Might be good to check cone excursion at the low end, if you tune a lot below Fs usually the Xmax will be the limit and the Faital is not exactly high-excursion driver.
In addition usually distortion levels increase significantly, are they audible is a different question.
Right, HR doesn't 'paint a pretty picture', requiring an 80 Hz/4th order hi-pass to give it just ~15 W down low, otherwise only ~3 W.
That means you can only get 3W before you reach the driver Xmax (maximum travel), the mechanical limit is more but even that will be reached with quite low power and after that you will get mechanical damage and destroy the driver.
hey this is incorrect just FYI. especially for pro audio drivers. XMAX is the linear region of the motor. past this point you get less force for the same input (this creates distortion) but there is no way you're gonna destroy the driver. its just not gonna sound that good
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Actually I checked, at the lowest frequencies the port loads the driver and the excursion is minimized. The port does all the work.
The highest amplitude is between 60-100Hz at only 2mm. At port tuning, it drops to 1mm. Below port tuning it doesn't shoot up crazily like hifi speakers because of the stiff suspension.
I was quite surprised that it could go that low of a port tuning of 40+ Hz with only a 6 db drop at 30+ Hz when Fs is at 80Hz, I was expecting a much bigger drop in frequency response.
I suspect that in spite of the stiff suspension of pro drivers, the back force from the BR cabinet holding the cone still much higher and the stiff suspension doesn't come into play as badly as I thought it would.
Oon
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On a slightly different note, if you have built a speaker based on the Faitalpro 8FE200, I am interested to hear from you.
Oon
Oon
Not really IME and it dates from '64, just depends on the available amp power, recording/playback level, recording dynamic headroom and whether or not there's some form of protection circuitry.
At 10.4 mm, for an 8" it does have a pretty long Xlim before bouncing off the back plate, though with excursion increasing 4x/octave..........
True and unless times have changed, 'linear' still represents 10% distortion, so doesn't mean it's a ~distortion free measurement as some assume.
What program? Regardless, it can below port tuning, so check with Hornresp or similar for greater accuracy.
With a 2pi [half space] mid-band ~93.92 dB/150 Hz, 40 Hz = ~ -7.2 dB, 30 Hz = ~ -15.92 dB, so meets your expectation. 🙁
GM
Hi GM,
The 8FE200 is a 8"pro driver and as such it has a compliance Cms 4× that of a typical hifi driver. Just in case somebody drops the mic, the cone doesn't do a one trip. So below the port tuning, it doesn't shoot up like normal drivers.
That's why it has such a high Fs. Being a pro driver, the motor structure is a bit different, it has a coil and gap about the same length. So it is fully immersed for the high efficiency. it has a field that slowly deteriorates rather than one that abruptly disappears.
Oon
I was thinking of putting it up against the wall and do it down firing. Us apartment dwellers don't have that 2 feet to stick it out from the wall ... so might not be so much of an issue with baffle step. But I might fit in the baffle step in the crossover after all. Will see...
The calculator is this one by Jeff Bagby.
Loudspeaker Design Software
But GM, I know you are an old hand and very experienced at this, if you want to do another simulation and propose me a new suggestion, I would be more than happy to hear it.
Oon