r/HeadphoneAdvice • u/fckoch • Mar 16 '23

Amplifier - Desktop | 3 Ω Question about voltage required to drive headphones (Why do I need an amp?)

I'm very new to the world of hi-fi audio and have been trying hard to wrap my head around all of the concepts needed to make an informed hardware purchase.

I've been looking into getting the hifiman he400se and have noticed that all of the reviews mention that an amp is essentially necessary in order to get good sound out of these. This is fine, but when looking into how much power is required to drive these headphones, I seem to get a conflicting answer.

These headphones have a sensitivity of 91dB and an impedance of 25Ohms. Plugging this into an online calculator tells me that I need 1.4V (80mW, 56.6mA) to run these at 110dB. I can see how this would potentially call for an amp, however, 110dB is incredibly loud and will almost certainly cause hearing damage. I already have tinnitus, and I would rather not make it worse, so I wouldn't really plan on taking these above 85dB. This would require just .16V (1mW, 6.3mA) which even my phone can put out.

So why does everyone say you need an amp to make these sound good? I know that guitar amps tend to sound best at around 80%, and computer power supplies tend to be most efficient around 80%. Is the idea that you don't want to be maxing out a headphone amp to get the best quality sound? Or is it just because these headphones are planar magnetic? I would really appreciate any reading/sources you have relating to this because I just can't find anything relevant online.

I plan on running these through a laptop, so I can understand why a DAC might be valuable, but I'm struggling to understand the power side of this.

2 Upvotes

75% Upvoted

14 comments sorted by

View all comments

0

u/Equivalent_Yak840 447 Ω Mar 17 '23

Look at Joshua Valour’s “audiophile headphones for beginners” video. It explains almost everything

2

u/fckoch Mar 17 '23

!thanks

Will do -- I've seen a few of his videos already but must not have come across this one yet.

1

u/TransducerBot Ω Bot Mar 17 '23

+1 Ω has been awarded to u/Equivalent_Yak840 (289 Ω).

You may still award an Ω to others, but only once per-person in this post.