Piezos in a Line Array

[Mutley666]

Can piezo tweeters be effectivly used in a line array? Do they suffer from the same lobing effects as voice coil based drivers, or as they have no voice coil do they act more like ribbon tweeters?

I want to throw together a cheap and nasty line array as an experiment and don't really wanna cough up for expensive ribbons for an experiment!

[sreten]

Hi,

they will have less high frequency combing interference that plain drivers.
Due to them being more directional due to them being horns.

I don't see the connection between no voice coil and ribbons.

http://www.wle-shop.co.uk/modules/sh...odcode=902.475

is a cheap as it gets, (probably as nasty too !)

/sreten.

[Mutley666]

Thanks for the reply sreten.

I through that ribbons were not affected by lobing as they were driven uniformly (or near enough) over their whole surface, rather than from the central point as with voice coil drivers. Is the acutal reason purely because they are rectangular in shape and therefore have no centre?

If this is so, do this mean oval/rectangular voice coil speakers would behave in a similar way?

[pjanda1]

Have you seen Fitzmaurice's PA designs?

http://71.18.23.29/

(look at the DR series of PA tops)

I assume you might be asking about their credibility, but if not, here is an example of someone recommending it. Piezo line arrays have been discussed ad nauseum on his forum (a new doubter arrives every week or so). Everyone (I think) that has used them (granted, for PA) has agreed that they work very well in a line array. As piezos don't have a big magnet they should be easy to arrage, at the very least.

If you are uncomfortable with piezos you could try something like this:

http://www.partsexpress.com/pe/showd...number=269-708

Perhaps you can find something similarly cheap on your side of the pond. My understanding is that drivers response problems often are compensated for off axis (on axis peaks are often off axis dips and vice versa.) So cheap drivers work better in line arrays than by themselves. Arrays also compensate for problems with efficiency and dynamic range.

Either way (piezo or really cheap tweeter) the price is so low compared to multiple ribbons you may as well give it a shot.

good luck,

Paul

[sreten]

Originally posted by Mutley666
Thanks for the reply sreten.

I through that ribbons were not affected by lobing as they were driven uniformly (or near enough) over their whole surface, rather than from the central point as with voice coil drivers. Is the acutal reason purely because they are rectangular in shape and therefore have no centre?

Hi,

a piezo tweeter allthough having no voice coil is still driven from the
central point, no voice coil does not mean they are like ribbons.

/sreten.