I can't figure these strings out, but seems as ever since I put these strings on, I've had to turn my amp up to reach the same output volume I had when I was using slinkies on the same bass. Does the black coating kill the "amplification" of the strings? They are brighter tone, but the volume/output seems lower. I have to turn the volume up say about 2 ticks on a 10 tick volume knob to bring it back to where it was before putting the Black Beauties on. Has anyone else experienced this? This is really puzzling me. Thanks.