Dual Cone drivers and Line Arrays

[fr0st]

Hi all
I've been doing a bit of reading about line arrays and the efficiency gain of using multiple smaller speakers over single drivers.
As I understand it, to get the sensitivity of any number of speakers whilst keeping the total current constant is 10*log(# of speakers) + sensitivity of one driver.
After having another browse through my local electronics shop catalog I found these drivers .
Using 4 of these drivers per speaker it would make a really simple (theoretical) 101dB/1W/1m speaker.
Apart from my intended application of surround speakers, I also thought of thier advantage as a car speaker.
Line arrays are surpose to give the best near field response and you can't really get any closer to a speaker than in a car. And off a ~25W rms headunit, I could obtain a theoretical 115 dB with some headroom. Is there any problem have the array laying horizontal but still pointed at the listener and in the fairly small car enviroment?

Although there isn't alot of info on the speaker, what are the chances that the 95dB sensitivity doesn't cover the entire audio band?
Would I be better to ditch the dual cone for a standard speaker with less efficiency? (link to alternate speaker

Keep in mind that in either system a sub will be used for low frequency's. Tweeters will also be used, I'll think about them later though

Thanks for all your help
Matt

[Bill Fitzpatrick]

Gee, that alternate speaker looks just like the other one.

[fr0st]

Sorry about that.
Here's the proper link
http://www.altronics.com.au/index.as...=item&id=C0635

[johninCR]

I don't think you want to put an array in your car due to their limiting effect on dispersion. With arrays the term "nearfield" has special meaning.

[planet10]

The 1st speaker is noted as having a strong midrange presence... by the time you knock down the midrange hump, they aren't going to be 95 dB....

The 2nd driver looks an aweful lot like the Radio Shack 40-1197 (aka budget FE103)... i'd be very interested in finding out mor about that one.

dave

[Tim Moorman]

The first unit with whizzer has a 125 Hz resonance, probably needs 300 Hz to get to near midband efficiency, so your sub would need to span up that high, or you will have weak midbass/loud mid balance problems.

The second unit looks much better, lower resonance freq, loses the whizzer, still wide bandwidth. Sub up to 200 Hz?

Horizontal arrays will comb filter badly causing uneven response due to cancellations. Not usually a good idea.

A pair stacked vertically would be really high output in a car - at least 95 dB, possibly more if your amp works better into the resultant 4 ohm load. 20 watts will provide enough output to run the occupants out. Just don't know how durable they might be.

Tim

[Brett]

Originally posted by planet10
The 2nd driver looks an aweful lot like the Radio Shack 40-1197 (aka budget FE103)... i'd be very interested in finding out mor about that one.

Looks (and specs out) a lot like the Foster drivers we used in the line arrays we built in the early eighties.

I have an Altronics account, so I might buy a couple to try.

[fr0st]

Thanks for your surgestions.
Will any sort of multiple speaker arrangement work in a car well?

As for surround speakers, using four of the single cone drivers would be my best option?
I'm fairly sure that surround speakers have very little content under 300Hz anyway. It may be wise to experiement on that one though.

I have an Altronics account, so I might buy a couple to try.

If your in Perth let me know
I work for a store that stocks some altronics gear so I can order a whole heap in if you want a large(ish) quantity or arange a group buy if need be.
They also have a new 97dB neodymium PA sub which looks quite tempting.

Thanks again
Matt