Looking for car amp

Brian this place has been there for over 20years they will use oem if you ask for it.....I use to have a sound company and had many JBL speakers redone there...might want to search your area but I know these guys are good

http://www.speakersaver.com/

[BrianG]

Originally Posted by bustitup

Brian this place has been there for over 20years they will use oem if you ask for it.....I use to have a sound company and had many JBL speakers redone there...might want to search your area but I know these guys are good

http://www.speakersaver.com/

I just called them and they need a speaker with a removeable back plate or magnet assembly. I told them what I had and he said probably not. He then said to "slide by" the shop and he can take a look anyway, but I said it might be a tad difficult since I'm in Iowa and he's in Florida.

I'll look around locally, but I did some searching when I moved here and there was no luck then. I figured I'd just hold onto it for now, but it seems that it needs to be retired. Would make a really nice fridge magnet. Poo.

Originally Posted by BrianG

I just called them and they need a speaker with a removeable back plate or magnet assembly. I told them what I had and he said probably not. He then said to "slide by" the shop and he can take a look anyway, but I said it might be a tad difficult since I'm in Iowa and he's in Florida.

I'll look around locally, but I did some searching when I moved here and there was no luck then. I figured I'd just hold onto it for now, but it seems that it needs to be retired. Would make a really nice fridge magnet. Poo.

yes you have to remove the backet to ne able to glue the flat surround of the voice coil after it gets perfectly centered...then you screw the basket back down and squeez it together...I used do a little voice coil and paper replacement myself when I was in a pinch...its not that hard..you just have to be carefull

what your baskets dont come off?

[BrianG]

I'm not sure. I'll have to take it out sometime and take a closer look. It looked like a one-piece cast basket to me...

Originally Posted by BrianG

I'm not sure. I'll have to take it out sometime and take a closer look. It looked like a one-piece cast basket to me...

if the speaker is no good cut the paper out and look for some screws holding the basket down........its got to come apart dude......its like saying you cant have your neu motor rewound because the can doesnt come apart..lol


if it went together at the factory it has to be able to come apart...I would bet....cut out the paper

order the parts and get the shims for the voice coils...its a pieces of cake

[BrianG]

lol, cut out what paper? The spider? I'll take a look tonight if I think of it (and have time). It's still usable for light duty so I'd rather not wreck it unless I KNOW it can be worked on...

[shizzon]

Car audio is on of my other expensive hobbies...I got more money in my car audio than i do rc at this point (about 5k). Gotta love it though, loud and crystal clear music is just something i love.

heres my setup: http://mobile.jlaudio.com/gallery/de...ehicle_id=2626

Ive always loved JL audio, there not cheap but you get what you pay for, Ive been running my sub on 1000 WRMS for two years and it still is in perfect shape. With this one sub and no sound deadening i hit 144.9 DB, and it is the cleanest sub that i have ever heard.

And the Focal mids/highs are very nice, i used to have some mb quarts but decided on these since mb quart was bought out by crunch.

[lincpimp]

The cone has to come off, IIRC. They are usually glued onto the spider and the surround is glued to the frame. They you can access the voice coil and the top of the magnet assy with the cone off...

I ran my 12" l7 subs in .5 cu/f boxes. They were the same size as the flange of the sub and about 10" deep. I angled the front of the box to cut down on standing waves. Very punchy that way, I listen to metal, rock, and tekno, so the subs have to be fast. The tube-like box worked very well, I actually blew the back of the proto-type out when breaking in the subs. Ran them at 3/4 volume for 4hrs straight during a mardi gras parade. Amp never even got warm.

I have a memhis 500d and a 200ab 4 channel to go in my truck. Bought a thunderform box and it came with 2 mtx 4500 10" subs. I will give them a try, the box was 300 bucks with the subs, or 299 without them... Not much room in a lightning, so I am not expecting the world.

[BrianG]

It hasn't been updated in a while, but this is/was my system:



That was in my Ford Contour, but when I got the Mazda3, I stepped down to a 2400 on mids/highs and put in Polk 5X7's. IIRC, I was gonna use the Diamonds in the front too, but crossover placement was an issue - those things are big! And I didn't want to cut up my car right away trying to get seperate wires for the tweeters and mids through the door jambs - it was hard enough getting ONE pair 16GA wire in there.

[shizzon]

Ive heard good things about the Hex's, haven't gotten to listen too them personally though.
Ive got a buddy who runs two of the type R 10's off 600 WRMS, it does pretty good. I just love the way a high excursion sub hits the lows!!! plus seeing the roof of my jeep flex a half inch is cool too, lol. Ive got some designs for a custom 6th order box from team toxic bass, but i haven't had the time or money to do anything with them.

[FG101C]

Originally Posted by kulangflow

Be aware of his feedback. He only has one feedback as a seller and it's negative. It's not to say that this transaction won't be good, but it's something to consider.

Did'nt even look at that, thanks for pointing that out. I'll spend that cash on some more rc stuff. That would be a sweet amp though.

[_paralyzed_]

Originally Posted by BrianG

I was working part-time at a local stereo shop repairing amps, :

crossfire told me $150 to fix my 1000d. Could you fix it for less? I'm sure you could use a side project

[BrianG]

lol, most of the amps I worked on were your typical class AB types. Usually, some kid tried to run 1 ohm load on a 4 ohm stable amp and blew an output transistor. Easy fix. Class D is a different animal since they are switching amps. I don't have an o-scope to troubleshoot those and is needed to measure the reference sawtooth wave and such. Personally, 150 is probably a good deal to make sure it's done right.

Ok, now I have my amp and all the parts taken out of the existing setup. I want to run at least a 1F cap, but the one I have is the typical round style and is too big (3" diameter) to put where I want. I look online and see they now have cap banks in a blingy package. Soooo, I figure I can do that! I'll "just" find a bunch of smaller 10,000uF/25v low-ESR caps, and put them all in parallel for the 1F value. Well, I could only find 2200uF 25v low-ESR caps but it would take 454 of them! Well, that's not gonna work. I'll probably pick up one of those blingy cap bank styles, and get rid of the casing (and stupid LEDs and voltmeter bling). But, I'd like to know where they get their caps? If I could just get the circuit sans case/bling, that'll save some cash.

[_paralyzed_]

those blingy cap banks are funny, but cheap. And large, 5 farads and up aren't uncommon now. On the cap note: is there any way to test a cap? I have two half farads in my van and only 600 wrms but my lights still dim would more capacitance help?

[BrianG]

Testing caps is pretty easy actually, and you can even verify the capacitance value.

1: Make sure it is totally discharged to 0v. Those large caps will still develop a charge if left alone for a little while, so once it is discharged, hook the leads together (short them) for about 10 minutes.

2: Hook a voltmeter across the cap.

3: Get a known resistor value. Something like 10 ohms @ 10w would work. Measure this with a meter to get an exact value.

4: Charge the cap through the resistor. Time how long it takes for the voltage to get to 63.2% of the supply.

5: Then, take this time (in seconds) and divide by the resistor value. This is the capacitance.

So, let's say it took 3 seconds for a cap to get to 9.1v on a 14.4v supply (63.2%) charging through a 10 ohm resistor. 3 seconds divided by 10 ohms is 0.3, which is 300,000uF.

The "rule of thumb" is to have 1F per 1000w of power. But, a cap will only help so much if the electrical system is weak. Headlights are around 100w each, the heater/blower motor pulls current, not to mention the computer, ignition, headunit, battery charging, etc. The electrical system has to supply all these devices PLUS your 600w system. And class AB amps are around 65% efficient, so the amp is actually requiring around 923w of power. At 14.4v, that's 64A.

Now, the dimming you're seeing is because lights get quite a bit brighter with just a little voltage. So, your alternator is supplying ~14.4v, but then when a bass note hits hard, that voltage drops to, say, 13v. 1.4v difference is pretty noticeable on lights. You probably notice the dimming less when the car is off because the static voltage is at the battery voltage (~13.8v) and batteries can handle pulse loads a little better.

Some people just add better/more batteries, but a battery is at ~13.8v. The alternator is still providing that extra ~0.6v, and if it is already loaded with stuff, the voltage will still dip. You can get an aftermarket high output alternator, but they can be costly. And most people don't realize that a stock alternator actually puts out more current at idle than a high output one. So, at a stoplight, you'll probably still dim.

In short, I wouldn't worry too much about the dimming. You aren't going to eliminate it since you'll always have voltage drop at high currents. But, if the dimming is very bad, it could be a sign of an overworked alternator...