[tehsprayer]

I can currently get a pair of HE-400i for $395 USD and the HD650 for $500 CAD (often goes on sale for $350 USD) though. 
 
Consider both headphones priced at the same value, what one would you get?

 

[retskrad]

hd650. the only reason you would get the 400i is because it has better bass.

 

[Rhamnetin]

What source will you be using these headphones with?  Do you have an amplifier?  What sound qualities do you want in a headphone?  The HD 650 is very warm, relaxed, and somewhat dark (somewhat subdued treble and tilted downwards), while the HE-400i should be more linear/neutral and forward in the midrange though personally I never heard it.  I'd get the HE-400i because it probably plays into my taste more, and because I prefer its more spacious ear pads that don't touch my ears, but this may not apply to you. 

 

[tehsprayer]

  What source will you be using these headphones with?  Do you have an amplifier?  What sound qualities do you want in a headphone?  The HD 650 is very warm, relaxed, and somewhat dark (somewhat subdued treble and tilted downwards), while the HE-400i should be more linear/neutral and forward in the midrange though personally I never heard it.  I'd get the HE-400i because it probably plays into my taste more, and because I prefer its more spacious ear pads that don't touch my ears, but this may not apply to you. 

Used with O2/Modi

 

[Rhamnetin]

  Used with O2/Modi

 
I see, that should be adequate for both the HD 650 and HE-400i so no problems there.  

 

[tehsprayer]

   
I see, that should be adequate for both the HD 650 and HE-400i so no problems there.  

I think i'm gonna go for HD650, but I want to find a good deal in Canada. Best I can find is $500 from headphonebar. Unless I wait for a sale and pay customs over the border...