Forum Post: VU meter with PCM3070

I'm trying to implement a VU meter with a specAna component in my PPS. I use a 1kHz sinewave input signal that I step in 1dB increments. I peek, with the memory tool,the specAna output DSP_D_coef =90, M7 and get an output difference/step of anywhere from 0 to 1.5 dB. Is this typical? What resolution can I expect? My PPS is a linear system with no compression/expansion. I also use a low pass (100 Hz) and high pass (10kHz) biquad before the specAna component. 

DATA:           5 dBr , M7= -42.25      6 dBr, M7= -40.75    7 dBr, M7= -40.75    8 dBr, M7=  -39.5    9 dBr, M7= -38.25    10 dBr, M7= -37.25,

Thanks,

Tom