[rodweb]

	Power Rating	Efficiency	90dB SPL	105dB SPL	120dB SPL
HE-4	2W	86	2.30mW	72.68mW	2300mW

Got bored and did some calculations. Based on this data when you interpolate in an exponential graph you will see that you can get about 110dB SPL at 650mW with the HE-4. If I am interpreting this correctly this means that the minimum power required to get optimal performance out of the HE-4 is 650mW since at an 80dB listening level (Where your ears are most accurate and music sounds the best without too much risk of long term hearing damage.) you get about 30dB of overhead for dynamic range meaning unless you are listening to some insane orchestral stuff you aren't ever going to run into a dynamic range wall.

It's actually around 4mW for 90dB, 126mW for 105dB and 4W for 120dB.

Edit: considering 42 Ohms

 

[Rinx7]

I thought the impedance was 38 ohms on the HE-4

 

[Rinx7]

Doesn't actually end up changing things much when you interpolate it SPL at 650mW ends up around 108dB.

 

[rodweb]

I thought the impedance was 38 ohms on the HE-4

I'm not sure, I saw it somewhere..

 

[Soundsgoodtome]

What line out level do you need to achieve that spl with that power?

 

[Makiah S]

 

	Power Rating	Efficiency	90dB SPL	105dB SPL	120dB SPL
HE-4	2W	86	2.30mW	72.68mW	2300mW

 
Got bored and did some calculations. Based on this data when you interpolate in an exponential graph you will see that you can get about 110dB SPL at 650mW with the HE-4. If I am interpreting this correctly this means that the minimum power required to get optimal performance out of the HE-4 is 650mW since at an 80dB listening level (Where your ears are most accurate and music sounds the best without too much risk of long term hearing damage.) you get about 30dB of overhead for dynamic range meaning unless you are listening to some insane orchestral stuff you aren't ever going to run into a dynamic range wall.

 
 

What line out level do you need to achieve that spl with that power?

Indeed indeed 

 

[Rinx7]

Assuming that the impedance is purely resistive I could calculate that for you.

 

[Soundsgoodtome]

Sounds good. What's the norm, 2V? Then there's mastering levels I guess but just from pure numbers and gear would work.

 

[Ron12]

I've tried to catch up with the thread... Some things to add:
 
1) You don't have to use specifically Beyer pads's fillings in order to mitigate that slight edginess in treble... Similar materials used for modding the HD800 are good enough (felt or rug pad or similar). Felt is going to make HE-4 very slightly warmer (still a good portion of air and quite nice imaging, just a little bit warmer signature with more impactful sub bass) while rug pad is not gonna change them at all (only very slightly decrease the edginess). Try to do that instead of changing pads from stock... Not worth it unless you really want to alter their FR.
 
2) I would really call the HE-4 a perfect downgrade headphone from the HD800... I was always thinking about HE-500 but once I found HE-4, I knew these are perfect for me. Better than DT880, K712 Pro, HE-400, HE-500 etc. HE-4 are like a perfect fusion of Hifiman's timbre+ortho bass and HD800's airiness, soundstage, speed and detail. Mids are not recessed subjectively - rather accurate, not lush but not recessed. They are not perfect (imaging is not HD800's like, there is some increased level of distortion in lower treble)... But for anything up to price of HE-500, they are a steal. The best value-for-money headphone I have experienced so far... And I agree that I would seriously hesitate to buy HD800 again now that I have the HE-4.
 
3) The treble of HE-4 is different from the one of DT880... And bass is different as well. Timbre is also way too different to even compare those two and call them more or less the same. HE-4 are significantly better. I mean - I prefer HE-4 even to LCD-2 rev2 while DT880 are definitely not on the level of HE-500 or LCD-2.
 
4) They are not so hard to drive... They have single-ended drivers and comes with a 3.5mm short cable for portable usage. Yes, I would not use them with my smartphone but I tried to plug them once and listen to a song or two - and they sounded good that way. Harsher, with rather badly defined soundstage but bass was still tight and the overall sound completely listenable. Of course, my Yulong DA8 (in both balanced and unbalanced mode) gives better results but I would never call HE-4 a very-hard-to-drive headphone. I've tried many headphones and yet the bass is one of the best I've ever heard and they do not sound harsh at all from the Yulong so I don't think I am underpowering them at all.

 

[Rinx7]

I agree people severely overrate the difficulty of driving the HE-4 if you do power calculations it seems like unless you are listening to music with insane dynamic range about 550-650 mW is plenty. If their sound is that similar to the HD-800 though I would guess that they sound really good out of warm tubey amps. I wish I had enough money to afford a Woo Audio amp of some sort. I think it would be a match made in heaven.

 

[Soundsgoodtome]

  I agree people severely overrate the difficulty of driving the HE-4 if you do power calculations it seems like unless you are listening to music with insane dynamic range about 550-650 mW is plenty.

Including Fang from Hifiman himself.

 

[Makiah S]

  Including Fang from Hifiman himself.

THe problem isn't the quanity of power, but the quality. It think it's a correlation, but it seems that higher powered amps often has less distorition and an overall more balanced sound, due to the design of the amp, 
 
but to quote Jason Schiit "You can never have enough power" and you can check the Schiit Happened post about his thoughts on Balanced Amps :3 he feels, like me, at the end of the day they offer a better quality of sound... oh and at least double the power

 

[Ron12]

  I agree people severely overrate the difficulty of driving the HE-4 if you do power calculations it seems like unless you are listening to music with insane dynamic range about 550-650 mW is plenty. If their sound is that similar to the HD-800 though I would guess that they sound really good out of warm tubey amps. I wish I had enough money to afford a Woo Audio amp of some sort. I think it would be a match made in heaven.

 
I would say that HE-4 is like a HD800 with deeper and more impactful bass and therefore feels subjectively slighly darker... The great thing is that the bass is absolutely tight (hello HE-500) and not overly hardhitting (hello HE-400). At the same time, I can understand while people call them slightly U-shaped... It's not like mids are not there but if you listen to music, subbass and that airy and detailed treble is what catches your attention. Mids are there, completely present and full-scale... But they are not lush like with LCD-2. But they are also not recessed like with D7000. Something in between - I would say subjectively dead-neutral, accurate.
 
Yes, tube amplifiers could work well... But I am personally not a fan of tubey sound. Therefore slightly warmer SS amp/DAC (like headamp and balanced pre outputs + slow DAC filtre of the DA8) work nicely as well. My observation is that their treble is absolutely great with darker AND neutral-sounding tracks... But with significantly distorted/compressed or overly bright-mastered ones, you will most probably notice the emphasis.
 
I like the airiness of the HE-4... Not as airy and spacious as HD800 but in comparison to every other ortho I have heard, they just offer a great soundstage! I haven't heard the HE-6 or Abyss though. And not planning to because after several years of high-end headphones listening, I found this special headphones... And I am completely happy and not feeling like missing anything. Seriously.
 
HD800 are still the best for me... But they get crushed in terms of price/performance ratio by the HE-4. So do many other headphones... if not all of them. And btw, comfort is very nice - that reduced weight makes them very comfortable for long-term listening... Including headband.

 

[Sorrodje]

RInx7 & Ron12 : +1 . Your statements are fully confirmed by my own experience. the HE-4 is imo too the best downgrade for HD800. the biggest downgrades are a slight lack of refinement a imaging & a harsher upper treble but overally I found that these headphones share similarities.  On paper , the HE-4 need 0,7 W tio give full dynamic range at a 90db volume. I haven't any problem with a Vali or a Jdslabs O2 for example. I had my best results when I paired my HE-4 with my MG Head tube amp.

 

[.Sup]

RInx7 & Ron12 : +1 . Your statements are fully confirmed by my own experience. the HE-4 is imo too the best downgrade for HD800. the biggest downgrades are a slight lack of refinement a imaging & a harsher upper treble but overally I found that these headphones share similarities.  On paper , the HE-4 need 0,7 W tio give full dynamic range at a 90db volume. I haven't any problem with a Vali or a Jdslabs O2 for example. I had my best results when I paired my HE-4 with my MG Head tube amp.

I agree. I more often use HE-4 instead of HD800 because of the bass quantity which is just perfect for me. The dark sound also appeals me, very smooth too. I prefer leather pads which make them less bright than the velour and SS amp makes them sound very energetic. They are certainly not hard too drive.