T-S parameters and efficiency( 2PIor 4PI)

[Henckel]

Using a set of T-S parameters it is possible to derive the effciency of the speaker. Specifically i am working on Peerless HDS 134 832873 which according to the datasheet has an efficiency of 88,3 dB/2.83 V - this is confirmed by LSPcad and unibox as well based on the basic T-S parameters.

Now this efficiency is that in 2pi or 4pi ? ( aka with or with out baffelstep ) ?

The Thympany datasheet referes to IEC 60268-5 as the measurement specification.

Thanks for any help

Morten

[AndrewT]

Hi,
since the manufacturer has avoided making it clear, then it's probably 2Pi space.
Similarly, since they are quoting /2.8V, I suspect this is a 4ohm driver.
If they have used both tricks to their advantage then the quoted sensitivity could be 6db more than some others that play fair and state clearly how they are using the parameters.

[Saturnus]

To be totally fair, very few manufacturers use free-field (4pi) measurements. And they would certainly specify it if they did.

[Svante]

Hmm, I thought i posted here yesterday...

Yes, sensitivity is typically given at 2.83 volts and half space (2 pi).

[sreten]

Originally posted by Henckel


Now this efficiency is that in 2pi or 4pi ? ( aka with or with out baffelstep ) ?

Morten

Hi,

It is without baffle step. so a 2 way with BS would be around 83-84dB/2.83V.

/sreten.