I
I have owned pro4aa headphones seems like forever,the first pair I purchased in 1976 so they are well broken in by now.
the second pair in the early 80's ,both are working great and sound incredible, I prefer the pro4aa over the pro4aaa,s they just sound better to me.
the bass is deep and well controlled,the midrange is for me perfect and the highs are clean and bright. And noise isolation is great.
Like many have said yes they are a bit on the heavy side, but after a bit, when I am fully immersed in the music I do not notice the weight.
now for the tightness just bend the headband out a bit,not to much and no the bass is not reduced.
Like others have said these are not exercise headphones,they were designed for heavy use in studios where they are dropped,kicked and
thrown and made to survive for years and they do. And Koss does have their life time warranty which I have used,All they require is $9.00
for return shipping.
If you need lighter headphones look at their website for other models.
By the way I don't work for Koss in any way

And Koss has the lifetime warranty, try and find that with another headphone company!
I
I have owned pro4aa headphones seems like forever,the first pair I purchased in 1976 so they are well broken in by now. the second pair in the early 80's ,both are working great and sound incredible, I prefer the pro4aa over the pro4aaa,s they just sound better to me. the bass is deep and well controlled,the midrange is for me perfect and the highs are clean and bright. And noise isolation is great. Like many have said yes they are a bit on the heavy side, but after a bit, when I am fully immersed in the music I do not notice the weight. now for the tightness just bend the headband out a bit,not to much and no the bass is not reduced. Like others have said these are not exercise headphones,they were designed for heavy use in studios where they are dropped,kicked and
thrown and made to survive for years and they do. And Koss does have their life time warranty which I have used,All they require is $9. 00
for return shipping. If you need lighter headphones look at their website for other models. By the way I don't work for Koss in any way

And Koss has the lifetime warranty, try and find that with another headphone company!