PA Drivers in Vehicles

[Pierre Le Sound]

Having seen the rip-off price of car sub-woofers, has anyone ever put a PA driver in a box, in a car or van?

I've got a JBL amp which puts out 220W RMS into 4 ohms bridged. I'm looking at building a sealed cabinet into my van ('coz i'm practical, Daz!:D )

Blue Arun sell a few likely units for much less than a car accessory shop.

[Dragonfly]

my friend did that i believe and was stopped on the a52 because his headlights were flashing to the beat :D :D :D

have no idea if thats actually true but its the story we all got.

[DMX Will]

It's possible, and end of the day, it's still a speaker :) Just match up the watts/ohms as you would normally!

Wouldn't advice you wiring up two cabs in your boot mind.... :P

[Pierre Le Sound]

I've just built a safety cage in the Transit, it's the idea time to build in the cabinet. AND, it's got a twin battery system in it, with split charging, from the previous owner.;)

[colint]

it's a bit more involved than just ohms/watts you need to think about the spec of the drive unit as well CIARE do drivers for cars as well as pro stuff look on here http://www.ciare.com/consumer_en/ they also have box designs on the site as well i've got a 1 x 15 (dual voice coil) rated at 500watts in a small pro cab for small gigs and it reall moves air and never let me down dispite being powered with a plx 3402 QSC amp
Colin

[pagan_flame]

Also you have to remember - in a vehicle amp you are outputting 12v, not 240v - if you look at some of the car '800w' speakers on the Sunday market stalls - if you put a 240v 800w amp into it then you would blow it straight out.

I have a 500w Sony amp in the van, going into a 2 x 10" full range box at the back - amp and speaker were both 20 quid each! All you have to do is hunt on Ebay for an advert in text speak with a photo taken with a mobile phone - and there's yer chav / Barry who is flogging last week's gear 'cos he is replacing it with more stuff on finance that he's seen in Max Power...

[sleah]

he's seen in Max Power...

..... who's idea of max power doesn't even register on everyone else's scale:D :D

2kw amp for yer Nova? yeah right! 2w more like :D

Anyway.... you can put bog standard speakers in the car/van/boat etc.
Car speakers are designed to more sensitive especially at low frequencies to be able to get more bass for a smaller speaker.
Like for like an 8" car speaker will pump lots more bass than it's PA equiv, which is designed for mid range rather than bass.
You'll also have to drive a standard PA speaker harder so the trade off is needing a bigger amp for the same volume.

You could use car speakers for giging, but because they are more sensitive, unless you drove them well below their full rating, they wouldn't last long.

[leighinstoke]

I know some guys go OTT with their car hifi so the tail of headlamps flashing isn't too far fetched - Andy, a mate of mine who I worked with years ago when I was at a garage, had 4 top of the range car amps in the boot of his Sierra (dressed-down Cosworth....though how you dress one down I don't know as they still look like a Cosworth due to the exhaust), parcel shelf full of drivers, sub woofers, tweeters everywhere, more drivers in the dash, Alpine controller with, I think, 3 multichangers. Must admit it did sound good and he actually played Acid jazz, etc, on it compared to some of the stuff I hear on car hifis.

Got to the point where he had to uprate the alternator and add a deep cycle leisure battery and split-charge system to power it all as the system was using more power and he had problems with the power supply to the engine, etc, when he had the sound system on at the same time as the heater, headlights, etc.

The last time I saw him, I think he had grown up, extended the family - and treated himself to a car with a Bose sound system in it. Old habits....etc...

Leigh....

[Pierre Le Sound]

I've done an experiment.....

220W RMS car amp into a borrowed 12" 150w RMS PA subwoofer, in it's origional cabinet.

YEEUCK!

The 240 volt versus 12 volt input must really make a huge difference, the cone sounded like a wet rag flapping in the breeze at any volume. :bang: :bang: :bang:

[axeman]

i worked in car audio installation in a previous life, and if the installed system is pulling enough power it can draw current away from other things (like lights) so you fit a power cap, which holds stored current until required keeping the electrical system balanced, ussually cheaper, easier and more practical than fitting an extra battery.

[sleah]

I've done an experiment.....

220W RMS car amp into a borrowed 12" 150w RMS PA subwoofer, in it's origional cabinet.

YEEUCK!

The 240 volt versus 12 volt input must really make a huge difference, the cone sounded like a wet rag flapping in the breeze at any volume. :bang: :bang: :bang:


To be honest I'm not even convinced that RMS means RMS in car speak:eek:
At the least a 100W RMS will be 2 x 50W RMS.... although yours may be mono.

Also the EQ will be different, I bet car amps are "pre" EQ'd for car speakers.

Did you try the cab with both the car amp and a real amp?
Maybe the cab was nasty anyway;)

The power supply shouldn't make any difference, providing there is enough of it, after all a PSU in a normal amp is trying it's best to produce nice flat DC........ but then at -v - 0v - +ve rather than converting from 0v - +ve like a car amp has to, which is probably why a car amp will never match a real amp.

[Pierre Le Sound]

To be honest I'm not even convinced that RMS means RMS in car speak:eek:
At the least a 100W RMS will be 2 x 50W RMS.... although yours may be mono.

Also the EQ will be different, I bet car amps are "pre" EQ'd for car speakers.

Did you try the cab with both the car amp and a real amp?
Maybe the cab was nasty anyway;)

The power supply shouldn't make any difference, providing there is enough of it, after all a PSU in a normal amp is trying it's best to produce nice flat DC........ but then at -v - 0v - +ve rather than converting from 0v - +ve like a car amp has to, which is probably why a car amp will never match a real amp.

The speaker was borrowed from a friend in a DJ shop, part of their hire stock, so i know it's ok.

Just bought JBL GT4-12 on E-bay for £16 plus £8 postage. That's the recommended pairing with the amp, Max RMS 240W.

Stangely enough, the photo looked like it had been taken with a mobile phone!

Thanks for all the input.

[pagan_flame]

Just bought JBL GT4-12 on E-bay for £16 plus £8 postage. That's the recommended pairing with the amp, Max RMS 240W.

Strangely enough, the photo looked like it had been taken with a mobile phone!See, I don't just make this **** up y'know... :D :D :D :beer1:

[Corabar Steve]

Language Malcolm! :d

[sleah]

See, I don't just make this **** up y'know... :D :D :D :beer1:

Sounds like a voice of experience;) Wasn't your amp he bought was it:lol: