n4te said:

  Can you give some examples of balanced amps that would work?
 
The Schiit Wyrd seems to be USB 2.0, which I guess would make the Zoom work as 2.0 rather than 3.0 it supports. It's a little unfortunate, though I doubt it would matter much.
 
Another option is to replace the Zoom with a single device that does all that I want. I want a high quality USB DAC, high quality speaker and headphone outputs, a large volume knob on the front (not a tiny knob and not on top), a mic input, and no dancing lights. It's surprising how hard it is to find a high quality option that meets these criteria!
 
When I found the Zoom I was also looking at the Focusrite Scarlett Solo (mystery specs) or 2i2 (specs seem OK) or Steinberg UR22mkII (mystery specs, tiny volume knob) or PreSonus AudioBox iOne (mystery specs). I guess a Schiit Modi + Magni could work, though I think the Magni volume would control both the speakers and headphones.

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The Schiit Mjolnir would work.  The Cavalli Liquid Carbon would work.  However, at that point you're so wildly outclassing your Zoom that it seems silly to hook up a $600 amp to whatever the Zoom cost you.  
 
Honestly, your best bet if you need a mic input, is probably a USB mic into your computer, like the AT2020 USB or something similar.  Otherwise you're looking at spending >$1000 on something like a Grace m920 (Massdrop currently has them for $1399, which is a great deal, but certainly not cheap).  http://www.gracedesign.com/products/m920/m920.htm (actually now that I think of it, you'd actually need a Grace m905, not m920 and the m905 would likely certainly be overkill for what it seems like you want to do).

Sheesh. It seems like what I want is right in the middle of a big void in the available products. >$1000 is excessive. Around $600 might be doable if it did what I wanted perfectly. I guess I could ditch the mic input requirement and use a USB sound card for that (probably with an extension cable).
 
It's so annoying that the UAC-2 headphone amp sucks, otherwise it would be perfect.
 
Maybe the Focusrite Scarlett Solo or 2i2 is a reasonable, cheap alternative?

n4te said:

  Sheesh. It seems like what I want is right in the middle of a big void in the available products. >$1000 is excessive. Around $600 might be doable if it did what I wanted perfectly. I guess I could ditch the mic input requirement and use a USB sound card for that (probably with an extension cable).
 
It's so annoying that the UAC-2 headphone amp sucks, otherwise it would be perfect.
 
Maybe the Focusrite Scarlett Solo or 2i2 is a reasonable, cheap alternative?

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I think the Magni2Uber with a balanced dual 1/4" to unbalanced RCA cable is your best bet if you want to keep the headphone input into your single audio interface, that would essentially just push the headphone amplification and speaker pre-amplification to the magni while leaving the rest in tact on the UAC-2.  In that scenario I believe that the M2U works as a pre-amp for the speaker outs though (and thus the volume control would control the speaker out line level) and it seems like you don't want that either.
 
Yes, it's a bit of an awkward combo of wanting high-fidelity headphone output, powered speaker output with a mic input on a single USB outboard device.  I also might not be aware of some options that might work for you, as it's not a category I'm intimately familiar with.  

Well no. 
You are the one equivocating things (again)
 
Quote:

fjrabon said:

 
you're equivocating two slightly dissimilar things: combined voltage drop and damping factor.  
 
A headphone with a flat impedance curve won't "be almost unaffected by lack of damping factor."
 
Me x3: It will be almost unaffected because the Frequency Response won't change and that's the most hearable effect of low damping factor.
Even when damping factor is as low as 1, the sound won't be as blurred as people think.
I've compared my 62 Ohm AKG K702 (which by the way is significantly more resolving and critical than the headphones discussed here) with less than 1 Ohm output impedance - damping factor over 62 - vs 470 Ohm output impedance - damping factor 0.13!!!! The result was just a slight blurriness (yeah... SLIGHT). The effect was hearable during A/B but far from ruining the experience, and we are talking about damping factor = 0.13! here and we are talking about a very detailed headphone that easily expose this kind of things. *
 
 What impedance curves tell you is the power demands the headphone places on an amp, and how steady it needs its voltage supply to be over a range of impedances.  The HD650, for example, needs an amp with very little voltage drop, so it needs an amp that has relatively similar amounts of current available at its average impedance (300 ohms) and its peak impedance (500 ohms @ 100 Hz), otherwise it experiences clipped bass, which sounds wooly and lifeless.
 
Me x3: Again, no. You are always confusing voltage, current and power concepts. It's completely false that you need similar amounts of current available at its average impedance (300 Ohm) and its peak impedance (500 Ohm). That's not how Ohm's Law works. As the impedance raise, the current needed goes down. So you need significantly less current at its impedance peak compared with its average impedance.
If you really want to preserve HD650's sound signature, you need an amplifier that's able to provide the same (or VERY similar) Voltage for 500 Ohm load and 300 Ohm load (Same Voltage - Not current, Not power)
 
Clipped bass comes from a completely different phenomena that has to do with the amplifier being limited with regards to Voltage Swing. If the amplifier runs out of voltage then you'll hear clipping, which is the signal will be cutted at the higher values and thus you'll get distortion. Normally, the bass clips first because in most recordings the bass is louder than the rest of the frequencies. In this case, headphones like the V-Moda M100 are Extremely sensitive and thus you won't run out of voltage at healthy (or even slightly unhealthy loud) listening levels (even with UAC-2, even with a low grade phone)
 
 This is why Sennheiser engineers, despite the HD6XX series having relatively high impedance, say their headphones are designed for 0 ohm output impedance amps, because while damping factor isn't an issue, voltage drop is.  A headphone with a flat impedance curve, on the other hand, doesn't have this worry, and you only need to concern yourself with the amp's power delivery at a single impedance and damping factor.  The larger the amp's output impedance, the more important this becomes, as voltage drop becomes comparatively larger.  With a 0 ohm output impedance amp (practically defined as anything with output impedance of 1 ohm or less), voltage drop is stable, and the headphone performs without any voltage drop across the frequency response, ie you get the frequency response you bargained for.  Some people like the sound of some headphones with a large voltage drop because of this FR alteration, but in my experience, it almost always does more damage than good, as you're literally getting clipping in certain frequencies but not others.  
 
Me x3: I encourage you to make the math for the Sennheiser HD650 with 1 Ohm output impedance and 30 Ohm output impedance so you can put this in perspective.
What you'll get is a difference in the mid-bass that's well under 0.5dB !
 
Damping factor, on the other hand, has to do with a headphone's ability to "bounce back" against the impedance of the source, and thus deliver quick, dynamic performance.  Under-damped headphones sound the opposite of punchy, instead sounding much more "slushy."  Now, yes, some people prefer under-damped headphones, because it can cause the bass to be very boomy, with longer decay, while some headphones can sound overly dry and analytical if they're properly damped.  On some headphones it's not particularly a big deal.  My Shure SRH840, for example, can take output impedances a good bit above its recommended 6 ohms and sound fine.  But my THX00 starts to sound wooly with any amp over 1 ohm, even though it should be okay with anything up to 4 ohms.  
 
Me x3: Pretty much the same as *
I don't have the THX00 impedance plot in mind, but that might play a role here.
Damping factor is not the only variable when it comes to amplifier's sound signature.
I guess you are not trying the same amplifier with 1 Ohm and 4 Ohm, so the difference could be somewhere else (not damping factor related).
It would be interesting to do an ABX with the THX00 and the 1 Ohm amplifier switching back and forth between a ~0 Ohm cable and a 4 Ohm cable
 
Also, for the OP, the Zoom is one of the worst headphone amps people pay money for.  It's got the double downside of being high output impedance *and* underpowered.  Honestly it will probably sound worse than simply playing out of your phone.  That isn't to say it can't sound okay in certain scenarios, but to be blunt, it's a piece of junk.  Literally the only things you really need a headphone amp to do is provide enough power with a low enough output impedance to allow your headphones to shine.  The Zoom fails in both of those regards.  Its high output impedance means that you get a large voltage drop and insufficient damping.  This will render your headphones comparatively lifeless in comparison to an amp with more appropriate specifications.  I hate to be blunt, but you really shouldn't worry about spending money on good headphones if you're using the Zoom.
 
That being said, the UAC-2 is a good DAC.  I think of it as a DAC that has an emergency amp built in.

Click to expand...

me x3 said:

Me x3: It will be almost unaffected because the Frequency Response won't change and that's the most hearable effect of low damping factor.
Even when damping factor is as low as 1, the sound won't be as blurred as people think.
I've compared my 62 Ohm AKG K702 (which by the way is significantly more resolving and critical than the headphones discussed here) with less than 1 Ohm output impedance - damping factor over 62 - vs 470 Ohm output impedance - damping factor 0.13!!!! The result was just a slight blurriness (yeah... SLIGHT). The effect was hearable during A/B but far from ruining the experience, and we are talking about damping factor = 0.13! here and we are talking about a very detailed headphone that easily expose this kind of things. *

Click to expand...

you're confusing damping factor with voltage drop.  I agree with the effects you describe, but you're simply calling two different things the same thing. Damping factor simply isn't a frequency response effect.  Flat impedance curve has nothing to do with damping factor, that's just not what the term is defined as.  Again, I agree that the frequency response effects are more important, but they're not the same as damping factor.  Damping factor has to do with transient response ability and decay, not frequency response stability. We often put the two factors together because the same guideline (1/8 rule) fixes them both, but they aren't the same thing.  A headphone with a completely flat impedance curve can still have damping issues that slow down/muddy up its transient response.  Maybe you don't believe this is a big deal, but if it's not, what exactly do you think actually matters when it comes to headphone amps?  Obviously the OP is not satisfied with the sound that his amp is providing, but you're essentially telling him "no, you're hearing wrong, it's plenty good enough."
 

  Me x3: Again, no. You are always confusing voltage, current and power concepts. It's completely false that you need similar amounts of current available at its average impedance (300 Ohm) and its peak impedance (500 Ohm). That's not how Ohm's Law works. As the impedance raise, the current needed goes down. So you need significantly less current at its impedance peak compared with its average impedance.
If you really want to preserve HD650's sound signature, you need an amplifier that's able to provide the same (or VERY similar) Voltage for 500 Ohm load and 300 Ohm load (Same Voltage - Not current, Not power)

Click to expand...

yes, you're right, my mistake, I inexplicably wrote current once in the middle of talking about voltage drop when I meant to write voltage.  Good catch, I will edit the original to make my response clearer, and am putting this here so as to not make it look like I said it correctly the first time.  But yes, I agree that to maintain target frequency response it needs a stable voltage supply, which 0 ohm amps are better at.  Again, maybe the effect is subtle, but that's hi-fi audio in general, that last little subtle piece.  if we only cared about getting 95% of the way, we'd all just be using stock apple earbuds out of an iPhone.

fjrabon said:

  you're confusing damping factor with voltage drop.  I agree with the effects you describe, but you're simply calling two different things the same thing. Damping factor simply isn't a frequency response effect.  Flat impedance curve has nothing to do with damping factor, that's just not what the term is defined as.  Again, I agree that the frequency response effects are more important, but they're not the same as damping factor.  Damping factor has to do with transient response ability and decay, not frequency response stability. We often put the two factors together because the same guideline (1/8 rule) fixes them both, but they aren't the same thing.  A headphone with a completely flat impedance curve can still have damping issues that slow down/muddy up its transient response.  Maybe you don't believe this is a big deal, but if it's not, what exactly do you think actually matters when it comes to headphone amps?  Obviously the OP is not satisfied with the sound that his amp is providing, but you're essentially telling him "no, you're hearing wrong, it's plenty good enough."
 
yes, you're right, my mistake, I inexplicably wrote current once in the middle of talking about voltage drop when I meant to write voltage.  Good catch, I will edit the original to make my response clearer, and am putting this here so as to not make it look like I said it correctly the first time.  But yes, I agree that to maintain target frequency response it needs a stable voltage supply, which 0 ohm amps are better at.  Again, maybe the effect is subtle, but that's hi-fi audio in general, that last little subtle piece.  if we only cared about getting 95% of the way, we'd all just be using stock apple earbuds out of an iPhone.

Click to expand...

 
Far from telling him that he's hearing wrong, I said that according to UAC-2's specs, the amplifier is definitely weak to drive the quite hungry Beyerdynamic DT770 80 Ohm, and thus I suggested a variety of much more sensitive headphones with a bassy sound signature.
 
Tyll Hertsens

The ratio of the load's impedance to the amp's output impedance is called the "damping factor."

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Source: here
 
That's what damping factor means to me.
 
What I've said, is that the MAIN and most hearable effect of having a low damping factor is the equalization in the shape of the impedance vs frequency plot.
That's the main effect.
 
Damping Factor is strongly bounded with what you call Voltage Drop, since higher the Damping Factor means lower the Voltage Drop.
 
Here's an example:
 
Let's consider the Beyerdynamic DT880 250 Ohm
+
The Beyerdynamic A20 (output impedance 100 Ohm)
 
The ratio of the load's impedance to the amp's output impedance is pretty low (Low Damping Factor)
 
Let's say we have 1V at the Beyerdynamic A20
 
In the midrange DT880/250 is a 250 Ohm load.
So you have:
1V for the 100 Ohm amplifier impedance + the 250 Ohm headphone.
 
Then:
 
350 Ohm .................... 1V
250 Ohm .................... 0.71V
 
In the Mid-Bass DT880/250 is a 300 Ohm load
So you have:
1V for the 100 Ohm amplifier impedance + the 300 Ohm headphone.
 
Then:
 
400 Ohm .................... 1V
300 Ohm .................... 0.75V
 
In both cases you can see a Voltage Drop, but that's not a problem at all as far as you don't need more voltage than the amplifier can provide.
 
What's important here is that the amplifier won't be perfectly flat (0.75V at the mid-bass vs 0.71V at the midrange)
 
------
 
Ok, let's swap the DT880 250 Ohm version for a DT880 600 Ohm version
 
Now "the ratio of the load's impedance to the amp's output impedance" is higher (OK Damping Factor)
 
Let's say again that we have 1V at the Beyerdynamic A20
 
In the midrange DT880/600 is a 600 Ohm load.
So you have:
1V for the 100 Ohm amplifier impedance + the 600 Ohm headphone.
 
Then:
 
700 Ohm .................... 1V
600 Ohm .................... 0.86V
 
In the Mid-Bass DT880/600 is a 700 Ohm load
So you have:
1V for the 100 Ohm amplifier impedance + the 700 Ohm headphone.
 
Then:
 
800 Ohm .................... 1V
700 Ohm .................... 0.87V
 
There's still a Voltage Drop here in both cases (you don't get 1V at the headphone) but again, this is not a problem as far as you don't need more voltage than the amplifier can provide.
What's important here is that the amplifier is now almost perfectly flat (0.87V at the mid-bass and 0.86V at the midrange)
 
Here we can see how a higher Damping Factor determines how flat the amplifier is when driving a dynamic driver with an impedance that varies with frequency.
 
--------------------------------------------------------------------
 
Now we can consider the V-Moda M100 and the UAC-2
 
The V-Moda is always 35 Ohm 
The UAC-2 output impedance is 33Ohm but let's say it's 35 to make this even simpler.
 
Let's say that we have 1V at the UAC-2
So we have 1V for the 35 Ohm output impedance + the 35 Ohm V-Moda
 
Then:
70 Ohm ................... 1V
35 Ohm ................... 0.5V
 
So you'll get 0.5V at the headphone and this is applicable to the whole spectrum since V-Moda M100's impedance doesn't vary with frequency.
Then the amplifier is able to provide a flat frequency response to the headphone.
 
Here's a 0.5V Voltage Drop, but again, this doesn't matter since the remaining Voltage is more than enough to drive the very sensitive V-Moda.
 
So you'll hear the M100 as it is, no added coloration. 
You'll have the rest of the effects of low damping factor, sure (not uber-ultimate transparency) but this effects are really really subtle with a damping factor equals to 1.

me x3 said:

Far from telling him that he's hearing wrong, I said that according to UAC-2's specs, the amplifier is definitely weak to drive the quite hungry Beyerdynamic DT770 80 Ohm, and thus I suggested a variety of much more sensitive headphones with a bassy sound signature.

Source: here

That's what damping factor means to me.

What I've said, is that the MAIN and most hearable effect of having a low damping factor is the equalization in the shape of the impedance vs frequency plot.
That's the main effect.

Damping Factor is strongly bounded with what you call Voltage Drop, since higher the Damping Factor means lower the Voltage Drop.

Here's an example:

Let's consider the Beyerdynamic DT880 250 Ohm
+
The Beyerdynamic A20 (output impedance 100 Ohm)

The ratio of the load's impedance to the amp's output impedance is pretty low (Low Damping Factor)

Let's say we have 1V at the Beyerdynamic A20

In the midrange DT880/250 is a 250 Ohm load.
So you have:
1V for the 100 Ohm amplifier impedance + the 250 Ohm headphone.

Then:

350 Ohm .................... 1V
250 Ohm .................... 0.71V

In the Mid-Bass DT880/250 is a 300 Ohm load
So you have:
1V for the 100 Ohm amplifier impedance + the 300 Ohm headphone.

Then:

400 Ohm .................... 1V
300 Ohm .................... 0.75V

In both cases you can see a Voltage Drop, but that's not a problem at all as far as you don't need more voltage than the amplifier can provide.

What's important here is that the amplifier won't be perfectly flat (0.75V at the mid-bass vs 0.71V at the midrange)

------

Ok, let's swap the DT880 250 Ohm version for a DT880 600 Ohm version

Now "the ratio of the load's impedance to the amp's output impedance" is higher (OK Damping Factor)

Let's say again that we have 1V at the Beyerdynamic A20

In the midrange DT880/600 is a 600 Ohm load.
So you have:
1V for the 100 Ohm amplifier impedance + the 600 Ohm headphone.

Then:

700 Ohm .................... 1V
600 Ohm .................... 0.86V

In the Mid-Bass DT880/600 is a 700 Ohm load
So you have:
1V for the 100 Ohm amplifier impedance + the 700 Ohm headphone.

Then:

800 Ohm .................... 1V
700 Ohm .................... 0.87V

There's still a Voltage Drop here in both cases (you don't get 1V at the headphone) but again, this is not a problem as far as you don't need more voltage than the amplifier can provide.
What's important here is that the amplifier is now almost perfectly flat (0.87V at the mid-bass and 0.86V at the midrange)

Here we can see how a higher Damping Factor determines how flat the amplifier is when driving a dynamic driver with an impedance that varies with frequency.

--------------------------------------------------------------------

Now we can consider the V-Moda M100 and the UAC-2

The V-Moda is always 35 Ohm 
The UAC-2 output impedance is 33Ohm but let's say it's 35 to make this even simpler.

Let's say that we have 1V at the UAC-2
So we have 1V for the 35 Ohm output impedance + the 35 Ohm V-Moda

Then:
70 Ohm ................... 1V
35 Ohm ................... 0.5V

So you'll get 0.5V at the headphone and this is applicable to the whole spectrum since V-Moda M100's impedance doesn't vary with frequency.
Then the amplifier is able to provide a flat frequency response to the headphone.

Here's a 0.5V Voltage Drop, but again, this doesn't matter since the remaining Voltage is more than enough to drive the very sensitive V-Moda.

So you'll hear the M100 as it is, no added coloration. 
You'll have the rest of the effects of low damping factor, sure (not uber-ultimate transparency) but this effects are really really subtle with a damping factor equals to 1.

Click to expand...

Damping is a well understood term and it simply doesn't have anything to do with frequency response. Yes, a large damping factor will fix voltage drop issues as well, but you can lack damping with a headphone with a flat impedance curve, which was my original point. Flat impedance curve headphones can have flabby bass, not due to frequency response effects, but rather due to not being fast enough, due to lack of damping. All the stuff you rambled on about doesnt in any way address that you're conflating two things that, while related, aren't the same thing. It's simply incorrect to say that having a flat impedance curve means damping doesn't matter like you did, for the very reason that you're talking about voltage drop, not damping. Tyll is describing how to calculate damping factor, not what damping factor sounds like when you quoted him. NWAVguy also explains the two concepts in his blog on the subject as well. This isn't at all controversial.

fjrabon said:

Damping is a well understood term and it simply doesn't have anything to do with frequency response. Yes, a large damping factor will fix voltage drop issues as well, but you can lack damping with a headphone with a flat impedance curve, which was my original point. Flat impedance curve headphones can have flabby bass, not due to frequency response effects, but rather due to not being fast enough, due to lack of damping. All the stuff you rambled on about doesnt in any way address that you're conflating two things that, while related, aren't the same thing. It's simply incorrect to say that having a flat impedance curve means damping doesn't matter like you did, for the very reason that you're talking about voltage drop, not damping. Tyll is describing how to calculate damping factor, not what damping factor sounds like when you quoted him. NWAVguy also explains the two concepts in his blog on the subject as well. This isn't at all controversial.

Click to expand...

 
I seriously doubt whether you understood/read what I wrote or not.
 
What I say, (again and again) is that the MAIN, audible effect of plugging a headphone into an amplifier that provides a low Damping Factor, is the equalization in the shape of the impedance of the headphone.
 
What's that hard to understand about that simple measurable fact?
 
More so, I've wrote 3 examples with math that exposes this behavior.
Same kind of examples you'll find on Innerfidelity.
Same kind of examples you'll probably find on NorthwestAV's Blog
Same math, same voltage divider model, same everything.
 
Is up to you to undestand it or not. 
That's the main effect of Low Damping factor (Low ratio of the load's impedance to the amp's output impedance)
 
I've NEVER said that's the ONLY effect of low damping factor. 
I've said that's the main, main, main, audible effect.
 
And I've said that other effects are normally VERY subtle. So subtle that my K702 was still nice even when plugged into an amplifier with 470 Ohm output impedance (which by the way means Damping Factor equals 0.13 !!!!!!!). The effect was subtle, apparent when doing critical A/B but subtle and that's an extreme case since the Damping Factor there was 9 times lower than the cases we are discussing here.
 
Tyll said what Damping Factor is, that's what I've quoted.
 
Feel free to continue arguing or questioning until you understand, but I encourage you to think in more objective terms.
I'm not here inventing a single thing. I'm just applying extremely simple math to an extremely simple case of electromagnetism problem.
 
If you have the means to show mathematically or in terms of measurements, what's the magnitude of Low Damping Factor's impact in sound quality besides the EQ in the shape of the impedance, please do it.
(Just as I've done with my point: "Low Damping Factor implies EQ in the shape of the impedance") 
I'm really interested.
 
But if you keep repeating what it's supposed to be, without a quantitative knowledge about the matter, then your words are useless.
 
It's very easy to write "flat response and flabby bass" but it's not that easy to explain what that really means.
Not fast enough? What happens with higher frequencies when the driver has to move faster?
Can we see the flabby thing reflected in the harmonic distortion? How does the flabby thing vary with SPL?
Do you have any measurement to back up what you say?
 
I'll make my effort to find (or encourage someone with the appropiate equipment to develop) a quatitative take to the topic
"Low Damping Factor's impact in sound quality besides the EQ in the shape of the impedance"
 
In other words, mesurability of sound quality variation caused by low damping factor in a headphone with flat impedance.

From Michael Grace of Grace designs: "The damping factor is an amplfier's ability to damp the back emf (electro motive force) from the headphone transducers. In essence this is the ability of the amplfier to control the diaphragm motion of the headphone driver and keep it from overshooting and ringing."

Again I understand the voltage drop effects you're discussing and I fully agree with your analysis of voltage drop effects. They're not the same thing as electronic damping. Overshoot and ringing aren't frequency response effects, but rather time domain effects. This is what electronic damping refers to. Further consider that there is also mechanical damping, which is a way of physically reducing a driver's ringing and overshoot. Obviously this wouldn't have anything to do with voltage.

fjrabon said:

From Michael Grace of Grace designs: "The damping factor is an amplfier's ability to damp the back emf (electro motive force) from the headphone transducers. In essence this is the ability of the amplfier to control the diaphragm motion of the headphone driver and keep it from overshooting and ringing."

Again I understand the voltage drop effects you're discussing. They're not damping factor. Overshoot and ringing aren't frequency response effects, but rather time domain effects.

Click to expand...

 
You are still quoting people giving a qualitative justification, not a quantitative one.
Qualitative explanations are extremely tricky because they say nothing about how much the described phenomena affects the measurements and more important the perceived sound, which is by the way, the only thing that matters.
 
Those selling 1000 dollar cables can easily explain in qualitative terms why the purest cable means the purest sound quality, but they always refuse to give a quantitative justification.
What's the impact in terms of measured performance? Are the effects audible/more enjoyable?
 
Michael Grace defined damping factor in a slightly different way than Tyll, although both definitions are strongly related.
I tend to prefer Tyll's more practical/mathematical definition since it's compatible with the everyday use of the Damping Factor concept included "The Rule" discussed earlier in this thread.

me x3 said:

You are still quoting people giving a qualitative justification, not a quantitative one.
Qualitative explanations are extremely tricky because they say nothing about how much the described phenomena affects the measurements and more important the perceived sound, which is by the way, the only thing that matters.

Those selling 1000 dollar cables can easily explain in qualitative terms why the purest cable means the purest sound quality, but they always refuse to give a quantitative justification.
What's the impact in terms of measured performance? Are the effects audible/more enjoyable?

Michael Grace defined damping factor in a slightly different way than Tyll, although both definitions are strongly related.
I tend to prefer Tyll's more practical/mathematical definition since it's compatible with the everyday use of the Damping Factor concept included "The Rule" discussed earlier in this thread.

Click to expand...

What you're missing here is Tyll was simply describing how to calculate damping factor, not what damping actually is. Michael Grace actually described what damping is. They don't disagree at all, and saying you prefer one over the other doesn't even make sense. That's like saying you prefer ohms law over a definition of impedance. Tyll didn't give a definition, so it can't be in conflict with Michael.

The vast majority of the time that distinction doesn't matter. However, it does matter in explicitly the situation you originally brought up, when a headphone has a flat impedance curve. Because in such case, as you've repeatedly shown, and I agree with, in that scenario there aren't impedance curve frequency response effects (normally called voltage drop when the distinction between voltage drop and damping is important). When a headphone has a flat impedance curve it can still have issues with overshooting and ringing. Any of Tyll's impulse response graphs will show you that virtually every headphone has varying levels of both of those issues. A low impedance amp will help those issues, just like mechanical damping in the driver cup will (usually in the form of bass venting and/or dynamat).

I'd like to give you a quantitative graph, but such sites showing the effect on the amp end simply don't exist at this point. Tyll may eventually get there, he's starting to finally flesh out an amp measurement page, but people simply aren't doing very many impulse response graphs of specific headphone and amp pairings. I can't give you calculations showing the effect because it's a combination of electrical properties (the amp's output impedance) and the headphone's physical design.

Now you can question whether or not overshoot and ringing are real effects all you want, and you're right that there's unfortunately precious little proof amps can help alleviate the issue, but that's what damping means, reducing overshoot and ringing in the time domain. As much is literally implied by the very term "damping" i.e. Acting like a shock absorber to produce a smoother shock/impulse response instead of the overshoot and subsequent ringing that is the norm to varying degrees.

fjrabon said:

What you're missing here is Tyll was simply describing how to calculate damping factor, not what damping actually is. Michael Grace actually described what damping is. They don't disagree at all, and saying you prefer one over the other doesn't even make sense. That's like saying you prefer ohms law over a definition of impedance. Tyll didn't give a definition, so it can't be in conflict with Michael.

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Me x3: Tyll gave a definition. Period.
 
I prefer Tyll's mathematical definition, to Michael's qualitative one.
 
It's like saying the Gravitational Force is "an attractive force between two bodies in the Universe"
That's not useful.
 
On the other hand you can define Gravitational Force as:
F = G . m1 . m2 / (r^2)
And that's a much more useful definition.
 
None of them are wrong or contradictory, but one is precise and quantifiable, the other isn't.

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The vast majority of the time that distinction doesn't matter. However, it does matter in explicitly the situation you originally brought up, when a headphone has a flat impedance curve. Because in such case, as you've repeatedly shown, and I agree with, in that scenario there aren't impedance curve frequency response effects (normally called voltage drop when the distinction between voltage drop and damping is important). When a headphone has a flat impedance curve it can still have issues with overshooting and ringing. Any of Tyll's impulse response graphs will show you that virtually every headphone has varying levels of both of those issues. A low impedance amp will help those issues, just like mechanical damping in the driver cup will (usually in the form of bass venting and/or dynamat).

I'd like to give you a quantitative graph, but such sites showing the effect on the amp end simply don't exist at this point. Tyll may eventually get there, he's starting to finally flesh out an amp measurement page, but people simply aren't doing very many impulse response graphs of specific headphone and amp pairings. I can't give you calculations showing the effect because it's a combination of electrical properties (the amp's output impedance) and the headphone's physical design.

Now you can question whether or not overshoot and ringing are real effects all you want, and you're right that there's unfortunately precious little proof amps can help alleviate the issue, but that's what damping means, reducing overshoot and ringing in the time domain. As much is literally implied by the very term "damping" i.e. Acting like a shock absorber to produce a smoother shock/impulse response instead of the overshoot and subsequent ringing that is the norm to varying degrees.

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I know what damping means, and I understand CEMF since physics is almost half of my life, but I've also experienced extreme cases like the cited above (K702 with 470 Ohm output impedance) and the sound was still nice, clear and defined. Not exactly as defined as driven with 1 Ohm amplifier, but still well defined. So I do have an idea of the magnitude of this effects to the overall sound quality.
 
As I said before, I'm really interested in further investigation, measurements of an LCD-2 driven with a 100 Ohm amplifier or something like that.
 
You seem to believe that low damping factor (read DF= 1,2,3,4) has a very noticeable impact in the overall perceived sound quality in headphones with flat impedance.
I refuse to believe that because:
1- There's no objective proof
2- It does not correlate with my experience (K702 sounded good plugged into the 470 Ohm amp)

Very interesting stuff guys. Kudos for keeping it civil -- this is unheard of the internet! Up is down, white is black. We need some angry guys to burst into the thread and restore the balance by telling everyone why they're so ******* wrong.
 
Has anyone else tried A-B'ing low damping like Me x3 has done? I wonder if the K702 has physical properties that make it more resilient for that particular test. At any rate, while I don't have a low output impedance amp, I'll be able to at least report on the V-Moda M-100 versus the Beyer DT770 using the Zoom. Unfortunately it'll be a while because I ordered the M-100 to the US so I can pick it up when I make the trip from Croatia in mid-March. I'll be back end of March with the report!
 
Today I tried a Rode VXLR 3.5mm to XLR adapter to use a 3.5mm mic with my Zoom UAC-2. Naturally, given my luck with all this crap, it didn't work at all. If I turn the gain all the way up I see -48db, without the mic plugged in. With the mic plugged in I also get -48db, though if I flick the mic the next line lights (-36db). Any ideas? The Zoom has 1/4" / XLR combo ports and the manual says to plug in a mic using XLR, but I tried with a 1/4" jack to 3.5mm adapter anyway -- nothing. I tried with 3 different (2 cheap and 1 ModMic) 3.5mm mics.
 
Assuming the V-Moda M-100 and the Zoom are good enough for my needs, the Zoom still manages to let me down by not supporting a 3.5mm mic. I use this often for VOIP and gaming. The M100 has a boom mic that uses a 4 pole plug and comes with a splitter that gives me 3.5mm jacks for mic and audio. I'll use a 3.5mm to 1/4" adapter into the Zoom (sits under my monitor) and then I'll need a 3.5mm extension cable to run the mic over to the PC into a USB sound card.
 
I wonder if there is some other electronics I should pick up in the states? If there were a replacement for the Zoom perfect for me I'd replace it in a heartbeat.

As promised, I'm back from the US with my V-Moda M-100 headphones. They are very nice! They look cool, I got the black/red "shadow" version with red aluminum covers on the ear pieces.
 
The folding and carrying case is nice, though I don't plan to travel with these since I prefer the Bose QC25's noise cancelling for that.
 
I got the "XL memory cushions" and I agree with most reviews that they are necessary. They are comfortable and I don't have problems wearing them for long periods. My wife says the QC25s are slightly more comfortable and I agree, but only slightly more. I have worn the M-100s for 4 hours without issues.
 
I got the boom mic for when I need that and it works well. I do think the shaft bends a bit too easily, any bump and it needs to be readjusted to be at the side of my mouth. The jack where it connects to the headset allows the mic to rotate away from your mouth. This is OK, eg when eating or otherwise not using the mic, but like the shaft it means any bump and the mic is no longer placed correctly. The mic has a clip which is nice to reduce noise from the cable being brushed against clothing and also removes any weight or pull of the cabling from the headphones.
 
The headphones have a 4 pole mini jack which is nice for mobile devices but otherwise a bit of a pain. It does come with a splitter so you get separate audio and mic jacks, but I've found one of my own splitters seems to work better.
 
So how does it sound! Flipping great! It's exactly what I wanted bass-wise and everything I play is sounding fantastic. The Zoom seems to be able to push it just fine, I use around half volume. If I'm losing out on any quality because of the Zoom, I can't tell and that is all the really matters to me.
 
I'm almost out of the woods, but not quite. From my M-100 splitter I take audio into the Zoom and the mic goes to an extension cable then to my onboard sound. I do this because my RealTek onboard has noise suppression which I like to clean up the mic input. The Asus Xonar Essence STX II 7.1 I tried didn't have it, and the mic input was much worse for it. Anyway, this is all fine except when the extension cable is connected, I get a buzz in my speakers. This buzz corresponds to GPU usage, exactly like the buzz I was getting before I switched to balanced cables. It happens even if the M-100s aren't connected. As long as the Zoom and RealTek are connected through the splitter, I get the buzz. I've ordered a tiny USB sound card that has noise suppression, so I'll see how that goes.
 
TL;DR, the V-Moda M-100s are great! Thank you for the suggestion!