I live in an interior townhouse with very good sound suppression; however, a new neighbor has complained about the level I use to listen to my classical CD collection. Her constant complaining has reached the point where I had to resort to headphones in the evening - - or qui listening.
So, I acquired a new BHA-1, and installed it yesterday. More than satisfied! But, now I'll have to upgrade my current Sennheiser 660S cans to realize the maximum performance the BHA-1 can provide.
My bat-eared neighbor inadvertently caused me to rediscover the enjoyment of quality headphone listening.
Thanks, Bryston!