Debunking Amp Myths for the AVERAGE headphone listener... What headphones really need amps??? - Page 9

Quote:

Originally Posted by jmb 

 

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.

Quote:

Originally Posted by Graphicism 

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.

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:

Originally Posted by 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. 

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.

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.

Quote:

Originally Posted by jmb 

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.