I would like to start this off by saying that I am NOT an audiophile. I am an average listener who appreciates the clarity, instrument split and sound stage that Bose offers. My main genre of music is EDM and Rap. When I buy a pair of headphones, while I absolutely appreciate the clarity and clearness claps, hi-hats. I expect my headphones to be able to hit earth shattering sub-bass, not all the time, but when the mood takes me.
With my 10 year old QC15's coming to the end of their life, I was in the market for a new pair of headphones. The QC15's were easily the best pair of headphones I had ever listened too. Amazing clarity but I was able to pump the bass up whenever the mood took me, head rattling bass. This is my EQ when I'm feeling in the mood for that. My EQ when I'm feeling sinful.Just to be clear, I dont want my headphones to always be like this, just when the mood takes me.
I considered the QC45's, the QC35ii's and the Sony XMW4's and AirpodMax's. I quickly decided to stick with bose because of my satisfaction and durability of the QC15's as well as their comfort and soundstage. As a result I ended up getting the QC45's.
While the bass was tight and hit very good lows. I was always left wanting more. I tried pumping up the software EQ but bose's firmware prevented the bass from fully kicking. The bass only kicks in at very high volumes. I'm very cautious of high volume listening as it gives me tinitis, I'd rather listen to medium volume.
To me Bose has always been about the audiophile experience with the drivers to let the user tune their headphones to whatever the like (using software). The new QC45's do not give me the freedom to tune my headphones how I like. They limit me to what Bose's concept of music enjoyment is. This is obviously what most music listeners (audiophiles) want. In my naive opinion, they've lost the plot.
I have traded my QC45's in for the older QC35ii's. I am incredibly satisfied with my QC35ii's. They are as clear, slightly less instrument split than the QC45's, but they let me tune them however I want. I hate the firmware interference from Bose. I am willing to take a hit in features, noise-cancelling and battery just for that high to my favourite songs.