[zilch0md]

 
Quote:

  PM-1 measurements vs LCD-X and HE-6 : http://stereos.about.com/od/Measurements/ss/Oppo-Digital-PM-1-Headphone-Measurements.htm

 
Nice find, pfillion!  Thanks!
 
At first glance, Brent Butterworth's charts imply a disappointing treble response, but reading his analysis, it seems I have no clue how to interpret these plots!  

 

This chart shows the right-channel frequency response of three high-end planar magnetic headphones: the Oppo Digital PM-1 (blue), the $1,699 Audeze LCD-X and the $1,299 HiFiMan HE-6. All three measure practically dead flat between 50 Hz and 1.5 kHz. Above that, the PM-1 basically splits the difference between the LCD-X and the HE-6, which suggests it may be the most neutral-sounding headphone in this bunch.

 

A perfect result here would be two lines that completely overlap, which would indicate that the PM-1's tonal balance doesn't change when you change source devices. And as you can see here, the PM-1's result on this test is pretty close to perfect.

 
His analysis of other measurements indicate less than "perfect" results, but nothing alarming, in my opinion. 
 
Mike

 

[ssrock64]

Originally Posted by zilch0md /img/forum/go_quote.gif
 
In my case, this includes the Meier Audio Stepdance, the iBasso PB2 Pelican (with various combinations of op-amps), the Shiit Vali, the CEntrance DACmini CX, and the Beresford MkII (a wonderful match for PM-1).  We're not supposed to comment on the HA-1 itself, but as a comment for the PM-1, I agree with keanex and aamefford - I'm not hearing any hiss with the PM-1, there, either, despite its having gobs of power.)
 
Mike

You've mentioned the Stepdance quite a lot during your impressions. I've been considering buying a Quickstep for a new portable rig starring my HD650, and it would be great if it jived with the PM-1 and PM-2 as well. Would you mind writing a little more in detail about your experience using the PM-1 with the Stepdance?

 

[jerg]

I can't interpret those FR / CSD measurements either, it seems he posted raw plots without any compensation. The only things that can be interpreted are the major relative differences in FR between the PM1 and LCDX/HE6. Seems PM1 is smack dead in the middle in terms of upper mids / lower treble energy between LCDX and HE6. Treble-wise it's a bit confusing because the graph is so compressed, I would wait for compensated measurements from more familiar folks.

 

[musicheaven]

Here is a good site for headphones measurements, they don't have the PM-1 as part of the phone selection but most of the other ones are available.

http://www.headphone.com/learning-center/build-a-graph.php?graphID%5B0%5D=4061&graphID%5B1%5D=3431&graphID%5B2%5D=4061&graphID%5B3%5D=&scale=30&graphType=0&buttonSelection=Update+Graph

 

[jerg]

Here is a good site for headphones measurements, they don't have the PM-1 as part of the phone selection but most of the other ones are available.

http://www.headphone.com/learning-center/build-a-graph.php?graphID%5B0%5D=4061&graphID%5B1%5D=3431&graphID%5B2%5D=4061&graphID%5B3%5D=&scale=30&graphType=0&buttonSelection=Update+Graph

No, instead of that, you want to use InnerFidelity (the personal website of the same person who does these Headroom measurements, Tyll Hertsens), which has nicer plots and a bigger archive of headphones, even lots of modded headphones.
 
http://www.innerfidelity.com/headphone-data-sheet-downloads
 
That said even InnerFidelity is not my fav measurement source, in terms of how well the measurements correlate with my own ears.

 

[MattTCG]

I have no issue with the perceived, "lack of air." I'll take a euphoric, warm tilt with great mids any day over air. This is why the hd800 and he6 were not for me. 

 

[keanex]

  No, instead of that, you want to use InnerFidelity (the personal website of the same person who does these Headroom measurements, Tyll Hertsens), which has nicer plots and a bigger archive of headphones, even lots of modded headphones.
 
http://www.innerfidelity.com/headphone-data-sheet-downloads
 
That said even InnerFidelity is not my fav measurement source, in terms of how well the measurements correlate with my own ears.

 
Well graphs are graphs. Your ears might be more sensitive to certain frequencies causing the disconnect between what you hear and what you expect. This isn't odd though, if you visit Golden Ears you will see that for their graphs they include a "what we hear" vs what is measured. The key thing is to find one place that measures them all the same, which Tyll does. This allows you to compare graphs all done the same way.

 

[jerg]

   
Well graphs are graphs. Your ears might be more sensitive to certain frequencies causing the disconnect between what you hear and what you expect. This isn't odd though, if you visit Golden Ears you will see that for their graphs they include a "what we hear" vs what is measured. The key thing is to find one place that measures them all the same, which Tyll does. This allows you to compare graphs all done the same way.

What Tyll's archive is missing is spectral decay; also it's difficult for me (moreso than from other reputable measurement sources) to interpret the treble behaviour with Tyll's FR plots.
 
As for what I mean by having measurements correlate strongly to my subjective perception; I have done lots of parametric equalization with sine waves in the past with M50s...kind of like how Bigshot does things. And with those experiences I ended up with a very specific perceived M50 frequency response for my own ears. Out of all the measurement sources on the internet, only 1 source has an M50 FR plot that corresponds perfectly to my independently-generated subjective M50 FR.
 
Correct compensation is mighty important.

 

[musicheaven]

No, instead of that, you want to use InnerFidelity (the personal website of the same person who does these Headroom measurements, Tyll Hertsens), which has nicer plots and a bigger archive of headphones, even lots of modded headphones.

http://www.innerfidelity.com/headphone-data-sheet-downloads

That said even InnerFidelity is not my fav measurement source, in terms of how well the measurements correlate with my own ears.

Thanks it's always going to be science versus human perception, to me you need both to get a complete picture and understand why your perception is what it is. Tyll has it right.

 

[zilch0md]

  You've mentioned the Stepdance quite a lot during your impressions. I've been considering buying a Quickstep for a new portable rig starring my HD650, and it would be great if it jived with the PM-1 and PM-2 as well. Would you mind writing a little more in detail about your experience using the PM-1 with the Stepdance?

 
I'm a huge fan of the Stepdance, having contributed a lot of posts to that thread on the subject of increasing the power output by increasing the supply voltage.  With a modestly power-hungry headphone like the LCD-2, several people have testified on that thread that supplying maximum permissible 15VDC external power, noticeably improves the dynamics, bass control and extension of the LCD-2.  This is because the OPA1611 op-amps used by the Stepdance actually put out more power (i.e. greater swing voltages) to the headphones when supplied with 15VDC vs. the power sent to the headphones with a rechargeable 8.4V battery (9V form factor).   
 
But running the Stepdance with higher supply voltages yields increasingly less dramatic improvements when using efficient IEMs or even efficient headphones. So it's all about transducer efficiency vs. available power, and in the case of the Stepdance driving the PM-1, I can't hear any improvement by going to 15VDC vs. an 8.4V internal battery (unlike the big differences heard when doing that with the less efficient LCD-2).
 
See:  http://www.head-fi.org/t/507835/meier-audio-quickstep-also-stepdance-and-2stepdance-discussion-and-impressions-thread/2190#post_9468806
 
Off that subject, the Stepdance is wonderfully neutral and transparent - it's basically not there - a nearly perfect amplifier - and given that it has plenty of power for the PM-1, even on an 8.4V rechargeable battery, the question becomes:  What does your source do to the PM-1?
 

 
Mike

 

[Beagle]

  I have no issue with the perceived, "lack of air." I'll take a euphoric, warm tilt with great mids any day over air. This is why the hd800 and he6 were not for me.

 
Yeah, this would work better over the long term for me as well. If it's an LCD-2 sound in a lighter, more comfortable housing, I could live with it. But if the top octave is chopped off, it would eventually get to me.

 

[keanex]

I've started working on the skeleton of my review, I still need at least another week before I'm comfortable with the sound, but I can not think of one con as I write this. Perhaps I'll find something to nit-pick but I would imagine that anything that anyone could complain about with these would be minor nitpicks or preferences in a sound signature. These are a hell of a headphone.
 
I'll take my gushing elsewhere now!

 

[DairyProduce]

So how many people actually have both the 560 and the PM-1s? I see some people saying in some other threads how the 560 is superior, but from what I've read they don't actually have either headphones...

 

[Frank I]

  Frank I,
You are using them with your WA5. Do you have any noise problems?

no noise issues at all with the WA5

 

[conquerator2]

  So how many people actually have both the 560 and the PM-1s? I see some people saying in some other threads how the 560 is superior, but from what I've read they don't actually have either headphones...

Frank does, but he's waiting for the retail version of 560s.
He hasn't compared them yet but likes both.