Bipole efficiency

[Jeb-D.]

What effect does a biplole setup have on efficiency, as opposed to a monopole?

 

[BWRX]

It increases it. It has been mentioned in many threads in this forum that the rear firing driver in a bipole effectively gets rid of the baffle diffraction step.

 

[Landroval]

How about the difference with bipole drivers wired in parallel and in series?

 

[Scottmoose]

Parallel add 3db. Series stays the same.

 

[ScottG]

Parallel add 3db. Series stays the same.

..depending on the output impeadance of the pairing amplifier..

 

[Scottmoose]

True. But you've got to have some approximates in this life... So I'm told anyway. (I never believed it either! )

Best
Scott

 

[Jeb-D.]

Thanks for the input. Do any of you guys have any good links to designing a bipole? I have 4; W4-1052's and was planning on making a pair of bipoles.

 

[Scottmoose]

Look at Dave's (planet10) two sites: www.t-linespeakers.org and www.planet10-hifi.com

Everything you will ever need, including numerous superb projects -Dave is the Bipole Master as far as I'm concerned.

Best
Scott

 

[Salas]

Parallel add 3db. Series stays the same.

dBW you mean, bcs in SPL things are different. Here we have corelated sound sources in close proximity. I have measured a +5 dB average up to 1.5 kHz. This means practically full BSC compensation. Good for listening away from walls. Best FR drivers for dipoles are the ones which exibit a naturally rising response.
See manufacturer's curve of single and then its bipole application here

 

[Salas]

*for dipoles = I wanted to type 'bipoles'

 

[rcdaniel]

Hi all

Would series connection of say 8 ohm drivers (to provide 16 ohm impedance) still not provide the 3dB gain if I changed from 8 ohm to 16 ohm output taps?

I will check out Dave's site as well.

Cheers, Raymond

 

[Salas]

It will stay where the single 8 Ohm driver is. Your cone travel is going to be half for each driver for same SPL as before. So you gain in THD. You are going to feel it more dynamic.

 

[rcdaniel]

That was fast! Thanx Salas.

Kind regards, Raymond