[PurpleCow]

So I have a pair of brand new HD598, I was thinking of selling them to get the HE-400, are the differences between the phones worth the extra $150+ price for the HE-400?

 

[MattTCG]

You're comparing two very different hp's here. So it really depends on what you're after. When I owned the hd598, I remember it as mid centric and lacking in mid and sub bass. It was very light, comfortable and nice looking. Also easy to drive. I just couldn't get over the bass light issue despite the nice mids and treble. 
 
The he400 will deliver the bass in both weight and texture. It's a much heavier hp and not nearly as comfortable as the hd598. It's slightly harder to drive but still has very reasonable amping requirements. There is a slight treble spike in the 10 hz range. Some will like it as it adds a touch of sparkle to a hp that is known to have a dark signature. 
 
IMO I'd say that the he400 is worth the money and a worthy upgrade.
 
gL!!

 

[fabio-fi]

The HE-400 is a step up in terms of sound quality over the HD598. Each of them are more suited for certain music genres, depending on what you like. 
 
If you are prepared to buy a decent amp, then go for them. 

 

[PurpleCow]

So if I go with the he-400 ill have to get a decent amp/dac?

 

[mingamo]

Some people prefer the 598 to the 600 which is often compared to the HE-400.
People like the 600 for its effortless natural and neutral sound that just "works".
 
Dont take my word, but the senn HD 558, to me, sounded exceptional, and it seems to have slightly more bass compared to the 598 when modded and might save you a few $. They use the same driver.
 
Maybe look at the HD 650 or HD600 as an alternative to the 400 aswell; they are also really comfortable.

 

[Gnomeplay]

Quote:

So if I go with the he-400 ill have to get a decent amp/dac?

Not necessarily, the HE-400 are extremely sufficient for being planar headphones. You could shop in the lower end Fiio E17 range and it would drive them perfectly fine. A lot of people drive them with something in the caliber of the Schiit Magni + Modi stack. There will always be room for improvement, if you you decide to pull more out of them later on with better amplification you can let that be a side goal.
 
My *personal* vote is for the HE-400. I haven't personally listened to them myself but I prefer the ortho sound over any dynamic headphone I've listened to thus far. That's not to say that you won't be completely the other way around though.

 

[PurpleCow]

I guess I'm just trying to justify the price difference for what I'm going to be using it for. I listen to alot of different genres except for prob metal lol. I prob won't be using a lot either but I just wanted a good decent headphone.