View Full Version : What do these speaker terms mean?

PV Audio
09-19-2006, 10:14 PM

Like, I know what they MEAN (aka Fb is tuning freq, bl is motor strength and z is nominal ohmage (impedance)), but what do the terms stand for and where do they come from? Thanks


PV Audio
09-19-2006, 10:44 PM
Come on, someone has to know!

09-19-2006, 11:02 PM
Physics and circuits. F is for the frequency of the box based on the resonant frequency of the air in the port. I'm pretty sure that one is close.

B in BL is for the flux density in the gap. The L is for the length of the coil. When you multiply them, you get BL.

Z is just a variable in physics that's used in circuits to show the average impedance since impedance will vary with frequency.

PV Audio
09-19-2006, 11:04 PM
Sweet, the only one of them that was actually confusing the **** outta me was Bl. I figured Fb was Frequency of Box, or something, and that Z is just a term. But Bl didn't make any sense. Grazie!

09-20-2006, 10:50 AM
We type a lot of them as Fb and Qms and so forth, but the proper annotation for them is everthing after the first letter should be a subscript. F is frequency. The subscript just specifies which frequency is being discussed (i.e. S is speaker resonance, b is enclosure resonance, 3 is 3dB down freq, etc.). They are all pretty much derived from plain English except Z which is the symbol used for impedance, as mentioned above.