[leeperry]

I've compared the DT770 Premium 250Ω and 600Ω, and they were a clear night and day...much clearer trebles and much faster response. Hell, they even were much lighter when having a 250Ω driver in one hand and a 600Ω in the other(I bought the 600Ω drivers as spare parts).
 
http://europe.beyerdynamic.com/headphones-headsets/faqs.html
 
"The impedance is determined by the voice coil (dynamic headphones), which is a winded copper wire (coated to avoid a short-circuit). This copper wire is available in nearly every length, but not in every gauge (thickness) and a thicker wire has less resistance than a thin wire ("less fits through"). The magnetic field of the voice coil depends on the number of windings of the coil, causing a low impedance system to use a thicker (also heavier) wire and since the membrane foil can't be infinitely light-weight, the moving mass (voice coil and membrane) is relatively high. It's pretty clear that a higher mass can't move as easily (following an audio signal) as a lower mass. This low mass can easily be accomplished with thinner (lower weight) wire, but the thinner wire has a higher impedance. This means that the DT 770 PRO with 250 ohms sound more natural, but plays (depending on the used headphone amplifier) not as loud as the 80 ohms version."
 
being skeptic is good, but these are FACTS. And yes, my 32Ω cd3k kills all their 600Ω Manufaktur phones but that's just how BD engineer their drivers...higher impedance = faster reponse and clearer trebles, just like nikchen said: http://www.head-fi.org/forum/thread/424842/beyerdynamic-dt880-closed-back
 
"The 600ohm driver have much more precise bass and the overall sound is clearer. These are really a big step and should be preferred. Of course the result is good with the 250ohm systems but you give away potential."

 

[xnor]

When measuring 250 and 600 ohm versions you should maybe also try to measure another 250 or 600 ohm model.
Every driver is a bit different from the next one.
 
I remember measuring DC resistance and I've seen differences of ~5 ohms between left and right driver (!) on a 50 ohm headphone iirc.

 

[Catharsis]

 
Quote:

 

Ignoring your aggressive language for now, which I find distracting in an objective discussion, I don't understand your point here.
 
With regards to output impedence, doesn't the higher dampening factor on the 600ohm version make it more immune to coloration due to the headphone's non-flat impedence? That said, most amplifers don't have higher than ~120ohm out impedence (even the OTL tubes) so in this sense the 250ohm version seems good enough.
 
In addition, I am confused by your goals. Do you just want to prove there's a difference, or do you want to see an improvement? An improvement in what sense? A flatter FR?

 
My apologies for my agressive language, I'll tone it down. 
 
I'm trying to demonstrate that there is no (or very little) difference between the 250ohm and 600ohm Beyers according to objective data.  I'm hoping somebody can objectively prove me wrong. 

 

[Catharsis]

 
Quote:

With higher impedance, you get less current requirements, higher damping factor, higher signal-to-noise ratio, less crosstalk, and probably some other things I am forgetting.  Amps aren't quite perfectly linear, so I wouldn't be surprised to see different responses to different loads.  In many applications (I mean not audio in general), impedance in the low hundreds and especially in the tens is often considered unusual and difficult to deal with.  Some of the highest-fidelity line-driver op amps aren't spec'd for impedances below 600 ohms, so a more "typical" load might be better driven.  As mentioned earlier, many volume potentiometers have issues with channel balance in low settings, which a high impedance headphone would not need to be operated at.  Non-class A amplifiers have more trouble at around zero output, which happens more at a lower gain setting required by lower impedances.
 
Of course, these differences are most likely very marginal between 250/600 versions, though the 32 ohm version could be somewhat different because of these things.  Just take these as possible factors.

x2.
 
I've calculated the FQ deviation with a 51ohm Zout into a 250ohm DT880 load (using headroom impedance graphs) and there is a boost of 0.25dB @100hz.  The 600ohm DT880 would be less so but still inaudible.  The damping factor with most amps between the 250ohm and 600ohm DT880 should create inaudible differences.

 

[Catharsis]

 
Quote:

I've compared the DT770 Premium 250Ω and 600Ω, and they were a clear night and day...much clearer trebles and much faster response. Hell, they even were much lighter when having a 250Ω driver in one hand and a 600Ω in the other(I bought the 600Ω drivers as spare parts).
 
http://europe.beyerdynamic.com/headphones-headsets/faqs.html
 
"The impedance is determined by the voice coil (dynamic headphones), which is a winded copper wire (coated to avoid a short-circuit). This copper wire is available in nearly every length, but not in every gauge (thickness) and a thicker wire has less resistance than a thin wire ("less fits through"). The magnetic field of the voice coil depends on the number of windings of the coil, causing a low impedance system to use a thicker (also heavier) wire and since the membrane foil can't be infinitely light-weight, the moving mass (voice coil and membrane) is relatively high. It's pretty clear that a higher mass can't move as easily (following an audio signal) as a lower mass. This low mass can easily be accomplished with thinner (lower weight) wire, but the thinner wire has a higher impedance. This means that the DT 770 PRO with 250 ohms sound more natural, but plays (depending on the used headphone amplifier) not as loud as the 80 ohms version."
 
being skeptic is good, but these are FACTS. And yes, my 32Ω cd3k kills all their 600Ω Manufaktur phones but that's just how BD engineer their drivers...higher impedance = faster reponse and clearer trebles, just like nikchen said: http://www.head-fi.org/forum/thread/424842/beyerdynamic-dt880-closed-back
 
"The 600ohm driver have much more precise bass and the overall sound is clearer. These are really a big step and should be preferred. Of course the result is good with the 250ohm systems but you give away potential."

I've read this material over at the Beyer site before, but I've never bought into it (manufactuer marketing). The graphs over at headroom also don't seem to support Beyer's comments about impedance differences.
 
Also, you've reported subjective opinions of your headphones, and although appreciated, is not convincing.

 

[xnor]

Catharsis, trust me, you're better off ignoring people that talk about "faster response", heh.

 

[leeperry]

 

 
I've read this material over at the Beyer site before, but I've never bought into it (manufactuer marketing). The graphs over at headroom also don't seem to support Beyer's comments about impedance differences.
 
Also, you've reported subjective opinions of your headphones, and although appreciated, is not convincing.

 
nope, not only. the weight of the 250/600 drivers is also way different...but surely nikchen and I are poor victims of teh evil placebo.
 
the headroom graphs are meaningless for many reasons, but you don't trust facts or real world experiences, good luck w/ your pointless thread.

 

[ProjectDenz]

How is it pointless?

 

[leeperry]

because whatever you will tell the OP, he will stand by his meaningless headroom graphs and call ppl on bs.
 
"talking about sound is like dancing about architecture" someone said, bite the bullet...compare both, and become a believer.

 

[Catharsis]

Quote:

because whatever you will tell the OP, he will stand by his meaningless headroom graphs and call ppl on bs.
 
"talking about sound is like dancing about architecture" someone said, bite the bullet...compare both, and become a believer.

leeperry, there is far more physical evidence to contradict your subjective impressions.  Please tell me how a graph produced through accurate measurement is considered meaningless? The purpose of this thread was to challenge the superior claims made by 600ohm DT880 owners (relative to the 32ohm / 250ohm) by examining the evidence, and you haven't convinced me, and I doubt you've convinced some of the other skeptics who have joined in on this discussion.
 
I agree with factors such as "damping factor", SNR, and THR being "slightly" better in a higher impedance headphone though the results are very small and possibly inaudible. 
 
This is a sound science forum, and there is no place for subjective interpretation.  Your word about what you hear is not considered evidence. 

 

[leeperry]

 

 
Please tell me how a graph produced through accurate measurement is considered meaningless? The purpose of this thread was to challenge the superior claims made by 600ohm DT880 owners (relative to the 32ohm / 250ohm) by examining the evidence, and you haven't convinced me
[..] 
I agree with factors such as "damping factor", SNR, and THR being "slightly" better in a higher impedance headphone though the results are very small and possibly inaudible. 
[..]
Your word about what you hear is not considered evidence. 

1) let's see? first, these FR measurements are meaningless because we all hear differently: http://www.davidgriesinger.com/headphones.htm
 
"the coupling of high frequencies to the eardrum varies greatly among individuals.  It is influenced by the volume of the concha, the diameter and geometry of the ear canal, the eardrum impedance and other factors."
 
So you're showing some FR comparisons and using circular logic, calling bs on the superior sounding 600Ω...*but* who said that their FR was a night and day? Beyer never said so, they said that the voice coil was lighter and would allow for faster transients and finer details...and it does, even a blind man can see it.
 
xnor is still shining by his cluelessness because some headphones *do* provide faster transients than others...I would suggest him to go out more often on sundays and maybe compare a D2000 to an SA5000, this would clear his mind hopefully.
 
http://www.google.com/search?q=faster+transients+speakers
 
http://www.polkaudio.com/caraudio/products/6x9/speakers/mm691/
 
"Lower mass means faster transients and finer detail"
 
2) yes, the THD would most likely be lower on the 600Ω drivers.
 
3) I never said that nikchen's and my real world experiments were "evidences", I said that the 600Ω drivers were lighter than the 250Ω..meaning their voice coil is lighter and copper having a high mass, the drivers mass is different. And we call it a fact where I come from.

 

[xnor]

Talking about damping factor, many seem to forget the voice coil resistance. With a 250 ohm model it might be somewhere around 200 ohm, but with the 600 ohm model it's quite higher (maybe around 500). 
 
With superconductors the story would be a bit different, but we're not quite there yet.
 
May the EMF be with you, guys.

 

[xnor]

Quote:

1) let's see? first, these FR measurements are meaningless because we all hear differently: http://www.davidgriesinger.com/headphones.htm
<sarcasm>Oh, of course, that renders all measurements meaningless. Sigh!
 
Beyer never said so, they said that the voice coil was lighter and would allow for faster transients and finer details...and it does, even a blind man can see it.
And cryoparts say that the weakening of atomic bonds removes residual stresses and hence improves sound!
 
I would suggest him to go out more often on sundays and maybe compare a D2000 to an SA5000, this would clear his mind hopefully.
I prefer saturdays and the Sony is crap.
 
<snip>random links</snip>
 

Answers in bold.

 

[nikongod]

sorry, you didnt mention that its YOUR OPINION that sony is crap. this is not the rite forum for that.

 

[Armaegis]

All this jibjab in the science forum and no one has mentioned impedance matching yet? In simple terms, you get optimal power transfer from your amplifier when your headphone impedance matches your amp impedance. I think the recording industry design standard (don't ask me to name the agency, I don't remember) is actually 120 ohm, but no one actually goes by that.
 
Here's my take on things:
- you want optimal power transfer
- you want to operate your amp within ideal ranges (because scraping the very bottom and very top of the range typically isn't optimal, for various reasons)
- different design of drivers, voice coil, wire thickness, blah blah blah, all affects the weight and magnetic force you can create, which affects the sound that can be produced
 
If I had the knowhow to build a voicecoil myself, I would... but I don't. I did however make myself a couple impedance adapters (like the Etymotic 4P/4S adapter) in 90 and 260 ohm flavours and plugging into my Bottlehead Crack amp which is designed for high impedance cans. If I plug in a straight 32 ohm can, it's hard to control and I can barely turn the volume knob without it going too loud, but no only that it doesn't sound very good. The high range is ok, but the low end sounds all flabby and undefined. Plug in an adapter and the most noticeable effect is volume attenuation. My listenable levels are now within a comfortable 10-2 o'clock sweep and the definition has increased noticeably (I hesitate to say "significantly" since we all hear things differently), especially in the low end.
 
Now this is just my experience in adding resistance to the output line. The only effect here should be noise rejection and impedance load matching to optimize power transfer.