[mikeaj]

Quote:

 
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. 

I agree that amps are overstated and often relegated to mythical status, but there are some good reasons in terms of audio performance (not just features/connectivity/being shiny) to have external amplification, with some headphones especially.

If you've got like a Beyerdynamics DT 880 600 ohms, it will take about 0.5 V rms to reach 90 dB SPL.  See Tyll's measurements:
http://www.innerfidelity.com/headphone-data-sheet-downloads
 
If you have a portable player, it can probably do about 0.5 V rms max.  90 dB max peaks are kind of low for a lot of people, for music that has a wide dynamic range.  (Granted, most music released today is victimized by the loudness wars and brickwalled mostly like -10 dBfs and above, if not higher.)  Anyway, higher impedances are easier to drive than lower impedances...at least until you run out of output voltage.
 
 
If your source has high output impedance, this can cause huge impedance interactions with low-impedance headphones (usually balanced armature IEMs), particularly those that have impedance that varies a lot over frequency.  Grab an amplifier with a low output impedance, and you'll no longer have the wacky FR shift created by the distribution of the source and load impedances over frequency.
 
 
Some integrated amps may have poor performance even when driven in a "reasonable" voltage and current range for the device, but the difference here between a poor amp and great amp is probably overstated.  However, there is some room for improvement that a dedicated amp can bring.  That is, the difference is probably small unless you prefer tube distortions or other inaccuracies/additives and consider that to be an improvement--perfectly fine by me, but let's just be clear about our objectives.

 

[jmb]

 
Quote:

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.

Just to clarify, I have used high impedance headphones, like the HD600, with portable players. Their wonderfully detailed and natural sounding musicality came through without a problem. Plugging them into an amp may make them quantitatively "better," but not qualitatively.
 
It reminds me a lot of overclocking a PC..a lot of time, money, and tweaking, for minor boosts to the quantitative performance of a game. A good game is a good game. A few frames per seconds is not going to change that in any qualitative way.
 
A crappy sounding headphone does not get better with amplification, why assume a good headphone does?
 
When going up my headphone chain (cheap to expensive) I hear significant difference in quality. I never get that same feeling when going from integrated to dedicated amps.
 

 

[winkyeye]

This is completely incorrect, ESPECIALLY for high end headphones. Sure I partially agree with you when it comes to lower end headphones that are under $500, or if you're buying headphones to just listen to music, not to pick it apart. I own a pair of ATH-W1000X and they run just fun unamped, but once you go upwards from there to low sensitivity/high impedance headphones that are designed for non-portable use, you can't say headphone amps are completely useless for them, especially since you paid a hefty price to notice those differences in the music in the first place. I'd like to see you drive the HE-6s out of your computer's audio jack when it needs ~150-400mW to run at adequate listening volumes.
 
Quote:

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. 

 
 

 

[Remonster]

This thread inspired me to try the ultimate test: listening to my new HD650s straight from my iPhone 4 and then listening to the same song (Phantom by Justice) with the same headphones off my iMac through a FiiO E7/E9 combo.
 
I've said this before and this quick little test reaffirmed my belief that the DAC (at least in my case) is more important than the (albeit fairly low end) amplifier. When I listened through my iPhone, I had to crank the volume to one or two steps below max just to get up to a comfortable listening volume, but when I went one more step up to maximum volume the dynamics were greatly improved and low end response was also better. The external DAC and amp allows me to have these dynamics (which are compressed by the iPhone or computer OS when it has to reduce the volume) at any volume and that, to me, is the single greatest benefit of having an external DAC and amp.
 
With instrumental music, there is a wider soundstage and greater instrumental separation but I wanted to focus on something simple for this five minute test so I chose Phantom which is a song I know extremely well and have heard on a wide variety of systems ranging from stock iPod earbuds, the sound systems in various cars all the way up to my Polk RTi A7 towers which I would consider the highest quality speakers in my possession.

 

[LCfiner]

Amps can make a big difference but it’s very much dependant on the headphone, of course. Some benefit only slightly, in my experience (low end or midrange grado headphones) while others benefit very clearly and obviously (D5000 bass bloat is greatly reduced when amped).
 
Headphones with lots of bass tend to benefit the most to my ears as the bass is tightened up and doesn’t bleed as easily into the midrange.

 

[mikeaj]

Quote:

Just to clarify, I have used high impedance headphones, like the HD600, with portable players. Their wonderfully detailed and natural sounding musicality came through without a problem. Plugging them into an amp may make them quantitatively "better," but not qualitatively.
 
It reminds me a lot of overclocking a PC..a lot of time, money, and tweaking, for minor boosts to the quantitative performance of a game. A good game is a good game. A few frames per seconds is not going to change that in any qualitative way.
 
A crappy sounding headphone does not get better with amplification, why assume a good headphone does?
 
When going up my headphone chain (cheap to expensive) I hear significant difference in quality. I never get that same feeling when going from integrated to dedicated amps.

(emphasis added).  I'm going to respond to the second bolded part in spite of the first, although I understand you're leaving a concession there.
 
 
Below is an incredibly simplistic and oversimplified view for the sake of example, but humor me for a sec.  The numbers below are kind of realistic.
 
Let's say you have the following headphones and amps:
Headphones A - 2% THD in the frequency range where humans perceive such things (i.e. pretty bad headphones)
Headphones B - 0.2% THD (typical for mid-high end headphones at higher volumes until they start to run out of excursion)
Amp 1 - 0.4% THD (maybe typical for some real-world integrated amps into some loads?  it's definitely higher than most real sources though)
Amp 2 - 0.001% THD (a very good amp)
 
Use Headphones A with Amp 1 and you hear the poor fidelity of the headphones.  Use Headphones A with Amp 2 and you still hear the poor fidelity of the headphones.  The headphones are the dominating factor.
 
Use Headphones B with Amp 1 and you hear the problems of Amp 1.  Switch to using Amp 2 and you will improve the setup, making the headphones more of the weaker link--at least in the very tenuous way we've defined here.

 

[scuttle]

Quote:

I don't have golden ears - in fact, it's probably lead - (I can't tell differece between HD25-I with stock cables and HD650 cables, let alone difference between Cryo interconnects and silver interconnects.
 

 
That would be because there is no difference...

 

[scuttle]

Quote:

Originally Posted by mikeaj /img/forum/go_quote.gif

I agree that amps are overstated and often relegated to mythical status, but there are some good reasons in terms of audio performance (not just features/connectivity/being shiny) to have external amplification, with some headphones especially.
 
 

 
It's pretty much this simple: if your headphones aren't clipping, then buying an amp is a waste of money:

http://tom-morrow-land.com/tests/ampchall/index.htm​

 ​

The Richard Clark Amp Challenge is a listening test intended to show that as long as a modern audio amplifier is operated within its linear range (below clipping), the differences between amps are inaudible to the human ear. Because thousands of people have taken the test, the test is significant to the audiophile debate over audibility of amplifier differences. This document was written to summarize what the test is, and answer common questions about the test. Richard Clark was not involved in writing this document.​

The challenge​

Richard Clark is an audio professional. Like many audiophiles, he originally believed the magazines and marketing materials that different amplifier topologies and components colored the sound in unique, clearly audible ways. He later did experiments to quantify and qualify these effects, and was surprised to find them inaudible when volume and other factors were matched.​

His challenge is an offer of $10,000 of his own money to anyone who could identify which of two amplifiers was which, by listening only, under a set of rules that he conceived to make sure they both measure “good enough” and are set up the same. Reports are that thousands of people have taken the test, and none has passed the test. Nobody has been able to show an audible difference between two amps under the test rules.​

 ​

When compared evenly, the sonic differences between amplifiers operated below clipping are below the audible threshold of human hearing.​

 
You can't add any "warmth" or "forwardness" using an amp that you can't add using the EQ built into a cheap DAP, nor can you add bass attack or definition. 
 
As for whether or not you are likely to need an amp in practice: a Sansa Clip+ can drive Fostex TR50s or HD25s with no problems. You have to be driving pretty awkward customers to need an external amp with a decent modern DAP.

 

[scuttle]

Quote:

This thread inspired me to try the ultimate test: listening to my new HD650s straight from my iPhone 4 and then listening to the same song (Phantom by Justice) with the same headphones off my iMac through a FiiO E7/E9 combo.
 
I've said this before and this quick little test reaffirmed my belief that the DAC (at least in my case) is more important than the (albeit fairly low end) amplifier. When I listened through my iPhone, I had to crank the volume to one or two steps below max just to get up to a comfortable listening volume, but when I went one more step up to maximum volume the dynamics were greatly improved and low end response was also better. The external DAC and amp allows me to have these dynamics (which are compressed by the iPhone or computer OS when it has to reduce the volume) at any volume and that, to me, is the single greatest benefit of having an external DAC and amp.

 
Interesting: If you are listening at matched volume levels and EQ, and the iPhone is compressing, then Apple have messed up and this is a reason not to buy an iPhone rather than to buy an amp. But it sounds from your comments about low end that you didn't EQ..
 
But to be honest I wouldn't expect an iPhone to be capable of driving HD650s properly - just through sheer lack of power in the amp to reach proper volume levels. Could this "compression" you are talking about just be clipping?

 

[PETEREK]

Beyerdynamic DT880 250/600 ohm. Unless you like your music at whisper level.

 

[kfki]

The reason I bought an amp in the first place is because I want to enhance the bass & treble. I don't need loudness, my 535s are pretty loud to me. 
If you pair with up a an average source player like 10 to 50 bucks mp3 player. They will sound terrible. You need a good source to go with the amp, plus you need a decent pair of headphones to make the magic happen. So at the end an amp is like a lifestyle which you tell people you're a hardcore audiophile who needs to hook to sophisticate looking machines to make music sound good. I was deceived by the idea. Honestly it doesn't make much of a difference with my 535. The bass is tighter which I think. 
Since I had the E07K for a week, I can't return it, so is there way I can use beside hooking up to my portable mp3s. Can I hook it up to my micro-chain stereo? 

 

[kramer5150]

HD580/600
K701/2
 
None of these cans sound very good unamped... no myth... straight up fact.

 

[AzN1337c0d3r]

Quote:

HD580/600
K701/2
 
None of these cans sound very good unamped... no myth... straight up fact.

I own a HD600, HD650 and a K702 and can confirm this. Everything sounds so muddy without an amp.

 

[Happy Camper]

Every device with a headphone jack uses an amp so to say you don't need one is simply wrong. How much of an amp is needed may be open to discussion but you do need an amp to drive a load.

I recall when I first came here, I bought a Xin Macro 4 with 8620 opamps & dual 634 buffers. I was very content with my 701s. I got caught up in the hype and bought a Single Power headphone amp with some bells and whistles for a little over $2k. The immediate comparison was very disappointing. I felt I wasted my money and got nothing for it but a bunch of boutique parts and so took a pessimistic view towards the hype. But I started to learn how to listen and found out loudness is only part of the picture and once the amp was burned in and used for a while, I went back to the Xin and started noticing some subtle differences. More impact, defined imaging, tighter bass and treble that didn't sizzle. Then I got into tuberolling and again was surprised by the subtle but noticeable differences in tubes. Then came ICs, power cords, power treatment, software setups, etc. The value of those subtle differences is debatable but you will notice better performance with better quality gear. Typically, that equates in higher cost.

But the headphone's need for power is very dependent on the headphone. The K70x was a lock to use better amping. The RS-1s didn't have as big a demand for amping so didn't scale as well. The next purchase was the HE-6 and suffice to say that was the most demanding and rewarding of all my experiences and it took a lot of searching and experimenting (which continues today) to find an amp that can make the HE-6 shine. They need power and that only comes from amps, not sources. This statement will cause some debate but every component in the chain is as important for it's function as the rest of the components. Putting a more expensive amp on a lessor source will not make the source sound any better. Buying a more expensive source may not necessarily improve the sound if the amp and headphones are already at their max capability. So there needs to be room for improvement before the investment is justified.

I see people buy the top end headphones and then drive them with less than optimum results and wonder what everyone else is hearing that's so impressive. Typically they will move the headphones out and settle back into their comfort zone, never taking the effort to try better gear to judge. I've read many a discouraging comments on the HE-6s because they were underamped and people just defy any advice based on their limited efforts. I'm singling out the HE-6 because that's my experience but the story can change the model and read the same.

Sum.- each headphone has their own needs and cover statements like this topic just confuses newcomers. It's wise to take all the glory talk with a healthy shaker of salt as FOTM gear is always better in print than it typically is. But when the experienced guys start fluffing a piece of gear, I'll take notice. The GSX II is one example.

 

[p a t r i c k]

All headphones need an amplifier of some sort of course whether it is built in to a computer or other device, or if it is a separate or dedicated amplifier.
 
So the question really is about how important is the quality of the amplification.
 
In most people's setups the biggest area, by a wide margin, for losing the original signal is the headphone itself. The transducers in the headphones lose a great deal of information as do the design of the phones, so that is the place which needs the most attention.
 
I think that in today's setups the next area of loss is the amplification. With the amplifier there is an input circuit and an output circuit. The output circuit is ideally to have the same signal as the input circuit but with more power. This is still quite difficult to do very cheaply so the amplifiers supplied with computers and other devices often do lose some information. However this is not as great as the information lost by the headphone itself.
 
Using a higher quality amplifier will reduce information loss. If the user is not seeking out very high quality then they won't notice a significant difference between the good amplifier and the not as good one.
 
I think that there are many very good budget separate solid state amplifiers available for headphones these days and with one of these allied to an acoustically transparent headphone a remarkably high quality of sound reproduction can be achieved.