12 inch woofer test, SB Audience
The 12" Mid-woofer
For now we have one 12" in this article:
- Sb Audience NERO 12mwn700d
We will also measure distortion with and without a 1.2mH air core inductor, to reduce the driver breakup impact on distortions when possible, as seen in speaker breakup article.
In essence: We use Back Electromotive Force principle with an air core inductor that will increase gradually the impedance (affecting the voice coil) and replace some EQ to linearize the woofer in the same time, it works very well if the woofer is already rising up in his final box.
It will reduce a lot H3 and H5 distortion related to breakup if there is.
Distortion measurements are done at 31.5cm 95dB SPL, all drivers are EQ flat to be compared : The SPL is the same on all the bandwidth, for all drivers, with and without air core inductor, the difference with and without air core inductor is not due to SPL but to Back Electromotive Force principle, as explained in our dedicated article.
SPL
Distortion Without inductor
H3
H5
Distortion with inductor
H3
H5
Time-domain measurement
As always, there’s nothing to see in the time domain if we stay away from breakup:
Conclusion
The driver has a well-damped breakup, so naturally there’s no rise in distortion. The increase in SPL makes it suitable for operation with an air-core inductor. We replaced some EQ with an air-core inductor effect.
The SPL remained the same, but we changed the impedance at breakup, so the driver performs even better in H3 and H5.
It’s a very good alternative to the 12LW1400.
The driver allow a crossover not limited by distortion, we can cut it when directivity match with an X-Shape X33 or X34 at 1150hz or even higher, without the need for an air core inductor.
