Pictures of ear raid sound systems
 To the right:
Baby Carriage P.A. Battery in front, amp in wood box, sub box underneath.
baby carriage was $12 at value village.
Below:
We covered the pram with a cloth so it looked like we were walking a kid.
sheet was $1 at value village
 
To the Right:
Two Technics 80w 8 ohm speakers. they pound with the 4/8 ohm amp i use.
They were $24.95 at value village plus $3.99 for black spraypaint and i
found the metal mesh i screwed on the front of them.
Top one is the sub, 200w 8 ohm 12' technics sub speaker,
$20 from 2nd hand store, has speaker grille made out of ikea shelf.
 Above: This is a 140w two / four channel p.a. amp in box i traded for old RAM 5 yrs ago,
metal case $20 canadian tire, inverter $30 pawn shop, battery free,
case free. same $20 speaker as pic above
To the right:
free peavey guitar amp box, 2 150w 4 ohm speakers $100, 300w 4 ohm amp $25 from stereo repair store.
Battery is intended to be wheelchair battery in bottom of guitar amp case.
note that this is a full size 2x12 guitar amp box, just a small pic.
2 8 ohm 60w bookshelf speakers from value village $14.99.
metal grill made from mesh found onside of the road.
amp battery and inverter in bike trailer p.a. from other stuff above.
Wires:
You can use lamp cord. Take it out of the garbage or buy a lamp from a thrift store. Lamp power cord works just as well as speaker wire (http://www.roger-russell.com/wire/wire.htm), and the price is right. For p.a. power wire, I use extension cord cuz its got 3 wires (one for power switch on the remote power in) but lamp cord will do fine.
lamp cord will have polarity (+ and -) indicated by writing on one wire or a course texture on one side or a stripe or something. Look for wire that has this, you dont want wire that doesnt indicate that one side is different from the other.
total cost: free - $5?
Car Amp:
Any cheap car amp will do provided its 100 watts. Car audio manufacturers are total bulshitters. A Sony "1200 watt" amp from canadian tire is about $200-300. Now the thing is resistance (ohms).
1200 watts sony is tryin to pimp is actually like 200. here's how.
1200 watts at 1 ohm is 600 watts at 2 ohms is 300 watts at 4 ohms is 150 watts at 8 ohms.
the more ohms (resistance), the lower the watts. Car stereos are 90% 4 ohm. most amps will say their reccomended speaker impedance (thats ohms) somewhere on them. If not it will be 4 ohms cuz thats what car amps usually are. 8 ohm speakers will be quieter on an amp designed for 4 ohm, but they will still work.
note! old car amps by realistic and stuff with wierd eqs on them or just look old with a bundle of wires are not worth using. they are designed to boost a speaker level signal by another 30 watts. this means that the speaker outputs from your 8 track went into them and got a small boost in signal. you need one amp to do the whole job not a string of obsolete amps.
A good place to look is a pawn shop. A beater car amp could be $50. you can get them for $20 at value village but usually they are more
problematic. A pawn shop usually tests them or warranties them, so make sure you TRY THEM QUICKLY.
total cost: free - $50? get a cheap one first then once you know what youre doing, upgrade it.
Testing a car amp:
Keep a cheap speaker around that you know works, use it to test your car amps. one from a car door or something is fine, it just needs to be 4 ohms and make a sound when plugged in.
- strip lamp cord or extension cord.
- attach black (negative) wire to "ground"
- white / red / turquoise (positive colors for extension cord) or + (one with writing on it or rough texture - lamp cord) go to "remote" and "12v" in
please note that remote is supposed to go to the ignition, but if you just plug both remote and 12v in, the amp will be on until unplugged.
NEVER TOUCH BOTH POLES OF THE BATTERY AT THE SAME TIME.
NEVER CONNECT + AND - BACKWARDS
- attach test speaker to speaker output terminals, making sure to follow + and -. it doesnt matter if you only test one side if its a stereo amp (ex. plug left output into speaker only) as long as you test the other side afterward.
- attach discman or some other audio source to input. Use the rca inputs to plug in the source. (otherwise see my section on wiring harnesses)
- plug in amp to car / deep cycle battery by attaching negative to negative pole of car battery first. then attach positive or white/red/turquoise to positive. it should spark a bit, that is good. shows current is flowing. You should hear a hum or have your speaker burst into action. If not, look at the amp for a place where a fuse should be. fuses are like $1 at canadian tire. typical are 15, 25 and 30 amp fuses. they say what their rating is on the top. You can tell if they're blown cuz a thin wire inside will be all melted. look at one and you'll know what i mean.
Speaker Box:
there are many speakers at value village. what you need to find is one or a pair that match your amp. Say your amp is 4 ohm, house speakers are usally 8 ohm. this means that two eight ohm eighty watt speakers plugged into the same speaker terminal equals one 4 ohm 80 watt speaker worth of resistance. So you can use house speakers on a car amp, just make sure to try and match the resistance. If you dont they will still work, they will just be quieter. So for example you buy one mondo 18' speaker thats 8 ohms and plug it in, it will be quieter than it should. two of them with positives and negatives connected to the same terminals would pound.
so: look for speaker boxes with labels on the back saying their ratings. Look for 80 watts or more. some newer sony and panasonic speakers say theyre like 50-80w 6 ohm, but they lie. new speakers will almost universally suck. think playboy mansion 1970 style speakers. you want some bad muthas. Value sells single speakers cheaper, so a bad mutha will work fine.
To make your own sub box cheap: Take the box home and chop off the top so its a square. remove the crossover from inside (the wirey and circuty thing inside the speaker). You only need the big speaker, so saw off the top of the box above the big speaker and then cut away the extra box. glue and screw the very top portion back on to make a cube rather than a rectangle, ya dig. Lighter, more portable, and has a big speaker. Make sure to attach the wires going to the back of the speaker as + and -, and make sure to attach the cord well before reassembling the speaker box. ideally re-use the wire connection terminals the speaker came with and then its easy to plug in and unplug.
Speaker:
see above Or: go to a pawn shop and pick up a 10 or 12' 4 ohm sub speaker cheap, even more convenient if it comes in a box.
cost: $free - $50. dont buy a fancy one right away. get a cheap sub box and experiment.
NOTE: when buying speakers make sure to check the cones for damage. any rips or tears mean the speaker is no good. same with if the wire terminals on the back are damaged. this is very important to notice BEFORE you buy it.
Another thing to remember is that you should never plug a 4 ohm speaker into an 8 ohm amp or poof you're in for a surprise.
Battery:
Deep Cycle Batteries are what you need. they are made for this job. car batteries wont work as well and can explode. not to mention battery acid can spill. You want sealed deep cycle batteries.
NEVER TOUCH BOTH POLES OF THE BATTERY AT THE SAME TIME.
NEVER CONNECT + AND - BACKWARDS
Where do i get one?
Go to the back loading dock of marine electronics stores and look for them. Wheel chair stores and medical equipment stores have used ones. look around back or ask at the counter to buy a used one. say its for an art project. If you buy one from a store 2nd hand make sure they test it with a load testing volt meter. this will show the amount of current it is capable of holding. Any store that sells batteries will have a load testing volt meter. a regular volt meter wont show the true charge because the battery needs to be using current to work.
You want to look for Amp Hours (AH) and Current. My wheelchair battery is 33ah 13.3v (12v or near is fine). My full size battery is 90ah. Amp hours you can use math to figure out how long the battery lasts for but whatever 2nd hand batteries wont las that long anyways. you gotta try them to know. the more amp hours the longer it will run your rig.
cost: free - $50
note: you can use old car batteries just BE CAREFUL. get a battery box or at least put the battery behind a wall or something. remember the length of cord from the battery to your gear uses up power too.
car batteries can explode if current is drawn for prolonged periods of time, so watch out.
Inverter:
any cheap 400w or more inverter will convert 12v to household power. this will drain your battery faster than just running an amp. it lets you plug in gear tho, so its very convenient. If your inverter doesn't have a fuse, buy a cheap inline fuse holder for $5 from canadian tire. this way if you plug in the power backwards, you wont cook it (like i recently did.. whoops.)
putting it all together:
build some sort of case or attach it all to the speaker. attach speaker wires to amp, attach them to speaker. put input wires from mixer/ gear / cd player on input of amp. attach battery to amp (remember positive and negative, check twice.)
NEVER TOUCH BOTH POLES OF THE BATTERY AT THE SAME TIME.
NEVER CONNECT + AND - BACKWARDS
Have fun!
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