**Hifiman HE-400 Impressions and Discussion Thread** - Page 174

DAC/AMP for the HE-400 update.

 

So I'll get the latest version of the HE-400 within a month and I'm already trying/buying new dacs.

 

I bought the E17 as an upgrade for my E7, and dock it the E9. 

Apparently the E17 sounds less good docked in the E9 than the E7. No need to say I'm returning the E17.

 

I recently bought the Audinst HUD-MX1. I'm wondering if the headphone out of the HUD-mx1 will be good enough to power the HE-400, or do I need to connect the HUD-MX1 to my E9? I think the later will do nicely :)  

 

I bought the HUD-MX1 from the audinst ebay shop, which is located in Korea, so it will arive in about 4 weeks.

Yes I think so too.

But I am curious how the HE-400 will sound straight out of the HUD-MX1 since it is pretty easy to drive :)

According to the specs I can see, the HUD-MX1 can provide 310 mA into a 32 Ohm load 12V power supply. We could do some calculations to guess its performance into higher impedance loads, but it is probably doing roughly 200 mA into 50 ohms, which is where I think the HE-400s actually spec.

This amounts to about 26 mWs max@32 Ohms, and say, 17 mWs max @ 50 Ohms. That should be enough for about 15dB over the 92-94dB/mW rating, so, plenty to get quite loud.

Unless I am way off, I would think it should run the headphones well under most conditions. But this would be far less power than offered by the Fiio amp.

Thanks for the calculations :)

 

So it can get quite loud, but it will not sound good right? Atleast this I had with a different usb-powered dac and my HD650. It could drive the HD650 really, really loud. But the sound quality wasn't there, no detail very bad bass etc.

 

Why is this exactly? Looks as if there is just not enough power available for those harder to get frequencies (bass). But it will run loud still because the ~ 1khz frequencies don't need as much power?

What amp did you use to drive your HD650? Over at Innerfidelity, they claim the HD650 needs only 0.13mW to reach 90 dB.

The HE-400 need 0.33mW to reach 90 dB. So, mW to mW, you need about 2.5 times the power to drive the HE-400's to an equivalent level as the HD 650. You should reach 100 dB with about 10x the power, and this is very very loud. That is about 1.3 mWs if you are using the Senns, and 3.3 mWs with the HE-400. So you can see that the main reason you need more power, or less, is about efficiency of the phones.

I don't subscribe to the idea that a "bass watt" is more difficult than a "1khz" watt. What is relevant is the resistance of the speakers and the power delivery of the amp. If an amp is "weak", it shouldn't affect bass delivery, only loudness. If the bass delivery did suck, it is more likely that the frequency response of the amp is poor, rolling off bass frequencies that you can actually hear. A lot of people probably think bass "always" needs more power, because of car and home audio. Its not that bass NEEDS more power so much as subwoofers tend to be less efficient than other drivers in a speaker system.

If you are driving a 300 ohm load with the HUD-MX1, that's about 10x the resistance occurring at 32 ohms. You would still have 2-3 mWs however - enough to drive the HD 650s, in theory, over 100 dB. @32-50 Ohms, with 26 mWs available, you might hit 108 dB with the HE-400. A bit less with 17 mWs. But the source can affect loudness to a degree, and so can amp gain and other factors. Plus, if the amp can't put out its max power without distortion, you won't make it far before the sound degrades.

The only way to know if its going to work for you is to try it. If the amp section can deliver its max power without audible distortion, or rolling off frequencies, it would seem that, in theory, it can drive the headphones quite decently. My laptop drives my HE-400s quite well, but certainly not as loud as my amp can. But they sounded about the same since the source is the same.
Edited by MrMateoHead - 11/25/12 at 4:03pm

About to buy these headphones, but I thought I would ask a few questions first. I purchased HD650s during the sale and I almost don't want to give them away because they were such a great deal. I don't have them yet, but I've been reading about how the HE400s may be a better match to my music preferences.

I listen to a lot of theatrical scores (Hans Zimmer!), Ed Sheeran, Norah Jones, Taylor Swift type of music, and then there's the electronic side of me, listening to all kinds of dubstep. I tend to favor "fun" sounding headphones, but I also want to hear the warm details in acoustic strings and female vocals.

I will also be purchasing a dac/amp combo up to $300.

Based on this information, would the HE400s be a better fit? Or should I stick to the HD650s.


ALSO, I study a lot with my headphones on, and the heavy weight of the HE400s make me worry about facing down at my textbook. Has anyone ever had problems with the HE400s sliding off their head while facing down?

Thanks!

Either is probably a fine choice. For max comfort and a great sound across genres, the Senns are probably a good choice. They will be laid back and "polite", but I have read they are also good at making mediocre recordings sound better. Others on this thread that own them can describe them better.

But I am listening to dub step right now on the HE-400s, and god the extension in the bass is delicious. They are very "fun" in my opinion, but also very balanced, and will do Norah and Hans Zimmer a lot of justice. They are excellent all-rounders, and I listen to a lot of different stuff. I like Sennheiser stuff, and give them the comfort nod, but I can't say I have liked the sound as much as the HE-400s. The 400s have an excellent ease to them, are very transparent, and can really rock out. The "darkness" and "recessed midrange" is hyperbole to me. I would say they have a great attack and slight brightness without being harsh. Feed them some good quality power and enjoy the show.

Just outta curiosity. What do you guys keep your HE-400's in when you want to carry them around?

 

The stock box really doesn't seem to be sturdy enough (thin cardboard)

I use hifiman's carrying case.

I use an Audeze case (Boo for not using the wooden cases for the LCD-2s anymore), or just pack them in a suitcase insulated with foam. I brought the HE-400s to a meet with the stock box (didn't have anything left), it sort of worked. Gotta fill it with bubble wrap and the likes.

HE400s are very close to perfect for theatrical scores and other "grand" music as well as electronic/any music with lots of bass. IMO they perform even better than my HE500s in those genres. They perform well in vocal, but not perfect - they sound too open and airy for you to get a good sense of intimacy with vocal music.

 

You might find them to be very complementary to your HD650, whereas each of the two excel in 1/2 of your music collection.

It has nothing to do with power and everything to do with implementation. You can have oodles of power and a top tier chip but if the circuit design is crud the headphone will sound like crud. Something else to note, you can have a top tier pricey amp and one headphone can sound terrible while another will sound fantastic. It's called synergy, don't ask me why it happens it just does. If you're looking for a good mobile sized amp Leckerton and ALO have nice offerings. I own both of Leckertons amps as well as the ALO RX MK II and I'm quite happy with them. JDSLabs is another dealer you can look into. The O2 amp gets lots of praise on here.

Edited by DigitalFreak - 11/25/12 at 11:43pm