[hackeron]

Hey,

I just got my HD600 this morning

-- I didn't A/B to my Shure E5 or HD595 yet, but overall impression is far more spacious than E5, but probably sound closer to the E5 than the HD595 overall. While I can't hear more detail in them yet (maybe I need to listen to more material), the detail I do hear though is less compressed and far less forward than on the HD595. - I'm happy

Now what I don't get is the E5 and HD595 are very efficient and can be powered by just about anything, but the HD600 need an amp.

I have the 0404 USB which from what I read has a reasonable headphone amp with 22ohm output impedance which is not great but should be reasonable with a high impedance headphone like the HD600.

However, I plugged them into my iPhone 3G and they sound, well, great! - hmm!?

The iphone has a DAC capable of 1.4V to 3.6V power and 500mW (hmm?) with 98dB SNR with 5ohm output impedance while the 0404 USB is capable of 5v with 20mW at 114dB SNR with a 22ohm output impedance.

So looking at those figures looks like indeed both should have no problems with the HD600. The 0404USB does sound a little better (but not much) - but really sound from both is very enjoyable.

Those that own the HD600, what do you think of audio straight from the iPhone and/or 0404 USB? - How exactly will a headphone amp make them sound better?

 

[Uncle Erik]

Quote:

Originally Posted by hackeron /img/forum/go_quote.gif The iphone has a DAC capable of 1.4V to 3.6V power and 500mW (hmm?) with 98dB SNR with 5ohm output impedance while the 0404 USB is capable of 5v with 20mW at 114dB SNR with a 22ohm output impedance.

500mw? Where did you find that? That sounds more like the power consumption for the charger. IIRC, an iPod gives you around 30mW, so I'd suspect the iPhone is in the same league. Listening to my 3G iPhone, I don't think there's any way it's putting out half a watt.

If you haven't heard the HD-600 with enough power, you haven't really heard it. When I ordered my HD-650 way back when - along with an amp - the HD-650s showed up first. I listened to them from an iPod and began to question why I bought an amp at all.

Then the amp showed up. It fleshed out the bottom end, had more body and there was much better control over the driver. That made the sound clearer and more precise.

 

[hvu]

For me the Hd650 straight out of the ipod sound pretty decent but it can't beat the sound of my SR80 and M50.
But when the HD650 is hooked up to a amp even a little one like the D10 there is no comparison the music has more extension and detail.

 

[hackeron]

Quote:

Originally Posted by Uncle Erik /img/forum/go_quote.gif 500mw? Where did you find that? That sounds more like the power consumption for the charger. IIRC, an iPod gives you around 30mW, so I'd suspect the iPhone is in the same league. Listening to my 3G iPhone, I don't think there's any way it's putting out half a watt. If you haven't heard the HD-600 with enough power, you haven't really heard it. When I ordered my HD-650 way back when - along with an amp - the HD-650s showed up first. I listened to them from an iPod and began to question why I bought an amp at all. Then the amp showed up. It fleshed out the bottom end, had more body and there was much better control over the driver. That made the sound clearer and more precise.

From what I could find the 3G uses the WM6180C - but I couldn't find the specs to that, just the chip it replaced, the WM8753 -- specs here: Wolfson Microelectronics plc: : CODECs - which says BTL speaker output: 500mW - I'm not sure what that means, but yeah, it's definitely not 500mw on the iphone

I'm just wondering how a headphone amp actually works?

I did a bit of research and it seems to reduce the input impedance, increase the amount of current available and compensate better for swing with higher voltage.

But from what I can find, the HD600 don't really need more than 10mW and 3.6V because of the higher impedance - so how exactly does a headphone amp help the sound?

It has to be some other way other than give more voltage/current?