DT880 600ohm BS - Page 12  

I agree with xnor. 

"quality" of a driver is a fairly ambiguous term, and how that "quality" translates to measured sound changes is what we're after.  Donald North did a great job of illustrating these differences with a level matched comparison (among other awesome contributors to this thread - thanks everyone).

Quote:

Originally Posted by chinesekiwi 

Quote:

I'm more saying the quality of the driver in a mechanical sense. In dynamic transducer systems, the companies can tweak the FR to whatever they like so really using the FR to judge the the differences between the quality of the driver in a mechanical sense by itself is flawed. 

I don't think that they can really tweak a transducer to any FQ response they like (within reason).  If so it would be easy to produce a totally flat FQ response, which is physically impossible from what i understand.  I don't know which variables you would use to establish driver "quality".  From what we've learned in this thread, only the length / number of windings of the voice coil wire is different between the 250ohm and 600ohm (and 32ohm) drivers.  If that's the only variable that's different, there isn't much of a change in "quality" so to speak.  All other aspects of the drivers are the same.

I think Trysaeder was implying what I'm trying to state - that the DT880 drivers are identical with the exception of different quantities of wire around the voice coil which increases or decreases electrical impedance.  The HD800 and HD555 use DIFFERENT drivers, and so they will sound different and measure considerably different across many variables which I suppose could be translated as "quality" differences.

Quote:

Originally Posted by Donald North 

When level matched, the two versions measure nearly identical in the bass and midrange but diverge in the top two octaves. At some frequencies there's a 5dB difference with the 250 ohm version generally having more treble energy (dotted yellow curve below). Depending on music spectrum and hearing acuity, such differences are easily noticeable. However I don't see one version being obviously superior to the other. To me it's personal preference.

 

Correct me if I'm wrong, but it appears as though the 250ohm version has a bit more of a 6,000hz spike than the 600ohm, BUT actually has slightly better treble extension whereas the 600ohm is less peaky (smooth) but actually rolls off slightly in the high frequencies relative to the 250ohm.  I agree with you Donald North, the 600ohm looks a TAD more "Sennheiser HD600" to me which may explain some people's preference for it.

AHA!

Headroom FINALLY has measurements of all 3 DT880 impedance variations. They don't seem to QUITE jive with the findings of Donald North but measurements seem to ALWAYS have some level of deviation even with repeated measurements.  Here you'll find a GREATER spike with the 600ohm in the 6-7000hz region (relative to 250ohm) in addition to the least treble extension of all 3.  A matter of preference I'd say.

The evidence is stacking up, and I will (sort-of) eat my words on this.  THERE IS a sonic difference between the 250ohm and 600ohm (and 32ohm) versions, albeit marginal at best assuming these measurements are accurate and not simply measurement errors / fluctuations.  Wild claims about the superiority of the 600ohm version may be chalked up to these subtle differences, or just a tad of expectation bias from the "audiophile" DT880 600ohm.

Quote:

Originally Posted by skeptic 

Just wanted to take a second shot at asking this question.  Can anyone clarify as to whether the measured differences in FR would or would not possibly translate to differences in treble timbre?

Sure it would.  FR changes would create a change in timbre, though it's difficult to qualitatively describe how timbre will change (for me).  Presumably, a peakier treble and/or better treble extension would highlight the high frequency "tings" and "pangs" of percussive and acoustic instruments, and really bring the "screech" of violin strings forward among many other things.  Treble spikes and treble extension gives a much more forward presentation to the nuances of musical timbre (a.k.a. detail) as opposed to the rolled off or smooth treble which give musical timbre a more laid back sound such as in the Sennheiser range.

If you think about how some headphones make instruments sound "hollow" or "honky", such effects are normally always a product of FR.

In fact, if you account for experimental error / measurement deviation, there is actually LESS of a difference between all 3 DT880 impedance options than the K701/K702 (same headphone, different colour), and the MDR-7506/MDR-V6 (same headphone, different colour, different plug, longer warranty). 

Observe:

Now the DT880 600ohm superiority over the 32ohm and 250ohm is even less astonishing from an objective POV.

ANSWERS IN BOLD

Quote:

Originally Posted by upstateguy 

This is not what Donald North thought.  The graphs look so close, why do you feel the 600 ohm is superior?

 

I don't think the 600ohm is superior, nor inferior, nor different at all really.  I may have worded my post incoherently - my apologies.  The original intention of my thread was to propose the hypothesis that the 250ohm and 600ohm (and 32ohm essentially) are the same headphone with the only difference being electrical impedance and therefore sound the same when objectively measured.

 

Also,  how do you account for the difference in the graphs between the 701 and 702? 

 

Same way I account for the discrepancies between the MDR-V6 and MDR-7506...measurement error.  It's not unusual to produce variations between measurements even when measuring the same headphone.  It is widely agreed upon that the K701 and K702 only differ in colour and detachable cable, and the 7506 and v6 differ in plug coating, and colour stickers.  I used these 2 examples to show the level of measurement variation as a control to contrast against the 3 impedance versions of the DT880.

 

Stereophile has a great article about headphone measurements including the difficulty in producing identical measurements of the SAME headphone when measuring multiple times. 

 

http://www.stereophile.com/features/808head/index3.html

 

Here is an example of repeated measurements on the EXACT same headphone in the Stereophile article:

 

 

USG