted sound that way, but it actually makes sense. And you're right, burned wiring means you can pretty much throw out the speaker (although I've seen some recoil kits at my local audio store....).
I didn't want to bring up the PMPO issue because there doesn't seem to be a consent even amongst professionals whether the value's relevant, meaningful and comparable at all. But I still think that you might get away with a more powerful amplifier (>50W RMS) for this speaker, as long as you'll use it for music (where the output, amplitude and power in general is constantly changing, thus reducing the risk of overload).
As for the amp itself, if you're not afraid of using a soldering iron, you can buy some amp kits just about everywhere with all the necessary parts included. All you have to do is to solder everything together according to the instructions and take care of the power supply.
yaha. thats why they get the special deluxe boot treatment. I wear size 12's. and I like hiking boots. with lots of knobbly bits. and buckles. how i long for sweet revenge. sigh. *inserts deep-ear-buds* huh, what?

anyway, back to the real world of getting some sweet, clean sounds over your shoulder so you can blast those lamers off their feet with your epic phat bass.

the biggest issue with PMPO is there is no standard, it isnt relevant to *anything*, its just a number (unless they tell you what signal they feed and how long it will last before death, and even then nobody else will use that signal and that period). RMS is very defined, so you cant get it wrong. how much power you can push through a speaker, at the real world cutting edge, is completely different depending on the source track. listening to lounge jazz will have a completley different fail point than listening to dubstep. go figure.






oh yeah, forgot to add,

If anybody out there is planning on going the DIY amp route for this project, remember a pretty significant cost saving can be had in the power supply department. The rail filter capacitors are one of the most expensive parts of an amp, along with the transistors and heatsink. they sit between the rectifier and the amplifier to smooth out the 100/120hz (twice the grid frequency, and very audible with undersized caps) ripple which is inevitable when using grid power. As this project is designed around a battery, which inherently supply pure DC. so no (or very much smaller) ripple caps are needed. 

at 10-30 AUD a piece, and typically 2 required (for a dual rail supply), Doing It Yourself and choosing to underrate these could make the project a whole lot cheaper. If thats your primary objective. of course, leaving them in wont hurt anything.

that said, car audio shops always have huge 1F caps for sale for attaching to subwoofer amps. I think this is to reduce the instantaneous current surge through the long power leads that typically run from the engine bay to the boot, which would decrease the volt drop and therefore improve peak maximum power from the amp. that's only a theoretical explanation tho, ive no experience in that field of toys.

amirite?
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