TOPIC:

Since I heard that changing internal gain from -12db to -18db improves the S/N ratio I opened the UMIK-1 mic and changed the gain from default -12db to -18db. However the OS still was showing -12db. I read comments that this was ok and internally it should measure -18db. Well, it did not. When I took the measurements of my mains today and checked the level with the REW's SPL meter it showed 97,8 db but when I used independently a Radio Shack SPL meter it showed 92 db. It was almost 6 db diffrence like between -12db and -18db. And yes, I changed the sensitivity line in the UMIK-1's calibration file from -7,230 db to -1.230 dB (the serial number is 700-1778).

So I changed the UMIK's gain from -18db to the default -12db. This time I looked closer and the SPL reading and noticed there was a diffrence of 1 db so I had to change the sensitivity parameter from original -7.230db to -6.230db to match the results in REW and Radio Shack SPL.

I did not calibrate the mic in REW as that option is not available. REW message says you do not need to calibrate UMIK-1 USB mic as there is already a sensitivity parameter included.