Dayton WT3P WT3 Bundled with Precision Scale

I am very disappointed about this tester.
This tester do not calibrated and do not working normally. I have 2 PC, Vista and XP,but this tester do not work with both PC. I am wrote to Parts Express for change, but got a strange e-mail:
"You may certainly ship it back to us for evaluation. before doing that though, I would
suggest contacting Dayton Audio directly to make sure we are not missing something. They have more resources in this area. I included a link to their contact page below or you can reach them by e mail at info@daytonaudio.com"
But I bought and paid to PE...

I received my WT3 in the mail the other day, along with the scale it came bundled with.

The WT3 setup and usage is a breeze. Install the software, plug in the USB, calibrate using the supplied resistor, and then you are ready to go.

It effectively measures a speaker's impedance curve and T/S parameters in about 5 seconds. I haven't used the Vas calculation yet as I haven't yet built a test box of known value.
I will eventually use this test equipment more extensively with my midbass enclosures in my car kickpanels while experimenting with aperiodic venting.

The scale is handy, though the on/off button is a bit tricky to turn "off"...I found that I need to quickly hit the button and release to get it to turn off...sometimes it requires a few tries.

I have previously measured subwoofers' T/S params manually and plan to purchase this tester after reading the reviews.

As a follow-up to Brandon from TX, especially with larger format woofers, the environment can greatly affect the measurements. I once measured an 18" Altec sub in two locations: 1) in a college dorm hallway, 2) outdoors, suspended from a tree. The difference in thigs like Fs was pretty substantial. I'd think it best to measure the woofer in a truly free-air environment, i.e. outdoors suspended in the air.