[Herandu]

The K701 cannot be 64 ohms impedance, no matter what AKG says. I believe it is more like 600 ohms. The resistance might be 64 ohms, but not the impedance. The reason I say this is because the K701 is only half as loud as the 300 ohms HD650.
I was going to dispose of my K701 until I decided to try it on one of my amplifiers that has tone controls etc. Without using the tone controls, the K701 registered little increase in bass. It do however work properly this time with the output VU meters showing that the amp was delivering more than 100W into 8 ohms! I can turn the tone control up on the K701 by 6dB in order to get real bass with real impact.
I tried the K701 on scores of headamps etc., but it only works properly on my 85W(8 ohms) amp. This is not what I expected, and my view on the K701 is not changed. They are not suitable for anyone who doesn't have a POWERFUL headamp to drive them.

 

[MatsudaMan]

I would have to say that if you want a pair of headphones that don't need an amp, look no further than Senn px100 or Koss Portapro. Yes, even these humble headphones respond well to amplification, but they still sound excellent out of a dap. I would have to agree that even grado sr125's sound soooo much better through an amp - but then again, I never take my grados or hd580's out for a walk - just grab the px100's and my sony dap, and I'm good to go!

 

[Navyblue]

Quote:

Originally Posted by Herandu /img/forum/go_quote.gif The K701 cannot be 64 ohms impedance, no matter what AKG says. I believe it is more like 600 ohms. The resistance might be 64 ohms, but not the impedance. The reason I say this is because the K701 is only half as loud as the 300 ohms HD650.

As mentioned above, impedance alone doesn't actually says how loud a can is. Low impedance doesn't mean low power requirement. The other number you should be looking at is the efficiency rating, the K701 might have a terribly low efficiency.

 

[Agnostic]

If anyone is still looking for headphones that sound good without a dedicated amp in this thread: ATH-ES7.
I've heard them powered by:
Ipod 5g
Headstage Lyrix pro
Microshar uAmp 107b
Xiang Sheng 708B (tube rolled)
Graham Slee Solo

It sounds great out of all (to my ears). It does sound slightly different but that is more a matter of taste than a matter of quality. Personally I prefer the coloration of the uAmp.

Incidentally, this leads me to a misunderstanding I have seen in this thread a few times and more generally on Head-Fi: Amplification can do two different things:
1. Make a headphone sound objectively better: i.e. improved control, lessened harshness, better detail and speed, improved tonal balance.
2. Make a headphone sound different: color the sound in a way that is pleasing to certain listeners.

Those two account for a lot of confusion and misunderstandings here on Head-Fi I think, partly because it can be hard to distinguish between them sometimes.

While people will generally agree on type one, differences of type two may sound a lot better to some people, while others hear hardly any difference in sound quality with the same setup.

A difference in sound signature may not sound spectacular to you if the two sound signatures in question do not coincide with your personal tastes: They will end up sounding equally good, but different. This is simply because what you are hearing is not an objective improvement but a change.

However, a change may sound like an objective improvement
and even quite spectacular one if it coincides with your taste.

 

[braddo]

Quote:

Originally Posted by Nomad /img/forum/go_quote.gif Unfortunately the amp improves things by a (very) large margin. When I first came here I remember I was trying to fool myself thinking that they weren't that required. They are. The only headphone that didn't improve that much with amps was the UE-10, and still, the effect of a good amp on them was noticeable. The 595 sounding great without amp is a myth. I was listening to it yesterday unamped and it was OK. I've been listening this morning from a Earmax Pro Aniv. Edition and they were truly remarkable. I had the R10s on sight but I preferred to keep using the 595 instead, that's how much I was enjoying them. Sorry to say this, but it is true to my ears and I don't think it is just an audiophile thing. I recommended headphones to several friends/colleagues for unamped use (mostly SR-225, HD595, ESW9... depending on circumstances/preferences/budget) and when they come to my place and they listen to them amped (with same source for reference, a humble ipod) they are always amazed about how the sound improves. Only a couple of them didn't find that much difference, but then again I know them and I wouldn't take their word for pretty much anything, with all due respect. Depending on headphones, Bass, or Soundstage, or Presence, or Detail, or Mids, or some or all of them at once get a dramatic improvement with the right amp. That sucks because I don't like to carry an extra amp for portable use and I have to settle with a suboptimal sound. Qualias, Grados (not HPs), L3000s, ESW9s, and HD595 are quite OK unamped, until you listen to them with good amplification, of course. Even a humble PX-100 sounds quite better from the right amp. If you want to go unamped, IEMs will be your best bet, but they can be tricky to wear, especially for long period of time.

Great. I find 595's incredible at times, almost faultless. Sounds weird even to me but it's true. With the right gear/music (rock/pop) these things sound very good. I own expensive vintage musical equipment so I hear great sounds all the time, and 595's cut it for the money

 

[silverrain]

Quote:

Originally Posted by whee /img/forum/go_quote.gif I'm not sure I understand. the ultra is a dedicated home amp shrunk into a micro form factor. it uses headroom's max module. it runs off a dedicated power supply only (wallwart or upgraded astrodyne). its got nothing to do with a portable amp and its definitely got enough juice to drive any headphone, especially k701s. I don't see how the ultra is in any way a "portable" amp. the ultra micro the standard micro the portable micro

That's right.
The Micro amp has "morphed" into a tiny powerful desktop amp, with very good electronics.
And a portable version is still available, too, just like with the Desktop model amp.

 

[uraflit]

i think amps are bogus. complete waste of money... aka. placebo machines to get some money for the sellers by luring all the suckers that fall for "better" sound

of course, i'm joking, but it would be a cool idea no? it would save us a bit of money =D

 

[regal]

You can't listen to headphones without an amp, it is not possible.

 

[ronnielee54]

I am a firm believer that all headphones benefit from proper amplification. I can tell a difference in improved Sq even in my PX100's and KSC35's when they are run through me AE2. To me an amp adds a fullness to the sound. Not just louder.

 

[shomie911]

The DT880s need an amp like you wouldn't believe.

I can get a lot of volume out of them through my Ipod Nano but it just sounds bad, better than Ibuds, but nowhere near the full potential of these heaphones.

The entire bottom end of the sound signature is nonexistent and the sound is cold and uninvolving.

But amped, they sound amazing.

Definitely in the same league as the HD650, just more balanced, for those who like that kind of sound.

Which would be me.

 

[Anticrash]

All headphones benefit from proper amplification? Even my HD 280s (64 ohms), which are great starter headphones but nowhere nearthe quality of some good open cans like the HD 600s or K701s?

 

[Dobro]

Quote:

Originally Posted by Anticrash /img/forum/go_quote.gif All headphones benefit from proper amplification? Even my HD 280s (64 ohms), which are great starter headphones but nowhere nearthe quality of some good open cans like the HD 600s or K701s?

If by proper amplification you mean enough power to avoid clipping and to provide proper control, then the answer is yes. However many headphones don't need any more power then is provided by the the headphone out on your source and many of these don't really benefit from improvements in application. Judging from the 280's low impedance and high sensitivity as well as the experiences of others, I would assume that the HD280s are among those that neither need nor benefit much from amp upgrades.

 

[xFih2]

Quote:

Originally Posted by Anticrash /img/forum/go_quote.gif All headphones benefit from proper amplification? Even my HD 280s (64 ohms), which are great starter headphones but nowhere nearthe quality of some good open cans like the HD 600s or K701s?

Based off of experience (I own a pair), I would say don't bother with an amp. You could always get an amp and get a different pair of headphones later down the road, though

 

[jmb]

I will resurrect this long dead thread to put my two cents in.
 
I think headphone amps are completely unnecessary. In my experience they simply modify the headphone's sound signature and add some volume. I have never had a "better" listening experience going with a line out feed to a dedicated headphone amp. If you like to tinker with how your headphones sound, they are fun, but anyone thinking a dedicated amp will have a significant impact on how good their headphones sound will be disappointed. They will certainly change how the music is presented, but your favorite song will sound as good either way, as long as you like the headphones you are using and the file is not overly compressed.
 
I just plug right into my devices these days and enjoy. The only time I miss a dedicated amp is when listening to the old classic rock stereo recordings. The channel separation is sometimes so extreme it becomes fatiguing and it makes me want to add a little crossfeed.
 
People are often counseled that buying an expensive high impedance headphone is a waste without amplification. It is the single biggest fallacy that permeates this community. Good headphones sound good, even plugged directly into a portable. 

 

[Graphicism]

Quote:

I will resurrect this long dead thread to put my two cents in.

The problem is people who come to this assumption arrive there because the headphones they have don't happen to really benefit from amping. In addition if you have a slew of cheap headphones you are likely to introduce a cheap amp which I would also question does it do much apart from volume? Inadvertently by saying you don't need an amp you also aren't bothered about sound quality as you're also using the built in DAC.
 
None of the headphones in your sig benefit from amping, in fact they are commonly referred to those looking for headphones without the need of amplification.
 
In closing whatever device you use, be it a soundcard or CD player, if it has a headphone out it has a built in amp of some sort.