Car Audio Speakers for PA application....

[Nails]

Hi guys...introduce myself...name is Paul from Perth WA.. first posting...doing a bit if DIY PA making at the moment using the olde Fane loudspeaker enclosure and design book..found some interesting cab types for which I,am having a look at putting together..the bass drivers are relatively easy to come by..but the burning question I have to ask is..is it possible to use high powered car speakers..lets say 6.5in...my plan is to put 8 x each into a cab..2 cabs in total just to run the mid range all through an electronic cross-over so only mid goes through them...
Any thoughts gents..Cheers

ATB

Paul

[Francec]

For all those who don't know, "Perth WA" is Perth, the capital of Western Australia.

FWIW, Paul, you may cop some flack for the Bose avatar.

I do think a fair bit more information may be requested first.

Frank

[Richard Ellis]

Welcome to the Forum Paul........
Using so-called High powered car-audio gear for PA work doesn't work well at all.
The key to PA work is high sensitivity drivers.....not "high power" drivers.
Check the sensitivity of 'Car' stuff......it is really low......it is stated as One Watt of input signal, measured at one Meter distant............or say 92Db@1W1M .........this is how it should be written. For 6.5" drivers you should be looking for 95+Db............Car stuff is way low at about 87Db....useless!

__________________________________________________ _Rick...........

[Nails]

Originally Posted by Francec

FWIW, Paul, you may cop some flack for the Bose avatar.

Frank

Thank you Frank for the heads up...my keyboard is fully loaded ready for the artillery of flack.......


Cheers Richard these one,s I,am considering are 91db...a little low from your recommendation....It looks like I,ll have to to some more scouting about and find something a little more suitable...Cheers

[planet10]

Originally Posted by Francec

Paul, you may cop some flack for the Bose avatar.

Frank, you gotta spell B#$% correctly. And Paul, they have sued for less

dave

[chris661]

The problem with low sensitivity is that you need more power to get it as loud as a decent PA driver at 1watt.

For example, take a 88dB@1w/1m car speaker, and a 98dB@1w PA driver. The car speaker will always need 10x the power to keep up (+10dB=x10 power), so if the PA driver is seeing 100w, the car speaker will see 1000w. This is a lot of heat, as the actual efficiency of any loudspeaker is very low, so the drivers would fail very quickly.
If you got 8 of the car speakers (3 doubles in radiating area), you get +9dB @1w. So you're looking at 97dB@1w/1m, and they're suddenly taking up a lot more room.
It's going to be very very difficult to beat something purpose-built at it's own game.

Chris

[Nails]

Originally Posted by Chris

The problem with low sensitivity is that you need more power to get it as loud as a decent PA driver at Watt.

For example, take a 88dB@1w/1m car speaker, and a 98dB@1w PA driver. The car speaker will always need X the power to keep up (+10dB=x10 power), so if the PA driver is seeing 100w, the car speaker will see 1000w. This is a lot of heat, as the actual efficiency of any loudspeaker is very low, so the drivers would fail very quickly.
If you got 8 of the car speakers (3 doubles in radiating area), you get +9dB @1w. So you're looking at 97dB@1w/1m, and they're suddenly taking up a lot more room.
It's going to be very very difficult to beat something purpose-built at it's own game.

Chris

Thanks Chris...that,s some sound information there[excuse the pun]..It,s looking like I,am going to reconsider my options...My original idea was to get away from the standard 2 x 12" mid-range set-up and try something a little different...Mmmmm...back to the drawing board maybe....

[nandababaji]

Hi Paul, I built something similar to your idea using cheap 50w Soundlab drivers and was very pleased with the result. I used six 6.5" in a smallish box together with a horn driver, crossover at 5khz. If you can find drivers of around 90-93dB sensitivity as I did, you will have a speaker 99-102dB efficient-enough to match any pro driver. My set up couple with two 18" subs sounded very clean, beating a 12" Fane pro driver and horn system (101 dB efficiency) I also built, sounding much smoother in the midrange. The smaller mid drivers can be used with smaller horns or bullets saving space AND money too because of higher crossover frequency. My mid drivers are foam suspension so are crossed over at 150hz to avoid excessive cone travel. You would have to avoid heavy coned plastic car drivers though-go for a light paper cone with a stiff suspension. Bose have sold millions...

[Nails]

Originally Posted by nandababaji

Hi Paul, I built something similar to your idea using cheap 50w Soundlab drivers and was very pleased with the result. I used six 6.5" in a smallish box together with a horn driver, crossover at 5khz. If you can find drivers of around 90-93dB sensitivity as I did, you will have a speaker 99-102dB efficient-enough to match any pro driver. My set up couple with two 18" subs sounded very clean, beating a 12" Fane pro driver and horn system (101 dB efficiency) I also built, sounding much smoother in the midrange. The smaller mid drivers can be used with smaller horns or bullets saving space AND money too because of higher crossover frequency. My mid drivers are foam suspension so are crossed over at 150hz to avoid excessive cone travel. You would have to avoid heavy coned plastic car drivers though-go for a light paper cone with a stiff suspension. Bose have sold millions...

Nice one Nanda....thats gave me a little confidence in my quest...so there is a possibilty...with the right type drivers it could come together..It,s all about the acoustics..... but thats what I,am trying to replicate that in car sound but on a bigger scale....crisp and clear especially in the mid-range section of the PA...

[Keriwena]

Originally Posted by chris661

If you got 8 of the car speakers (3 doubles in radiating area), you get +9dB @1w. So you're looking at 97dB@1w/1m....

Chris, mostly I agree with you, but you seem to be offering a free lunch here. If you apply 1 watt to a box with 8 speakers, how much power does each speaker get?


Nails, I've been looking for what you want for years, and I keep coming back to these:

Eminence Speaker | Speaker Detail