Not sure why you boost 1.0K to 4K.
Do you like beef-up this range?
1k to 5kHz is the range the human ear is most sensitive.
The short answer is it sounds right to my ears. The long answer is, I want guitars to sound like guitars and have some edge to it particularly rock guitar. Also having been to live concerts in a good venue like our Auditorium, I want music to sound lively, sound bouncing off the walls, in this case headphones, to achieve that I have to boost the frequencies. And third having a mixer, I played around with it for 2 weeks before using. I discovered that boosting the mid-frequencies gives music its musicality, in fact its a very fine line to nail down. Music can still sound damn good when you don't nail these frequencies, but when you do, music has a bloom to it.
