My favorite is the Grado but after I modded it. I popped it apart, punched holes in the drivers, added dampening to the magnet, and removed this plastic ring that is in there to help hold the screen in place but isn't needed. I also de-buttoned them. The sound is more open, bass a little deeper, separation is better. Soundstage, not much improvement but they are Grados. The sound with them is just so clear and powerful. I wouldn't say transparent or true, again, they are Grado and there is a known Grado sound. But these things are a joy. The G-cushes are a great upgrade. They make the headphones more comfy and they open them up a little bit. I think there is a slight increase in bass with them too.
A very close second is the Fischers. They are a bargin headphone that just does it all very solidly. Bass is nice and punchy and goes deep. Soundstage is decent, not the best, but certain acceptable. Separation is ok. The sound is just really, really nice and they are very comfortable and being closed, they really isolate well.
I really like the DT 770 Pro. They have great soundstage and separation was good. These are a bass head's delight. They need an amp for sure. All of them do really even though some will argue the Grados do not. Trust me, they do.
The AKG are my least favorite. They just lacked life. They have great soundstage and are extremely comfortable but they just didn't do anything for me. They are pretty flat and no bass.
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