I mostly use Boxsim for my speaker calculations, but the other day I just wanted to look somethings up while at work, so I checked with an online calculator and my results was way off from what I expected. So when I got home I rechecked everything in Boxsim if I hade done any mistakes, but no. Checked with Basta! and it agreed with Boxsim.
So, why does online calculators say that I need ~250 litres to get a qtc of 0.5 in a sealed box? While Boxsim and Basta! says ~50 litres?
I calculated on an Wavecor WF223BD02.
I don't trust online calculators, but every single one I've checked says roughly the same thing, so now I need an explanation.
So, why does online calculators say that I need ~250 litres to get a qtc of 0.5 in a sealed box? While Boxsim and Basta! says ~50 litres?
I calculated on an Wavecor WF223BD02.
I don't trust online calculators, but every single one I've checked says roughly the same thing, so now I need an explanation.
Stuffing doesn't account for 250 litres vs 50. The difference isn't that big with no stuffing.
Boxsim 2.0 calculates 247.97 l for WF223BD02 with Vas=45.0 l, Qtc=0.50 and Qts=0.46. That's correct value with simplified basic formula Vb=Vas/(Qtc^2/Qts^2-1).
Actual could be something else depending on stuffing, box dimensions, leaks and other losses. More accurate formulas with estimation of stuffing and dimensions exist.
Typical reason for small differences is that programs calculate with different set of parameters, and all parameters given by manufacturers are not compatible with any combination of temperature and air density. But that's not so big deal and cannot cause 250->50.
Actual could be something else depending on stuffing, box dimensions, leaks and other losses. More accurate formulas with estimation of stuffing and dimensions exist.
Typical reason for small differences is that programs calculate with different set of parameters, and all parameters given by manufacturers are not compatible with any combination of temperature and air density. But that's not so big deal and cannot cause 250->50.
Last edited:
One approach without stuffing simulation is playing with Qa and Ql parameters. That is also quite much simplified and link to stuffing and internal dimensions in real life is weak.
For example Vb=57.4 l, Qa=1.3 and Ql=10 produces Qtc=0.5 and fc~43 Hz with VituixCAD.
For example Vb=57.4 l, Qa=1.3 and Ql=10 produces Qtc=0.5 and fc~43 Hz with VituixCAD.
Attachments
Last edited:
I think so but I wouldn't do very damped sealed unless target is to make resistive for current drive (without resistive transmission line or port).
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.