Help needed for a new beee!

[ciccio54]

Hi all. As per title i am new to the forum and this is my first post so be patient ...
I have been using REW in is basic function to check the performance of my DYI speaker and all is fine there
but i want to build e sub with a speaker i have in house but i do not know the T&S parameters for it
No problem, right? So, i build my Jig for impedance measurement as per pictures and i try to calibrate and i measure the open circuit and seems to work see picture? than i measure the short circuit and i get this message please see pictures.
I check the jig and i cannot find the mistake if any. I swap the channel nothing changes so i am stuck.
The measurement system is composed by a laptop an audio card beringher UAC202 my famous Jig and..that's it
i use the headphone out on the audio (but i tried with line out same result) card as source and the reference resistor used is 120 Homs (this what I had...)
Any help would be appreciated...i just cannot move forward. Please

 

[ciccio54]

Hi guys
Anyone?
I understand that my problem cannot be so interesting for more advance users
But I can really use some help here
Thanks in advance -)

 

[John Mulcahy]

When you measure the short circuit the measurement input gets connected to ground, but both inputs have the same input level of -14 dBFS, so that cannot be correct. Make sure the UCA202 default format on the Advanced tab of the Windows audio Recording properties is not mono and the UCA202 monitoring switch is off.

 

[ciccio54]

When you measure the short circuit the measurement input gets connected to ground, but both inputs have the same input level of -14 dBFS, so that cannot be correct. Make sure the UCA202 default format on the Advanced tab of the Windows audio Recording properties is not mono and the UCA202 monitoring switch is off.

Thanks John
I checked and it was set to one channel 16bit. I set it now on two channels same bit and it now let me finish the calibration process. However now during the open loop calibration I get a warning that a timing offset of one sample was detected. It says that shall be compensated but is unusual. why is that?
Thank you again John
It is my understand that you are the Rew author. Great job what a piece of software you created.

 

[John Mulcahy]

Some ADCs interleave their sampling so you end up with a channel offset. Quite rare nowadays.

 

[ciccio54]

Some ADCs interleave their sampling so you end up with a channel offset. Quite rare nowadays.

Nothing to worry so
Good
Next step is try to get the T&s parameters for my woofer
Thank you John for your help
Apreciate.