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Mazda_Brian
26-08-2004, 06:30 PM
Hi Guys,

I have my audio setup, not much, but 2 grand says it sounds nice, it's clear, and I enjoy it.

I have a serious issue with it though, my car doesn't quite have enough power to keep the system thumpin, what's the best way to provide more power?

I have thought about Paralleling more batteries (bigger batteries) into the system, but then this brings the problem of wieght, I am currently getting a new alternator installed, but I cant eve get 30 seconds of clear bass without the power being killed so much it cut's the amp.

B.

platypus
26-08-2004, 06:36 PM
pop caps? and a larger alternator

lamby1986
26-08-2004, 08:20 PM
im novice at this but, you sure its not the amp that is the problem?
[i'll only need one person to say you have no idea if thats the case]

chipa
26-08-2004, 08:37 PM
cannot beat the 1 farad caps! :) of course there could be another problem... What actually happens after that 30 seconds?

Mazda_Brian
26-08-2004, 08:43 PM
The AMP is fine in other cars, but does have a heating problem (the entire setup will be updated shortly, incorporating 2 subs, probably an extra battery, and custom made box.

I dont see the need for a Farad Cap, the amp is only pushing 220wRMS, and the woofer is a small 10", but it's 550wRMS.

Maybe a 1/2 Farad Cap would be alright, but still shouldn't be required on a small-time setup like mine.

B.

CityEnd
26-08-2004, 08:46 PM
tell us what system you have and what setup u've got, that will help us help u :)

platypus
26-08-2004, 09:02 PM
sounds like you ain't got a problem with the setup then if thats its power.... i'd take a wild guess and say somethings wrong

2nd wild guess is that your earth is bad, you might want to make a new one or scrape the paint back better on your current one.. what gauge wire you running for power???

chipa
26-08-2004, 09:27 PM
In pure electrical terms a large cap is not nessesary, but It certainly helps your system in several ways. Like the fact the your battery/alternator are not designed to constantly provide large current peaks.

Anyways as ahb11m says it does sound like you have a problem with your power delivery somewhere.

Zed
26-08-2004, 10:12 PM
The power rating of a sub has nothing to do with the drain on your car's electrical system. And you're right, 220W RMS is a small set up that you shouldnt have any problems with.

I'd be looking at checking the amp's wiring and especially ground lead. What gauge power and ground wires are you using? Where is the amp grounded? Is the sub providing too low an impedance for the amp to cope with? Where is the amp mounted - is there sufficient air space around it for cooling? Is the amp shutting off because its overheating? Do your lights dim at night to the beat of the sub?

Before you go adding extra batteries or caps, I'd be looking at making sure all the components are installed and set up properly, coz with only 220W RMS, your stock electrical system should cope with that no probs.

Dogo
26-08-2004, 10:19 PM
i'd forget about a cap - the alternator should make a good difference, and the money would be better spent on a battery than a cap. an optima or oddyssey would be a good choice, but even a heavy duty Century should power that setup no problems at all.

it could also be some dodgy wiring somewhere. grounding directly to the battery can cause it to 'hog' the power too, so make sure u ground to chassis

Mazda_Brian
27-08-2004, 07:08 AM
The wire is pretty thick (not sure what gauge as it came from Disk Smith a couple years ago, and was spare).

Currently, the Amp is located on the rear seat, there is air flow, although after a long (6 hour) hammering, the amp is extremely hot to touch and does start shutting down due to heat.

I am currently in the planning stages of a completely new installation in the boot, after seeing some of the "nicer" systems on last Sunday's Blue Mountains cruise, I was thinking of the 2nd battery for lights, re-designing the box (which keeps moving around at the moment anyway), and completely moving the current setup to "show it off" a little more.

I have the box planned out, including addition of a 2nd sub (same 10" as the current), but with the current issue, I dont want to go adding more pressure to the system.

The system is a Pioneer DEH 5550, 6.5 inch 150wattRMS splits in the front, 6.5inch 180watt 3 ways in the rear, an MTX 202 Amp, and Pioneer 10" "free-air" woofer in an inclosed box. (although it's a free-air, it still sounds **** mounted on a hatch parcel tray, the boot doesnt seal enough to give it justice).

I was looking at an upgrade to about 500watt RMS Mono Amp, and putting the 2 Pioneer's (2 new pioneer free-air subs, and selling/dontating the current) into series and running them off 1 channel, I could also parallel them, but I need to make sure the AMP is 2 ohm stable if I do that.

Currently, the entire system (except the amp) is pioneer, I did this because I like Pioneer and because I could :)

I am thinking a complete re-installation of the Amp is definately in order, I might get some decent wire tomorrow, and move the amp to a resting area in the boot until I find a perminant home for it with my new setup on the way. If the problem is fixed with a new grounding position (currently grounding in the spare wheel well), then I will proceed to Bunnings to get my MDF and start building my box.

BTW guys, I want to have a perspex front (or clear front), I have heard that you would need about 2" thick stuff to keep the rigidity of the box, is this right, and what would some of you audio show-sters suggest in the way of "jazzing up" this fairly ordinary setup. (Keeping in mind boot space is no problem, but I will need to get to the spare wheel at some point in life).

B.

platypus
27-08-2004, 07:21 AM
it wouldn't be 2inches, but i'm sure the perspex would need to be thick, like 25-35mm

in terms of rigidity you should use glass really, but you need to make sure its all mounted correctly... and not too tight

perspex is a soft material, hence it doesn't shatter with high impact, so you would want something thicker to come close to MDF

Mazda_Brian
27-08-2004, 08:02 AM
hehe, last time I tried a box like this I used glass, I also used rubber to seal the edges, but after opening up with 2 15" Monsters, I spent the next 3 weeks vaccuming glass fromt he boot, not again :)

I want to get Perspex or something simlar, I also want to mount some lights inside the box, so that the lighting froms from inside the box, and reflects to inside the boot (might even look at hooking the lights to my boot-lamp, and having an on-off switch. (this is all still in the planning stages).

I want something that looks and performance nice, but dont want to go spending thousands on it (just yet).

B.

platypus
28-08-2004, 08:48 AM
your box was clamped too tight... thats the only way to break shatter proof glass in that kind of setup - the thickness should be app. 1 inch (25mm)

Gavsta
28-08-2004, 12:36 PM
For looks get your Perspex/Glass laser etched with a logo (Pioneer?).

Then mount LEDs around the inside of the box next to the glass so the logo becomes illuminated.

platypus
28-08-2004, 12:42 PM
robbos setup is pretty good, you should really look at that one
*edit*
there is lights in this pane glass setup, so when darker, or at night the leds actually light up the pane... looks good
pinched!!!
http://www.astinagt.com/readers/~ROB-80E/DCP_2245.jpg
http://www.astinagt.com/readers/~ROB-80E/DCP_2244.jpg

ezin
29-08-2004, 06:35 PM
U said the amp pushes out 220wrms, and the woofer is rated at 550wrms, U've answered ur own question. One rule of thumb is that the amp must have more power output than the rating of the speaker or it will cause the amp to keep cutting out. Even if its cold in the morning and the amp has not even heated up, it will still cut out due to the fact there is to much current going through the cicuitry inside the amp. U could allways hook up a more powerfull amp and see how u go. good luck with it.

Zed
29-08-2004, 11:00 PM
ezin, a speaker's power rating has no effect on how much current an amp will draw. The power rating is a measure of its mechanical/thermal power handling, not how much power it will "suck" from an amp.

Mazda_Brian
30-08-2004, 10:03 AM
Zed is right, I had smaller, larger, and it still has the same problem.

I have a feeling it's the "goof" that hooked up the Amp for me...

I had a look at the wireing, not sure what guage it is, but it's thin, so I thought this was the issue, called the knob up to have a blast at him, told him "THICK ****!!"

He then tells me "there is 3 runs of the thin stuff, because he ran out of thicker guage".

I didn't have time this weekend to do much more than have a look at the wiring, and it's "disgraceful" to say the least. I will be re-installing the AMP in a new "cooler" spot this coming weekend, and using proper guage wire, and creating a new grounding as well.

B.

JynX
30-08-2004, 10:28 AM
Depending on the length of the run I would probably use 8 gauge for that sort of amplifier.

If thinking about running another amp, I would prob run 4 gauge from the chassis to a distrubition block then run 8 gauge to each amplifier keep the runs relatively short.

Then again if you want wow factor, get some 0 gauge :)

I probably wouldnt worry about caps untill you have exhausted the larger capacity batteries.

When I had my system in full swing I would only notice a power drop when I was stationary and had the system cranked pumping some low bass. Driving there was never a problem.

KittyKatSmack
31-08-2004, 04:07 PM
Ah yes, JynX's stereo is famous!!!

:lol:

It was so you didn't have to listen to his old exhaust.....

:P



*bolts*

Critter
01-09-2004, 06:07 PM
Sounds to me like the amp is seeing a load which is lower than it likes.

Is the sub a dual 4 ohm wired parallel to 2 ohms and the amp if bridged to a 2 ohm load WILL get hot and draw undue current, turning power from the charging system into heat.

I am running 1kw of power amps with stock charging system, stock battery etc. with only the occasional light dimming at night and I DO crank the system.

Cabling tho is THICK 0 gauge and the earths are very short, which is crucial.
Also the earth from the battery is upgraded and short.

With the sort of power you are running if the system is done properly you should have no power drain issues.

And yeah, 25mm perspex is plenty thick if installed correctly.

Mazda_Brian
13-09-2004, 07:47 AM
Got the problem sorted (finally).

Well it's only a temporary fix at this stage, but the ******** that installed the amp earthed at the battery.

I have since earthed at the Chassis straight under the back seat, the run is all of about 20cm from the amp to the earth point, the amp yhas NOT cut out since, even when the engine is off, whereas before it would cut out within 20 seconds of killing the engine, sometimes it was common to have 3 beats and then dead amp.

I am still getting a fair bit of noise coming through, but I think this is from the head unit, and it's all still on standard wiring, this will be upgraded to a complete new run of cables and a basically re-install and run the cabling from the headunit.

B.

Zed
13-09-2004, 08:11 AM
Good stuff! Glad to hear you've sorted one problem out at least. :)

Mazda_Brian
13-09-2004, 09:44 AM
Yep, got the first issue sorted.

The 2nd issue I have is that I get the CD Motor and Head motor's interupt noise through the sub when I use a CD (crystal clear with radio).

I am wondering if I have an issue with grounding on the head unit, as it's all using the standard cabling that's now sum 10 yrs old.

I will re-wire this on the weekend when I have nothing better to do, and test again.

B.

shock
13-09-2004, 09:59 AM
also check that the rca cabling isn't bent in weird places or the wire isn't rubbing against the body or something behind the headunit...

should get rid of most of the problems there...