[Solrighal]

I'm not an engineer, obviously.

 

[Katun]

That's too bad about the plug. I'm coming up on 4 years with my pair. Probably wouldn't last as long though if I actually used them on-the-go like intended.

 

[MorrisL]

So, I finally had time to sit down with my PX100 ii and HD600 for a lengthy AB test. The musical genres I chose for this test mostly centered around well-recorded classical works, including both chamber and orchestral pieces. I also used some rock music for more reference. I used my Presonus HP4 amp, going straight into my laptop, for both of them.
 
What I found was that PX100 ii is indeed a fine headphone, but the overall sound quality (all things considered) never approach that of the HD600, at least to the extent of Katun's experience.
 
Katun did say, however, that HD600 has a bigger "size" and "authority." I think that's absolutely true, too, but it's no small commentary. That "authority" makes HD600 significantly superior, not slightly. If I have both headphones on the table in front of me and I'd like to listen to say a symphonic piece, there's just no way I am going to choose PX100 ii over HD600. Absolutely no way. Even with the better comfort of PX100 ii (it's better, but not by much; it still creates itchy hotspots after a lengthy session.) On the other hand, if I had to go some place and didn't want to bother taking HD600 and the amp with me, I'd be perfectly happy with PX100 ii. It would probably be the only headphone I'd like to take with me for any short trip, even though it currently doesn't come with the very useful hard case it once came with. 
 
Besides "size" and "authority," I felt HD600 had better reproduction of sound, and was much closer to what one would expect to hear in a live performance. It was never more so apparent than with vocals. You just hear a better voice resonance with HD600. Instrument separation, sound stage, wide open air, resolution... all of these things are a lot better on HD600. No matter what music I choose to play through these, HD600 consistently gives more satisfaction. This is actually a great way to hear and appreciate HD600 for what it is - a fine full-sized headphone with unmatched reputation in its price range. And PX100 ii shines as a wonderful small, portable headphone (which is what it sounds like, too) that is likely to be better than every other headphone in its size and price range. 
 
I finished my test with a bigger appreciation for both headphones. Each of them is great for their intended use. 
 
P.S. Ironically, both have horrible cables. The sticky, rubbery, unpleasant-to-touch cable of the PX100 ii is worse than HD600's unusually thin and fragile cable (at least it's replaceable). I have dirt-cheap ($15) Sony MDR V150 headphones with cable that's much, much better than both of these. That's a shame. Good headphones like these should never come with such miserable cable design.

 

[Solrighal]

  So, I finally had time to sit down with my PX100 ii and HD600 for a lengthy AB test. The musical genres I chose for this test mostly centered around well-recorded classical works, including both chamber and orchestral pieces. I also used some rock music for more reference. I used my Presonus HP4 amp, going straight into my laptop, for both of them.
 
What I found was that PX100 ii is indeed a fine headphone, but the overall sound quality (all things considered) never approach that of the HD600, at least to the extent of Katun's experience.
 
Katun did say, however, that HD600 has a bigger "size" and "authority." I think that's absolutely true, too, but it's no small commentary. That "authority" makes HD600 significantly superior, not slightly. If I have both headphones on the table in front of me and I'd like to listen to say a symphonic piece, there's just no way I am going to choose PX100 ii over HD600. Absolutely no way. Even with the better comfort of PX100 ii (it's better, but not by much; it still creates itchy hotspots after a lengthy session.) On the other hand, if I had to go some place and didn't want to bother taking HD600 and the amp with me, I'd be perfectly happy with PX100 ii. It would probably be the only headphone I'd like to take with me for any short trip, even though it currently doesn't come with the very useful hard case it once came with. 
 
Besides "size" and "authority," I felt HD600 had better reproduction of sound, and was much closer to what one would expect to hear in a live performance. It was never more so apparent than with vocals. You just hear a better voice resonance with HD600. Instrument separation, sound stage, wide open air, resolution... all of these things are a lot better on HD600. No matter what music I choose to play through these, HD600 consistently gives more satisfaction. This is actually a great way to hear and appreciate HD600 for what it is - a fine full-sized headphone with unmatched reputation in its price range. And PX100 ii shines as a wonderful small, portable headphone (which is what it sounds like, too) that is likely to be better than every other headphone in its size and price range. 
 
I finished my test with a bigger appreciation for both headphones. Each of them is great for their intended use. 
 
P.S. Ironically, both have horrible cables. The sticky, rubbery, unpleasant-to-touch cable of the PX100 ii is worse than HD600's unusually thin and fragile cable (at least it's replaceable). I have dirt-cheap ($15) Sony MDR V150 headphones with cable that's much, much better than both of these. That's a shame. Good headphones like these should never come with such miserable cable design.

 
You need the HD 650. Better sound than both and a far better cable. Connectors are still **** though.

 

[Katun]

  So, I finally had time to sit down with my PX100 ii and HD600 for a lengthy AB test. The musical genres I chose for this test mostly centered around well-recorded classical works, including both chamber and orchestral pieces. I also used some rock music for more reference. I used my Presonus HP4 amp, going straight into my laptop, for both of them.
 
What I found was that PX100 ii is indeed a fine headphone, but the overall sound quality (all things considered) never approach that of the HD600, at least to the extent of Katun's experience.
 
Katun did say, however, that HD600 has a bigger "size" and "authority." I think that's absolutely true, too, but it's no small commentary. That "authority" makes HD600 significantly superior, not slightly. If I have both headphones on the table in front of me and I'd like to listen to say a symphonic piece, there's just no way I am going to choose PX100 ii over HD600. Absolutely no way. Even with the better comfort of PX100 ii (it's better, but not by much; it still creates itchy hotspots after a lengthy session.) On the other hand, if I had to go some place and didn't want to bother taking HD600 and the amp with me, I'd be perfectly happy with PX100 ii. It would probably be the only headphone I'd like to take with me for any short trip, even though it currently doesn't come with the very useful hard case it once came with. 
 
Besides "size" and "authority," I felt HD600 had better reproduction of sound, and was much closer to what one would expect to hear in a live performance. It was never more so apparent than with vocals. You just hear a better voice resonance with HD600. Instrument separation, sound stage, wide open air, resolution... all of these things are a lot better on HD600. No matter what music I choose to play through these, HD600 consistently gives more satisfaction. This is actually a great way to hear and appreciate HD600 for what it is - a fine full-sized headphone with unmatched reputation in its price range. And PX100 ii shines as a wonderful small, portable headphone (which is what it sounds like, too) that is likely to be better than every other headphone in its size and price range. 
 
I finished my test with a bigger appreciation for both headphones. Each of them is great for their intended use. 
 
P.S. Ironically, both have horrible cables. The sticky, rubbery, unpleasant-to-touch cable of the PX100 ii is worse than HD600's unusually thin and fragile cable (at least it's replaceable). I have dirt-cheap ($15) Sony MDR V150 headphones with cable that's much, much better than both of these. That's a shame. Good headphones like these should never come with such miserable cable design.

 
Thanks for the comparison impressions. Great to read another's take.
 
Something I just realized is that I have now owned the HD600 and HD650 five times over the past few years... each. I think I keep second guessing my judgment call of my appreciation of the PX100-II and end up repurchasing the HD600 or HD650 "just to be sure". Each and every time though, it always ends with the same outcome. I almost think it almost boils down to me not thinking they are a good enough value when compared to the PX100-II, when in fact, I think both the HD600 and HD650 are stellar values in their own right (especially with all the recent deals). If I could handle the comfort (which I'm not sure why it took me 10 purchases total to figure out I simply cannot wear them) and had a nice tube amp pairing, I think I'd be inclined to favor them over the PX100-II, whilst still being hesitant about the price differential. All of 'em sound great though!

 

[MorrisL]

   
You need the HD 650. Better sound than both and a far better cable. Connectors are still **** though.

I'll see if I can give it a nice audition at the first opportunity, even though I've kinda decided to get LCD2 as my open phone endgame. I love dark signatures and might as well move up to Audeze. 
 
The connectors are atrocious. They are so hard to remove from my HD600, that if you accidentaly pull on the wires, the wires are more likely to break than snap off. Again, unlike PX100 ii, they are at least replaceable. So, I'm not too worried about them.

 

[MorrisL]

   
Thanks for the comparison impressions. Great to read another's take.
 
Something I just realized is that I have now owned the HD600 and HD650 five times over the past few years... each. I think I keep second guessing my judgment call of my appreciation of the PX100-II and end up repurchasing the HD600 or HD650 "just to be sure". Each and every time though, it always ends with the same outcome. I almost think it almost boils down to me not thinking they are a good enough value when compared to the PX100-II, when in fact, I think both the HD600 and HD650 are stellar values in their own right (especially with all the recent deals). If I could handle the comfort (which I'm not sure why it took me 10 purchases total to figure out I simply cannot wear them) and had a nice tube amp pairing, I think I'd be inclined to favor them over the PX100-II, whilst still being hesitant about the price differential. All of 'em sound great though!

 
I don't think our impressions are all that different. You do admit (if I understood correctly) that HD600 and 650 are superior. You just feel that, given the phenomenal comfort on PX100 ii, it's a trade-off you're willing to take. That is a perfectly reasonable position. I just didn't find the PX100 ii so exceptionally comfortable and, in addition to that, I think the quality of at least HD600 is significantly better, not slightly. It's still not the night-and-day difference one would experience with HD600 and virtually any other small-sized portable headphone.

 

[Solrighal]

These aren't for me but they're interesting all the same..
 
http://www.amazon.co.uk/gp/product/B008DL1XHM/ref=pe_1980281_70574541_em_1p_4_ti

 

[keepitsimple]

To the last several posters.I really appreciate your views and have enjoyed the comparisons between the 600 and 650.The comfort issues have been noted.

 

[ElMarcado]

I can confirm that the PX-100 are is the most fun-sounding headphones i've ever listened to. They sound so tridimensional and it's incredible considering their size. They blow away the 'funnest' Grado (SR325is for some and for me) in the 'in-your-face' sound. They lack a little of impact though, and for now they can't match the SR325is SQ IME. Maybe a little more of burn-in will change that, because I remember that out-of-the-box they sounded incredibly boring and with bloated bass, and after at least 50 hours they don't sound like that anymore IMO. Right now i'd describe it's sound as a 'more tridimensional but less refined' SR325is. I hope that time will change that.
 
These are the epitome of the in-your-face, punchy fun sound, and in some recordings the soundstage can be just incredible with great imaging and width, which NONE of the Grado's i've tried can match, ever. The little treble roll-off just makes them well-balanced, not boring or veiled at all, IMO, which I cannot say about the SR325is when it puts at least 3 treble peaks of 5-10 dB to be entertaining. Very recommended for Metal and just people who love an in-your-face sound.

 

[sjbrook]

I only recently purchased my PX100/II as my 10 year old PX100's were just sort of worn out.  Pads were shot, headband padding collapsed, driver socket/ball connection breaking.  I was greatly pleased by improvements to the overall construction and the change to a single sided wire but...the sound seemed a little too murky, pads made my ears itch, high frequency response seemed rolled off and tizzy all at the same time.  So I started reading and probing the acquired wisdom of the hive.
 
I did the quarter mod on the stock pads and I was shocked at the improvement.  The dark humpy murk started to dissolve, the high end, while softly rolled off sounded much more natural.  Getting rid of the pad contact to the middle of my ears got rid of the itchiness. I then flipped them over as a reverse quarter and...well this is the way to go.  Everything exaggerated became much more coherent across the spectrum.  But the stock pads are so thin and flimsy that now there wasn't enough padding against my ear.
 
Today I received a package of HD414 pads.  Tried them straight up for argument's sake.  Even in that state they are far superior to the stock pads in comfort and transparency but they are still a little closed in.  Went straight to reverse quarter.  It is transformational.  Sound, comfort, snazzy good looks. 

  I couldn't  conceive of using them any other way.
 
These are primarily for portable use around the house or at the office playing high bit rate MP3 from an ancient Sansa E280 (rockboxed + 64GB micro sd) through  the last iteration of headroom's Total Airhead but they are getting a lion's share of time on the stereo, Anthem Pre2L, headphone jack is class A output from a quad of ECC88.  Currently rehabbing an ancient pair of 600Ohm K240 Monitors for that spot.  Never thought they might have to fight for playing time against these "lightweights".
 

 

[Solrighal]

Referenceing the OP, here's the FR graphs of both th PX 100-II and the HD 650. Remarkably close..
 

 

 
The HD 650 needs an amp though but when suitably paired (OTL valve amps are ideal) the sound is remarkable.

 

[heraldo]

Are there any rumours about an update to these headphones? I've been using PX100 and PX100 2 since around a decade, but I am getting a bit tired of spending money on new batches of headphones every time the cables break. Detachable cable or even a wireless version would be a phenomenal improvement in this department imo.

 

[keepitsimple]

  Are there any rumours about an update to these headphones? I've been using PX100 and PX100 2 since around a decade, but I am getting a bit tired of spending money on new batches of headphones every time the cables break. Detachable cable or even a wireless version would be a phenomenal improvement in this department imo.

I still have the first pair ever made-still in perfect order

 

[heraldo]

  I still have the first pair ever made-still in perfect order
 

Congratulations! Not really an answer to my question though.