3dB is partially correct. But actually you need to double your power just to get an increase of 3dB. "Twice as loud" is a 10dB increase. At 35watt difference is most likely not audible. Your maybe getting 1dB higher max volume which is pretty much the smallest noticable difference in volume.
Most likely, the difference in quality is due to the better DACs & use of higher quality parts.
The electronics end of a system contributes the least to the actual sound. In fact a receiver shouldnt change the sound at all if its good. A lesser tier avr can color the sound & add or subtract from the original material. So your older Yammie was probably slightly degrading the sound & your new Yammie is cleaner/clearer.
Most people think that upgrading a receiver should improve their speakers in a noticable way when in fact the improvements are typically very minimal if at all. Its the feature set & quality of components that increases the price & model. Sound quality improvement?...yes but not much!
Your RX-A3000 is a great receiver!!! You've made a great choice. It will last you a long time & is very "future proof". So make sure its all setup correctly, that you tap into all its features & enjoy your upgrade. Next time you have extra $ upgrade your sub or speakers. Those can give you a huge improvement in actual audio quality!!!
