Utkarsh97Alright, so for the HIFIMAN it doesn't need an amp, but the Sennheiser HD6XX does? And for the amp, do you have any recommendations? (If you have any recommendations.)
keiidenA amp will help to really get these sounding nice but I'd say the Schiit magni or the JDS o2 amp or the Massdrop O2 amp would be good if it's still open
keiidenUmm, I would almost demand getting an amp. Low impedence, but also low sensitivity. When Massdrop says you can run it off a phone only, technically that is true. But even with my Fiio E17k, I'm not driving these nearly as well as they deserve. You NEED amplification on these cans...
keiidenI have both and prefer the 4xx to the 6xx's. The 6xx's are good, but I prefer the 4xx's more open sound, and think the full frequency range from the treble down to the bass is equal to or better on the 4xx's. To me the 4xx's are a more fun headphone to listen to. The 4xx's don't need quite as much power as the Sennheiser's, but I do recommend a good amp. I'm using a Ray Samuels Hornet portable amp.
Utkarsh97That's completely wrong. The HD6XX need much LESS power than the HE4XX. And the difference is HUGE, like 10 times less power, I checked it. On the other hand, most low cost solid state amps provide much more current than voltage, so they'll provide way more power under low impedance loads than on higher loads. That's why some people says that their amp struggles to drive the HD6XX: not because they need a lot of power, but because their amps are not able to provide almost any power under a 300ohm load. If you wanna check how much power do a headphone need to be driven to a certain loudness level, check here: http://www.digizoid.com/headphones-power.html
keiidenWrong, both need an amp to sound good (and loud enought). It's not audiophile BS, it's true, believe me or not. Low impedance high sensitivity headphones, like Audio Technica ATH-M50x (38 ohm, 99dB/mW), CAN be driven by most high-end smartphones to reasonable levels but they'll still benefit from an amp. Hifiman HE4XX have low impedance but also low sensitivity (35 ohm, 93 db/mW), meaning they NEED an amp to sound reasonably good. I tried plugging both my Fostex T-X0 (planars with similar impedance and sensitivity to the HE4XX) and Sennheiser HD6XX straight to my phone, and the HD6XX sound louder but both don't reach a decent level and sound SOOO BAD (again, believe me or not). If you wanna check how much power do a headphone need to be driven to a certain loudness level, check here: http://www.digizoid.com/headphones-power.html
Long story short, both need an amp, end of story.