Well I worked more on my passive twin-t notch filter and have some results that worry me. I used the process @matt described to create the export then used REW to generate a 1khz tone at -1dbfs from the su-9. I had problems using the java drivers with REW and problems with 60hz but finally got that ironed out. I tested a D10s and D50s as well the results with the SU-9 are nit as good as Amir’s, but the D10s and D50s are.
I’m wondering if I’ve done something to makes the results look better than they should be with a simple passive twin-t and the QA402.