need advice for first headphones - Page 2

I would look into the Q701s before they ship, they have better positioning for gaming, Amp and DAC wise, you need an amp but your card is an acceptable dac, get an O2 from JDSlabs (USA) and you can drive nearly any headphone (no electrostats or AKG-1000), its about 150 bucks and an amazing little piece of electrical wizardry. use a 3.5mm line from your soundcard to the O2 and set the soundcard output to 100% with no volume boost, when listening to music use 2 chanels 44.1Khz (unless you have higher sample rate music, unlikely) and when watching videos or movies go with 6 or 8 channels and games 8 channels

ok let me explain this... with physics!

P=IV (power = current * voltage)
RT= SUM: R1-Rn (Total resistance = sum of resistors in series)
V=IR (Voltage drop = total resistance * current)
So lets say for comfortable listening levels your 600Ω Beyros need 60 mW (mili-watt) of power (maximum is 100 mW), you'll probably want a little more to be safe as well.

This means they need .06W+ of power, quite alot considering the size of the drivers

with a very high resistance of 600Ω this means they need quite alot of voltage at a lower current to work properly (high voltage drop) (R=I/V)

P=IV V=IR

P=I²R

.06W=I²*600Ω
.01A=I

V=IR

V=.01A*600Ω
V=6

So you need .01A and a whopping 6 volts to drive your headphones comfortably.
This may not seem like alot when looking at motors and appliances but in the headphone world it is quite a bit of power and must be delivered cleanly and efficiently, and I would be extremely surprised if the Auzentech could deliver anywhere near that level of power without serious fluctuations. Now you could plug the headphones in and it will work, don't get me wrong, but they will be getting nowhere near the proper voltage they require for optimum listening and will be straining the card quite a bit.

So simple answer is yes, even though the specs of the card says it can go to 600Ω it is not really a good idea to use an internal soundcard for these kind of headphones, they're really not made to drive levels this high, if it were <200Ω I'd say you'd be fine, however you should get an amp to get the most from the $300.00 headphones you're buying.

The Amp that I would recommend (and use hours a day ) is the Obejective 2, or O2. It drives my 300Ω HD650s better than my xonar DX or Fiio E-7 (or ipod lol) my a huge margin. It can be bought from JDSlabs (where I got it) for $156.00 with the AC to AC adapter(best just to get it because it is a rare kind). The DAC (digital to analogue) section of your soundcard is quite good and you do not need an external one, so get the O2 and use a decent 3.5mm cable to connect them and leave the soundcard's volume at 100% for line out (make sure it's line out and not 'headphones', idk the specifics of the control center for your card) and control the volume with the amp. The sound card digitally controls it so it degrades the sound and as it is easy to avoid it's best to.

Hope this helps, they're good cans, my friend has a pair, more comfortable than the HD650s but don't sound quite as good IMO, however HD650 prices went way up after the HD700 release so they're not a good value anymore. Good luck with it:thumb:
Edited by rdrdrdrd - 5/12/12 at 11:44pm

The headphones (DT 990 600 ohms) are around 600 ohms, a bit higher or lower depending on the frequency. Pretty much any kind of cheapo solid state or even many tube amplifiers will have no troubles driving 600 ohms with low distortion, at least until the point of clipping. This includes whatever is in most sound cards.

As for volume, you're looking at the headphone impedance, how much power the source can put into that impedance (for every device, the max output power is a function of impedance), and the sensitivity of the headphones. Those are around 93 dB SPL (sound pressure level) / 1 mW power input. If you want to listen no louder than 93 dB, all you would need is something that can output 1 mW into 600 ohms. If you wanted to be able to hit peaks of 110 dB SPL, that would require 17 dB more, which is 10^(17/10) = 50 times the power, so about 50 mW instead.

110 dB SPL is really excessive unless you're listening to some classical or jazz recordings with a very wide dynamic range (so the average volume is much much less than the peak volume).

The Auzentech card advertises being able to output around 3V, so that would be about 15 mW into 600 ohms for about 105 dB SPL max. For some people that's probably enough. For others, maybe not. It depends on how loud you listen, and what kind of recordings. Most music nowadays is mastered with a very loud average volume and would be plenty fine with something like that. btw if you just get the 250 ohms headphones version instead, that's about 4 dB louder at any given volume setting (the volume setting sets a different voltage).
Edited by mikeaj - 5/13/12 at 1:21am

buy my dt770 pros from the marketplace!!!

I'd go for the amp, but if you're skeptical then get the headphones and try them with the card and find someone in your area that sells or has amps and try one out, if the difference is noticeable to you then get an amp. If you get the 250Ω then you could get away without the amp I'd say.

It's a wonderful little piece of engineering, report back to us when you get it