[vid]

Your HD 540 II measure a fair bit like my HD 530, but with more treble extension. Your HD 600's a bit less bright than mine, which is probably a good thing.

 

[stratocaster]

Here is my HD530ii. It didn't have any pads, so I tried several I had lying around and strangely enough some noname velour pads performed best.
 

 

[vid]

Cool. This is my HD 530, with HM5 pads loosely mounted

 
And the HD 600

 
I use a fake ear canal in my measurement setup, which is the hump at ~3 kHz in both graphs.
 
The HD 530 II doesn't look too bad..

 

[stratocaster]

Here is my favourite so far, the modded HD540II (using some internal damping) with HM5 velour pads. The following graph shows that the modded HD540II has the same bass extension of the HD600 but the midbass hump is eliminated. Plus it definitely has more air than the HD600.
 

 

[o0CosmoMemory0o]

No prizes for guessing what I'll be doing next...
 
The tonal accuracy of a stock HD540II decimates a stock HD600. Stock HD600 has upper bass emphasis and stock HD540II does not. All IMO of course. Thanks for posting your measurements.

 

[TominJapan]

I told you so  

hd222,hd430,hd540gold,hd560 I are even more musical

hd222 look nice! How would you compare them with HD540, I think I read somewhere the Hd222 is bass-´light´, would you say so vs Hd540?

 

[daltonlanny]

I cannot understand why Stereophile ranked the HD 600 as a Class A headphone and the HD 540 II a Class D headphone before it was discontinued.
To my ears the HD 540 II is clearly superior to the HD 600 in treble extension, air, timbre, midrange smoothness, and bass smoothness.
The HD 600 sounds somewhat boomy in the bass, slightly congested, and peaky around 4K compared to the 540 II.

 

[GREQ]

Because if the HD600 appears to outclass the HD540 II by a wide margin in a published ranking, it's a sure way to boost initial sales.
Quite a few vintage headphones have recently shaken my confidence in today's high-end headphones and how much they're really worth.

 

[daltonlanny]

  Because if the HD600 appears to outclass the HD540 II by a wide margin in a published ranking, it's a sure way to boost initial sales.
Quite a few vintage headphones have recently shaken my confidence in today's high-end headphones and how much they're really worth.

I agree totally.
I also wish the two way, electrostat/dynamic concept, or two way driver concept would have been researched further, and refined further too, by AKG or someone else.
I got a pair of vintage AKG K340's yesterday, and their top end is unbelievable. Much better instrument separation, air, and top-end extension than many of todays headphones. The treble almost makes up for their other shortcomings.
They just have a lack of bass, and a somewhat screwed up midrange, but the treble is truly world class on my pair, and can give me goose bumps on certain songs.
The HD 540 II treble is up there close to the K340 as well.

 

[vid]

My K 340 had lightning-quick treble decay around 5-6 kHz. Somewhat faster than the HD 530, so I'd wager a bit faster than the HD 540 too.
 
Then again, the K 340 treble was a bit slower than on my modded Yamaha HP-50 planars (these cost, what, 20 euros used?), and actually the all-dynamic, mid-1980s DT 990 has faster decay than all of those and across the entire treble range.

 

[GREQ]

Continuing OT:
I havn't been able to put down even an AKG K140 (closed back) for 4 days straight... sure it's not the most resolving or fasted decay, but it's ridiculously fun. Plenty of PRaT, lush mids, a small but very precise soundstage with a surprising amount of instrument separation and deep thumping bass.
 
Certainly the most fun sounding out of it's siblings (141, 240 etc) and ticks SO many of my boxes for a portable headphone.
It's even comfortable o_0 (stretched out the headband a fraction to JUST stop the earpads touching/denting)

 

[o0CosmoMemory0o]

For anyone who cares about my opinion, I personally believe that a significant majority of modern "high-end"  headphones are not high fidelity at all. They are nothing more than a joke; one that is simply not funny. In fact, most people's perception of what high fidelity actually sounds like are incredibly distorted as they haven't been taught correctly or have misunderstood. I have had to wade through so much misinformative crap in order to find the truth. It's taken me about 4 years of obsession with headphones and hi-fi to finally glimpse the real truth.
 
A vast majority of today's "hi-fi", considering the science that is now available, is nothing more than a scam. The truth hurts... but there it is.

 

[vid]

Technically, the HD 540 aren't hifi if we take hifi to be an undistorted sound. The problem is, and this has been said before, by how much the HD 540 distort the sound depends on outside variables, not on whether the HD 540 are hifi or not.
 
The revelation for me was that it wasn't me who was dependent on this or that headphone being hifi, it was the existence of hifi that was dependent on me.

 

[stratocaster]

HD 560 Ovation I measurements:
 

 

 

 
Here is the effect of some 5mm felt in front of the driver:
 

 
Comparison: HD560 stock - with foam in front of the driver - HD600 stock:
 

 

[vid]

Now use good EQ to match the unmodded phones exactly to the modded response and compare the CSDs.