No, T/S parameters are measured in free air.
If you are able to measure impedance, you could estimate DCR (dc resistance), and Le (voice coil inductance) by taking measurements in the box. Le is often measured at 1 kHz. You would also be able to determine Fb (vent tuning frequency).
You could also measure Lp (port length), Dp (port diameter), as well as Vb (internal air volume of the box).
With that information, you might be able to select a subwoofer that work reasonably well in that box, and with that vent tuning.
Of course, taking the good subwoofer out and testing for t/s would be preferred.
Hope this helps.
If you are able to measure impedance, you could estimate DCR (dc resistance), and Le (voice coil inductance) by taking measurements in the box. Le is often measured at 1 kHz. You would also be able to determine Fb (vent tuning frequency).
You could also measure Lp (port length), Dp (port diameter), as well as Vb (internal air volume of the box).
With that information, you might be able to select a subwoofer that work reasonably well in that box, and with that vent tuning.
Of course, taking the good subwoofer out and testing for t/s would be preferred.
Hope this helps.
I hv one blown driver JBL car subwoofer vebted box type.
I want to know it's thielsmall parameters to replace the driver.
I can get another working similar JBL for testing.
It is very difficult to remove driver.
Can i test thielsmall with the driver in the vented box?
If you are going to replace it you are going to have to remove it anyway.
Do you know the volume of the vented box, and can you seal it?
If so, you can infer all of the parameters. Damping material in the box will reduce accuracy. Measure the vented box impedance minima and maxima (Fl, Fb, and Fh. Measure Fc and Qtc in a sealed box. Do a search for the vented box compliance formula (Vas/Vb). You should be able to take it from there.
If so, you can infer all of the parameters. Damping material in the box will reduce accuracy. Measure the vented box impedance minima and maxima (Fl, Fb, and Fh. Measure Fc and Qtc in a sealed box. Do a search for the vented box compliance formula (Vas/Vb). You should be able to take it from there.
want to replace with some other matching speaker. so need to test thielsmall.If you are going to replace it you are going to have to remove it anyway.
To test ok box without removing speaker to get thielsmall of the driver.
Thanks Ron E for the details.
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