If the audio clips, and the meter doesn't "blow out", then in my opinion that is a defective meter.

ALSA already has an eq plugin (http://quitte.de/dsp/caps.html#Eq10) and I added this to it:

                if ((s > +0.99 && x[z1] > +0.99 && x[z2] > +0.99) ||
                    (s < -0.99 && x[z1] < -0.99 && x[z2] < -0.99) ) {
                        //clipped audio isn't exactly 1.
                        printf ("dsp/Eq.h:process(): input clipped :(\n");
                }

                if (
                    (r >= 1.0 || r <= -1.0) &&
                    (r < 20 && r > -20)) { //uninited memory?
                        printf ("dsp/Eq.h:process(): output clipped :( %0.16f\n", r);
                }