I have a SPL meter from RS and want to caliibrate my speaker levels. Im using the internal test-tones for now. here is my problem: I set the master volume on my reciver(kenwood 6050) to -15db which is 85 db right? So this is my reference level.now i set my SPL meter to 80 and put it on "slow" and "c". I am testing from the listening area. When i use the test tone with the reciver set at -15(85db) i have to have the fronts at +8db just to hit 75db on the meter. The rears are set at +7db each to hit 75db. the seperate speaker volumes on my reciver go from -10db to +10db. im at +8db just to hit 75db when my reciver volume is at -15db(85db). whats worng?