[TLoFP]

So I have a pair of Phillips N6315s that I just dug up. I almost threw them into the trash a month ago. I tried them on my stereo system and they sounded like tin cans. I figured, "well it is old tech, what do you expect." Especially because I knew that my stereo system had unnatural bass boost, so for the Phillips to lack bass on the stereo system must mean that they just don't have any bass what so ever. So why am I confused? I just plugged the N6315s into the FiiO and they are amazing. I mean, wow. They are nice. OK ok. I need to listen to them more but the difference between the FiiO and the stereo system is night and day. So here is my question:
 
How can my stereo system Kenwood VR-606 make my Sennheiser HD280s incredibly boomy/bassy by an incredible amount while at the same time killing all the bass in the Phillips N6315s and making the Phillips sound like tin cans?

 

[billybob_jcv]

I looked briefly, but I couldn't find any specs on the Philips N6315 - all I found was a picture. If we knew the impedance of the headphones, and the output impedance of the headphone jack of the receiver, then that might give us some clues into what is happening.

 

[GREQ]

I'm pretty sure these are electrets.
All electrets are notoriously demanding of their main power source and will sound awful/sub-par out of almost anything.
 
I have one electret that sounds.... Ok'ish out of my fiio e17, and i need to REALLY crank up my O2 to get it singing... but really it only sounds quite good out of speaker taps.