Unable to measure T/S parameters

[wonderfulaudio]

Hi,

I am able to measure the subwoofer's impedance but I am unable to measure T/S parameters, can somebody please help?

I get very low value of Qes and hence very low Qts.

Thanks and Regards,
WA

 

[stv]

something seems to be wrong.
the impedance should be lower and get near Re at low frequencies.
is the subwoofer mounted firmly when doing measurements?
you could also tick the checkbox "estimate DC resistance".
anyhow your measurement setup should be optimized.
for first rough measurements i sometimes press the woofer with it's magnet towards a heavy table.
do not move the speaker basket or let it move/vibrate during measurements!

 

[bucks bunny]

Looks like there is some coupling cap in series with LS

 

[head_unit]

the impedance should be lower and get near Re at low frequencies.

Yes all of what @stv said, presuming there's no coupling capacitor. You have a box leak or gasket seal is not tight. It is one of the ways I used to check if I had a tight seal-I'd set MLSSA to some insane number of points so it would "measure" down to 0.0000001 Hz or something crazy.

 

[ctrlx]

did you check your setup by measuring some resistors like 5 ohm and 47 ohm ?

are you using a power amp as a buffer between the soundcard and speaker ?

 

[wonderfulaudio]

I havnt measured a known resistor yet. Now that you say, I will do it. I dont have any power amplifier connected. I am using Behringer UCA222 that has headphone output and its that I am using

 

[bolserst]

Unfortunately, the UCA222 likely suffers from the same low frequency crosstalk between inputs and outputs that the UCA202 does.
This makes taking accurate woofer impedance measurements impossible.

Perhaps the fix posted for the UCA202 can be implimented on the UCA222.
Behringer-uca202-fixing-the-low-frequency-cross-talk