[StanD]

   
Well, phase delays are certainly not desirable, but some amps have it.
 
And I would argue that while it's not desirable from an electrical standpoint, it may have a good effect mechanically, because some headphones have significant phase shifts at certain frequencies.
 
A representative would be the Sennheiser HD800... which has some crazy phase response.
 
In fact, I'd strongly suspect that the HD800's soundstage is as a result of its phase shifts more than anything else.

This is all conjecture, especially about the HD800. If we're in the context of bass, the HD800's have little phase differences. Don't confuse the phase changes in a dynamic driver vs.planar. As far as dynamic drivers I don't think the HD800's are that wild. The HD600's are considered neutral yet have a more exaggerated phase plot than the HD800's. Same story for the HD650's vs HD800's. If I remember the shape of the HD800 diaphrams are designed to deliver sound to the ears in as they call it a "natural manner." I wouldn't want to have to characterize the acoustic coupling between headphones and head/ears, sounds like a headache to me. In light of all of this, I might not want to take pot shots at guessing this out.
Phase shifts introduced by simple stereo expansion circuits while entertaining do not sound good. Audio reproduction is IMO not a sound effects application.

 

[StanD]

By the way, what did he mean by, "Capacitors don't work that way!"

I have no idea! I'm not an EE and I don't have that background. That was the the first, last and only time I've ever seen him.

We were trying to eliminate some alternator whine from this system. He couldn't comprehend that in practical use you could clean up the DC by shunting the noise (AC) to ground.

After starting the engine and noticing the lack of noise, he walked off.

Maybe he had to go and study up some more as using a capacitor in this manner is classic. Using a series inductor/choke passes DC and blocks AC/RFI/noise which works in conjunction with that capacitor for an even better result.

 

[Bill-P]

  This is all conjecture, especially about the HD800. If we're in the context of bass, the HD800's have little phase differences. Don't confuse the phase changes in a dynamic driver vs.planar. As far as dynamic drivers I don't think the HD800's are that wild. The HD600's are considered neutral yet have a more exaggerated phase plot than the HD800's. Same story for the HD650's vs HD800's. If I remember the shape of the HD800 diaphrams are designed to deliver sound to the ears in as they call it a "natural manner." I wouldn't want to have to characterize the acoustic coupling between headphones and head/ears, sounds like a headache to me. In light of all of this, I might not want to take pot shots at guessing this out.
Phase shifts introduced by simple stereo expansion circuits while entertaining do not sound good. Audio reproduction is IMO not a sound effects application.

 
Actually, I'm not sure we're looking at the same phase graphs. Are you sure the HD800 has little phase difference where bass is concerned?
 
Because Tyll Hertsen's graph is saying something else:
http://www.innerfidelity.com/images/SennheiserHD800.pdf
 
And unless I'm misinterpreting it, I don't think that phase response is "little" at all. It's in fact the same phase graph as the ones he has for the HD600 and HD650 as well.
 
And here's a dynamic headphone that has a milder phase response:
http://www.innerfidelity.com/images/BeyerdynamicDT880600ohm.pdf
 
Phase shifts introduced by certain circuits may actually rectify those wild graphs and make them more linear. In which case, I don't think it's undesirable. Unless you're suggesting that the phase shift of the headphone itself is already desirable to begin with?

 

[money4me247]

  What if they see that you already have a stand and don't want to give you their stand.

hahah rotfl!!!! that is a very artistic professional-lookin pix tho! good job

 

[Bill-P]

  Thank you for the informative response. This is the type of data I am looking for.
 
However, I know I personally cannot hear any differences below 0.1dB from my own personal testing, so i imagine there has to be something else at play here. I would definitely be interested in hearing from people who are knowledge about the other factors accounting for discrepancies in performance between adequately powered amplifier performance.

 
I think it has more to do with your scale in the context.
 
A 0.1dB signal would probably be a noticeable difference compared to a 0.5dB signal... but may not be so audible against a 80dB signal, say.
 
But beyond that, I don't think you'll get much response from others on this topic because there is a lot of parameters involved...
 
For instance, if the amplifier requires a 3-prong power connector, and you're in a country where the power plugs only have 2 prongs because the 3rd ground prong is not standardized in the power grid? And you try to disregard that 3rd-prong by connecting to an adapter?
 
You're in for a world of noise introduced in your amplifier even if it has adequate power to amplify a headphone. And that's still true even if it has a lot of headroom (a 5W amplifier driving a 32-Ohm dynamic headphone, for instance)
 
And that's just one thing that would affect the performance of an amplifier.
 
So I'd say... "adequately powered" is truly misleading in that case.
 
One would have to dig pretty deep and start looking at the schematic of an amplifier to truly know its performance characteristics beyond the nice graphs and numbers that are published.
 
But it's not ethical or even legal to reverse-engineer commercial products like that, so that's why there's not much of a discussion on this.
 
It's easier to nitpick DIY designs because the schematics are readily available, and the flaws are apparent after some calculations, but then that's like nitpicking that someone's doodles found online is not on the same level as a piece of art sold in a gallery.
 
And beyond that, there is psychoacoustics involved that would affect your mood and emotions beyond the amplifier itself.
 
I mean... not to be mean, but seriously, I think it should be said that there is a reason no one has stepped out to write something on this subject.
 
Edit:
 
Side note: I have attempted to research this subject myself... and the answer I have continuously bumped into is... there is just no answer. There are way too many possible causes that it's hard to pinpoint one, and from an electrical standpoint, there are amps that are designed to have very good performance and specifications, and yet they will sound different to other people.
 
But I have typically found that it is the case that amps with very good power supplies and not-so-good amplifying circuits (phase issues, frequency response issues, etc...) are "preferred" over amps that "do nothing wrong".

 

[StanD]

   
Actually, I'm not sure we're looking at the same phase graphs. Are you sure the HD800 has little phase difference where bass is concerned?
 
Because Tyll Hertsen's graph is saying something else:
http://www.innerfidelity.com/images/SennheiserHD800.pdf
 
And unless I'm misinterpreting it, I don't think that phase response is "little" at all. It's in fact the same phase graph as the ones he has for the HD600 and HD650 as well.
 
And here's a dynamic headphone that has a milder phase response:
http://www.innerfidelity.com/images/BeyerdynamicDT880600ohm.pdf
 
Phase shifts introduced by certain circuits may actually rectify those wild graphs and make them more linear. In which case, I don't think it's undesirable. Unless you're suggesting that the phase shift of the headphone itself is already desirable to begin with?

I think you're comparing impedance curves between the HD600 and HD800. Check the colors on the graph legends. Also set the magnification the same when comparing the graphs. You will also notice some discepancies in the markings for impedance and phase that can confuse viewing the graphs.
Trying to use an unknown phase shift on some amplifier to compensate for an phase shift that varies from one headphone to another is a shot in the dark. Headphones are very complex, it is possible that a phase shift in a headphone might play out in the design of how it is delivered acoustically to the ear. In this case both of us might be guessing and I wouldn't want to mislead others with conjecture.
I'm on the east coast so I'm throwing in the towel for today. In 2 minutes, it's tomorrow for me.

 

[money4me247]

 
I think it has more to do with your scale in the context. A 0.1dB signal would probably be a noticeable difference compared to a 0.5dB signal... but may not be so audible against a 80dB signal, say.
 
But beyond that, I don't think you'll get much response from others on this topic because there is a lot of parameters involved...
 
For instance, if the amplifier requires a 3-prong power connector, and you're in a country where the power plugs only have 2 prongs because the 3rd ground prong is not standardized in the power grid? And you try to disregard that 3rd-prong by connecting to an adapter? You're in for a world of noise introduced in your amplifier even if it has adequate power to amplify a headphone. And that's still true even if it has a lot of headroom (a 5W amplifier driving a 32-Ohm dynamic headphone, for instance) And that's just one thing that would affect the performance of an amplifier. So I'd say... "adequately powered" is truly misleading in that case.
 
One would have to dig pretty deep and start looking at the schematic of an amplifier to truly know its performance characteristics beyond the nice graphs and numbers that are published. But it's not ethical or even legal to reverse-engineer commercial products like that, so that's why there's not much of a discussion on this. It's easier to nitpick DIY designs because the schematics are readily available, and the flaws are apparent after some calculations, but then that's like nitpicking that someone's doodles found online is not on the same level as a piece of art sold in a gallery.
 
And beyond that, there is psychoacoustics involved that would affect your mood and emotions beyond the amplifier itself.
 
I mean... not to be mean, but seriously, I think it should be said that there is a reason no one has stepped out to write something on this subject.

 
I agree. The relative scale of signal differences makes a big difference in audibility. Btw, a fun blind test for seeing what kind of volume level changes you can pick out yourself for people interested: http://www.audiocheck.net/blindtests_level.php?lvl=0.1
 
Your response was very comprehensive and matches up well with what I learned from digging around. I'm sure your experience building amplifiers yourself gives you a lot better understanding of this topic than me. I have personally experienced noise issues with certain amps that may be caused by other factors beyond the actual amplifier, but it interesting how different amplifiers have varying sensitivity to noise. Wonder what design approaches are involved with that. I would be quite interested in hearing more about the common 'nitpicked' flaws are for diy designs, though I guess it probably isn't something you can pick up or explain in a few short paragraphs on these forums.
 
I agree that psychoacoustics also plays a big part in all this, though that is the confounding stuff that I am trying to separate out. hahah. very fascinating topic for sure though and I appreciate your thoughtful responses

 

[Currawong]

Before we get further derailed, please bring this back to discussion of the HE560. 

 

[Soundsgoodtome]

+1

Before we get further derailed, please bring this back to discussion of the HE560. 

 

[Bill-P]

  I think you're comparing impedance curves between the HD600 and HD800. Check the colors on the graph legends. Also set the magnification the same when comparing the graphs. You will also notice some discepancies in the markings for impedance and phase that can confuse viewing the graphs.
Trying to use an unknown phase shift on some amplifier to compensate for an phase shift that varies from one headphone to another is a shot in the dark. Headphones are very complex, it is possible that a phase shift in a headphone might play out in the design of how it is delivered acoustically to the ear. In this case both of us might be guessing and I wouldn't want to mislead others with conjecture.
I'm on the east coast so I'm throwing in the towel for today. In 2 minutes, it's tomorrow for me.

 
Well, I have scaled the graphs and matched them pixel to pixel, and that's what I observed.
 
Anyway, sleep tight! I hope we'll get to discuss this further another day!
 

  I agree. The relative scale of signal differences makes a big difference in audibility. Btw, a fun blind test for seeing what kind of volume level changes you can pick out yourself for people interested: http://www.audiocheck.net/blindtests_level.php?lvl=0.1
 
Your response was very comprehensive and matches up well with what I learned from digging around. I'm sure your experience building amplifiers yourself gives you a lot better understanding of this topic than me. I have personally experienced noise issues with certain amps that may be caused by other factors beyond the actual amplifier, but it interesting how different amplifiers have varying sensitivity to noise. Wonder what design approaches are involved with that. I would be quite interested in hearing more about the common 'nitpicked' flaws are for diy designs, though I guess it probably isn't something you can pick up or explain in a few short paragraphs on these forums.
 
I agree that psychoacoustics also plays a big part in all this, though that is the confounding stuff that I am trying to separate out. hahah. very fascinating topic for sure though and I appreciate your thoughtful responses

 
Well, most of the stuffs I mentioned would apply more for conventional dynamic drivers, though.
 
And that's what's baffling me.
 
The HE-560, and the HE-6, aren't really dynamic headphones, and... their performance characteristics are completely different.
 
Some things that greatly affect the performance of dynamic headphones won't have an effect at all on planars like the HE headphones. For instance: output impedance.
 
And yet one can still pick out the differences between amplifiers with the HE headphones.
 
I have observed that my HE-560 at least improves to every improvement I make to the stability and linearity of the power supply unit of an amp as a whole... and that's still true even when there is a lot of overhead (low volume listening or just plainly ridiculous output power), so perhaps that is one criteria to look for in an amp that can "adequately power" the HE headphones per se.
 
The other would probably be synergy.
 
And talking about which, I am really really impressed with the Yulong A28 mated with the AMB Gamma2 DAC.
 
Even though it's not a balanced DAC, the Gamma2 gives a very smooth, lush, punchy sound, and the pairing finally gives the Yulong A28 that holographic projection ability with my HE-560.
 
It almost makes me want to stop working on my DIY amp. It's just so dang good. Someone asked me if the A28 might be my end-game rig, and I'd say now... yeah, this might well be end-game. Focus Pads A + HE-560 + A28 + Gamma2 does it for me.
 
But I'll keep moving and see what would happen when I make my next prototype with a more interesting power supply design. If nothing else, it'll allow me to make an amp with a more compact body compared to the A28, which is on the big side.
 

Before we get further derailed, please bring this back to discussion of the HE560. 

 
Already did. Sorry about that! 

 

 

[Wildcatsare1]

^Hey, I am not complaining, decided its time for me to keep my yap (typing fingers) shut and see if I can learn something.

To All, apologized directly to Money, but thought I should Man up and apologize to the thread had a snickers bar (very funny commercials), I was wrong Swipers, you offering any anger management groups?

Edit: spelling

 

[jerg]

 
 

 

[ThurstonX]

 
 
 

 
Can I pre-order the hardback edition from Amazon?

  Seriously, this is gonna be good.  My HE-560s are my least modded cans... probably.  You couldn't tell from the pic I just shamelessly posted in order to get a free headphone stand 

 

[HeadphoneAddict]

  Has anyone tried the He-560 with any portable amps they have that do a decent job driving them? Currently at home I am using the Audio-gd NFB 28 and it is really growing on me, but for when I am in my bed or something I am now using the Cayin C5 with a rockboxed iPod, and it sounds fantastic for what it is. Good clarity and detail with nice impact in a bass.

 
I walked around RMAF last weekend for two and a half days, sharing my HE-560 via portable HiFi-M8 DAC/amp and lossless music on iPhone 6 with dozens of people, and not one person complained about the sound in any way. 
 
Two gentlemen from Florida shared a table with me and my son for lunch on Saturday, and I let them try the HE-560.  They went straight to the HiFiMan booth and tried to buy a pair, but Fang didn't have any for sale until the end of the day Sunday and these guys were leaving before then.  The positive responses were universal.  True, not everyone who liked them is going to actually buy them, but I'm pretty sure that I "sold" at least three HiFi-M8 and HE-560 after people tried my gear.
 
(cross posted to another forum too)

 

[swspiers]

   
Nice one.  I also have a low B and, with convincing objectivity, I can rebut all those people who say the HD800 is weak in low end.   Do you ever play through the 560 ?  How does it handle that rumble ?

I never did use the 560's that way, mostly because I had a different amp hooked-up at the time, and my Eden was packed away.
 
I can state that the Alpha Dogs are the best monitoring headphones I have ever heard. Their ability to deliver the depth and tone of my 6-string are unmatched, in my experience so far at least.