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high impedance headphones need a dedicated amp to sound good... please can we kill this myth? - Page 3

post #31 of 59
Thread Starter 
Quote:
Originally Posted by wakibaki View Post

 

You need to work on your cynicism a bit.

 

50 years ago 'hi-fi' was all science-based. Now 99% of 'audio' is mythology. Apart from the stuff bought by ordinary consumers who have the good sense to know hype when they see it. I don't mean Beats by Dr. Dre.

 

I don't like it any more than you do, but there's no sense in getting your knickers in a twist. Let it all wash over you.

 

w

 

50 years ago people listened to vinyl and tube amps. Now you can buy a $50 sansa clip+ and it will sound better, hold all your music, and fit in your pocket... I think we have made progress.

post #32 of 59

50 years ago, if you had tried to insist your 'listening impressions' took precedence over the measured results you would have been mocked without mercy. It's not all been progress.

 

w

post #33 of 59
Quote:
Originally Posted by Eisenhower View Post

Unlike the cable myths, nobody ever calls anyone out on this one. Granted, there is more truth to having a good amp, but it certainly doesn't warrant the incessant demand that everyone remotely concerned about sound quality must use a headphone amp always for any headphone impedance > 50 ohms or whatever, when the opposite is more likely true.

 

LOL!

Gotta say I agree with you on this one!

Especially the part about the cable myths.

Everyone likes to pick on cables, but don't mess with those "powerful" amp myths!wink_face.gif

 

Quote:
Originally Posted by wakibaki View Post

Headphones may be insensitive. They may have a high impedance, or an impedance that varies a lot with frequency (most vary to some extent).

 

Headphone outputs can have problems driving headphones (to an adequate volume or with a flat frequency response) because of:

 

1 Inability to source sufficient current.

 

2 Inability to achieve sufficient voltage swing.

 

3 Too high an output impedance.

 

4 Any 2 or 3 of the above in combination.

 

Very rarely some headphones perform better with a high output impedance (some are designed to operate with 600 ohms out, an old standard), but an amplifier with good voltage and current capability can be made to appear as a high driving impedance by using a series resistor, whereas nothing can lower output impedance, or improve current or voltage performance other than an amplifier (OK, a transformer can, but let's not go there).

 

A headphone amplifier is not necessary in some instances and will not be an improvement in some instances, but often it will. It's the difficulty of defining and understanding the circumstances in which it will be an improvement that makes it a good recommendation in general, if the amplifier itself is of good quality (has good current and voltage and low output impedance in combination with low noise and distortion).

 

Put simply, it's easier to recommend trying a good amplifier than to explain to a naiive consumer with phones and a DAP of unknown quality how to figure out if he needs one, and owning one has the advantage of opening up the range of headphones he can expect to use successfully should he decide to buy different ones in future, so it's often chosen as an easy recommendation without any intent to mythologise.

 

w

 

Sure, try explaining to a novice the concepts of power, voltage, current, load impedance.

Easier to say: you need to buy another box!

post #34 of 59

End of the day, those who dont want to buy an amp dont have to - those of us who see value in buying a dedicated headphone amp or a vintage receiver will do so anyway. We arent talking crystal pyramids on top of a pair of speakers here .....

post #35 of 59
I'd say low and high impedance headphones both need an amp to sound good, because headphone outputs on most devices are bad.
post #36 of 59
Quote:
Originally Posted by RazorJack View Post

I'd say low and high impedance headphones both need an amp to sound good, because headphone outputs on most devices are bad.

 

That's probably the most realistic suggestion I've heard. Although the scientific explanations about impedance, sensitivity, and power etc. all make complete sense, it doesn't explain the fact that most headphones/earphones sound pretty average out of an iPod Classic (for example - not iPod bashing). A good aftermarket amp will almost always be an upgrade unless you start with a quality player like Cowons, iBasso, HiFiMan, etc.

post #37 of 59
Quote:
Originally Posted by RazorJack View Post

I'd say low and high impedance headphones both need an amp to sound good, because headphone outputs on most devices are bad.

 

I wouldn't call them "bad" - a more accurate term would be that they are designed with too many "compromises" so at least we can get into the details as to why that is. Size to fit in the same chassis, power supply design for the entire device plus battery life if its a portable, all can make for some noticeable inadequacy in driving many headphones, even earphones (too low impedance, still needs tons of current if at least for an earphone, etc). But what I don't understand is how many might find too many of such devices "unlistenable" (some may have penned that they just took off their headphones in disgust [sic]); or maybe I'm more forgiving despite the fact that I notice clear improvements because most of my listening through more demanding headphones without an amp happens during a power blackout and I'm just happy enough to actually be listening to them at all. Ditto for when I've compared portables vs desktop amps.

post #38 of 59
Quote:
Originally Posted by Loquah View Post

That's probably the most realistic suggestion I've heard. Although the scientific explanations about impedance, sensitivity, and power etc. all make complete sense, it doesn't explain the fact that most headphones/earphones sound pretty average out of an iPod Classic (for example - not iPod bashing). A good aftermarket amp will almost always be an upgrade unless you start with a quality player like Cowons, iBasso, HiFiMan, etc.

 

The funny thing is that the iPods and iPhones perform better than many players of the companies you mentioned. Random examples: they don't have that bass roll-off like the Cowons, have a lower output impedance than the HM-801 and no treble roll-off, lower noise, less distortion especially into low-impedance loads, better stereo separation ...

 

The only big limitation I see is the voltage output, but many other portable players are quite limited there too.

post #39 of 59

On the topic of amps and sounding good, why do people insist the power hungry planars from hifiman need to be run out of speaker taps of a speaker amp to sound better than a headphone out of a dedicated headphone amp?  One explained that it might be possibly because of their large transformers being able to swing power at a very fast rate compared to the small headphone amps.  What exactly is the science behind this?  

 

 

As for high impedance headphones not needing a powerful amp to sound better, I for the most part agree.  When I had a 600Ω Beyer, it sounded largely the same out of a 4th gen iPod touch compared to a dedicated tube amp in terms of technicalities, but the major differences were the sound signature changes brought out by the driver tubes and the louder volume.  Otherwise the iPod held its ground.  No nasty clipping, distortion or lean bass.

post #40 of 59
Quote:
Originally Posted by mikeaj View Post

I think part of the issue is a lack of volume matching when comparing.  The sequence might go something like this:

 

  1. Get headphones with high impedance
  2. Listen — and perhaps not at a satisfyingly loud volume (after all, going close to 100% can't be good, can it?)
  3. Get more powerful amp
  4. Listen again — but at an unintentionally louder volume (after all, there's so much of the volume rotation left on this shiny and powerful amp!)
  5. Things sound different and better because of the louder volume, even any differences in performance and expectation biases aside

 

Put more food on the plate, and people will eat more...

 

There's often no sense of a loudness reference, just 10% / 50% / 100% in software, and 9 o' clock / 12 o' clock on a potentiometer or other volume slider, which don't map to meaningful units when comparing different headphones.

 

This is probably the best explanation so far how more power typically ends up sounding "better".

post #41 of 59
Quote:
Originally Posted by TMRaven View Post

One explained that it might be possibly because of their large transformers being able to swing power at a very fast rate compared to the small headphone amps.  What exactly is the science behind this? 

 

Well, if the headphone amplifier has a regulated power supply, and it does not fall out of regulation while driving the HE-6 at the maximum output level, then it does not make much sense.

post #42 of 59

My question originally stems from the HE-6 vs HE-500 topic on the full-sized headphones forum.  I linked to this comparative review from Tyll, using the Apex Pinnacle, and some HE-6 fans have said that it's not being driven to the fullest of its potential because it's not being run out of speaker taps from a speaker amp.  Is there any apparent downside of that expensive Pinnacle that you see as a fault?

 

Here's the page where people were questioning the Pinnacle's ability to drive it: http://www.head-fi.org/t/591639/is-the-hifiman-he-6-clearly-a-league-above-the-hifiman-he-500/15

post #43 of 59

If you wanna listen at high SPL to non compressed music then there might be something to it. It's a very inefficient headphone, actually worse than some speakers.

 

Otherwise I think the Pinnacle should deliver enough power. What's a bit strange though is that the frequency response is down 1.5 dB at 20 kHz.

post #44 of 59

Dont know what the sonic differences are, but I  do know this - the Pinnacle costs 10K USD and I can get a (highly regarded) 40W Marantz speaker amp, brand spankers, for a little over $300. Simple arithmentic if my main aim is driving headphones which demand at least 6 clean Watts. :eek: 

 

John Atkinson had a small problem with the 'Source Direct' function on his PM5003 when he did the Stereophile measurements, but Marantz sent him another review sample and the problem went away.  

 

http://www.stereophile.com/content/marantz-pm5003-integrated-amplifier-measurements

 

http://www.stereophile.com/content/marantz-pm5003-integrated-amplifier-follow-april-2010

 

For those who see something in any of those graphs which dont look 'ideal', I guess the question is simple - is it something you would be prepared to spend $9700 to fix

post #45 of 59
Quote:
Originally Posted by estreeter View Post
For those who see something in any of those graphs which dont look 'ideal', I guess the question is simple - is it something you would be prepared to spend $9700 to fix

There are cheaper ways to downgrade. wink_face.gif

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