I am looking for an SPL Meter to calibrate my home theatre speakers. I went to ebay and found many types of meters, I found this one, would this be the right one for my use? http://cgi.ebay.ca/Radio-Shack-Analog-Sound-Pressure-Level-SPL-Meter_W0QQitemZ250174475607QQihZ015QQcategoryZ25423QQssPageNameZWDVWQQrdZ1QQcmdZViewItem Thanks