[Yoga Flame]

 
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I don't know about the other 2, but the Schitt Lyr is designed for low impedance and low sensitivity.  The gain is way too much for a headphone like the OP's.

Agreed. Both impedance and sensitivity need to be taken into account when choosing tube amps. Too much gain would mean the sound gets too loud even by turning up the volume knob only a little. Often, it is accompanied by channel imbalance due to most volume pots having poor tracking at the lower levels.
 
The Little Dot 1+ has adjustable gain, so that may be more suitable for the OP. Never owned one myself though, so I'm only speaking generally here. (But I do have a Bottlehead Crack and can wholeheartedly recommend it for high impedance headphones.)
 

 

[eljaguario]

How about something like an E7? DAC vs new sound card, which one will bring me better sound quality?

 

[DaBomb77766]

Quote:

How about something like an E7? DAC vs new sound card, which one will bring me better sound quality?

Depends on what you'd be using it for.  If it's for low-impedance headphones, an E7 would be better than something like an onboard soundcard, since I think most soundcards tend to have a  higher output impedance.  They're designed for headphones that have a higher impedance.  I could be wrong though.  But I think the Xonar Essence has somewhere around a 10 ohm output, which is quite a bit higher than the near zero ohm output the E7 has.
 
Still, I like external sound cards more, they tend to be more versatile.

 

[eljaguario]

Maybe a stereo amplifier could work?