When I started listening to the Seahf LD-4.0 400 Ohm, I also noticed a smoothness which I never heard before. I wouldn´t wanna miss it now.
With the LD-4.0 400 Ohm the makers wanted a more balanced sound, and I guess that´s why in contrast to vapman´s review of the LD-3.0, I wouldn´t say that the LD-4.0 are "bass monsters". Take everything I say with a grain of salt, because I have yet 3 Seahf earbuds here I haven´t listened to (one of them being the LD-3.0 400 Ohm), but I think the LD-4.0 may be the best allrounder of all. Totally non-fatiguing, big soundstage, very analog sounding, deep reaching bass, but not as powerful and growling as the LD-3.0 320 Ohm.
This has even more bass than the LD-3.0 320 Ohm and better highs, but the sound lacks depth and width. It also sounds rather slow, so lacks PRAT which is where the LD-4.0 400 Ohm shine the most so far.
The sound of the LD-4.0 is much more balanced, it has a much wider soundstage, the flow is better, it has more dynamic headroom, scales better.
my SeaHf 400 ohms are very easily driven from any source - laptop or phone can do them great. They actually perform better on low power sources like this than the SeaHf 320
So where the 150 Ohm and 4.0 400 Ohm care more about the sound of the band as a whole(SIC!), the 320 Ohm present the music with more depth and detail. Very nice.
Just received my new Seahf LD-4.0 400Ohm buds. I´m listening right now. I´m speechless, totally speechless.
The 400 Ohm has enough dynamic headroom for any kind of music you throw at it. It even eats my Tschaikowsky 1812 Telarc album (with the original cannon shots) for lunch. But with the 150 Ohm it seems like every tune reaches my ears like it´s pumped up with steroids. The 400 Ohm present the music more with a kind of ease.
At least that´s my impression, and that´s why I think the 4.0 400 Ohm could climb to the top of the ranking list.
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