Quote: This is the impedance of the line output, not to be confused with the speaker output which should be much less than 1 Ohm.

Quote: Very interesting remark! Do you mind sharing your experience with us? Have you auditioned a number of HE-500 pairs, some older and some newer and found this? Have you, by any change, made any observation about the timing of the sound signature change?   

Quote: Yes. These are fairly sensitive dynamic phones and dacmini should be capable of driving them to maximum levels.

Quote: This translates to 0.75W driving HE-500 (38 Ohm resistance), little less than the recommended 1W but not too much. I recommend that you measure HE-500 resistance with a multimeter. HE-500 seems to have impedance that varies alot and this may lead to driver differences from HE-500...

Quote: Congrats! What are your 1st impressions? How it compares to your previous phones?

Thank you for sharing your experience with us. Your observation adds to the many others about this issue. But why you do not use the same DAC?  Now, nobody is really sure if the benefit comes because of the DAC change.

Quote: Glad you've liked it! Enjoy your modded HE-500!    Please, keep in mind that mechanical protection has been compromised.

Quote:   300Hz may indeed fail into the female vocal range, but I am not sure. The simple test that Jerg described may be the proof. Personally, I was more annoyed on some male voices and mid-bass organic sounds. It is more than 2 months now that I have modded my HE-500 completely...

Quote: +1

Quote:   Of course I do find that the HE-500 without the grills have more high frequency energy (about 2-3 db). I equalize that for most songs. Removing the grill in HE-500 is, for my ears, overall beneficent. Apart from the much better soundstage that you already mentioned, the annoying...

Quote:   It is very easy to evaluate by yourself. Temporarily remove the stock grill/mesh plate and see if you like the new sound. I, personally, much preferred my HE-500 without the grills.

Quote:   Well done for your continuous efforts! The way you describe for evaluating the effects of the grill is very interesting. One other way for easily spotting mechanical resonances only, is by connecting your headphone as a mic (just put its jack to a sound card’s mic input). While...

Quote:   I added the link to the 2nd post.   I have not any available time (and will not have for at least some months) to try and compare the sound of Jerg's mod with mine, but I suspect that there would not be much of a difference. And it sure protects much better the driver!  ...

Nice work Jerg!    I fully agree with you that the stock grill is "obstructing"  the sound, closing it and making it less 3d and clear. In HE-500 there was a noticeable increase in treble energy (2-3dB)  and I had to equalize it in most songs. Was any treble boost ih HE-400 with your mod...

Quote:     The cheapest way of making HE-500 bassier is by applying moderate amounts of equalization. Actually, this is the cheapest way for every headphone, but it is especially true for HE-500 (and most planars) due to its long dynamic range in low frequencies.   If this is not an...

Quote: Maybe you should try this and see if it helps.

Quote: You can just try the mod for a few minutes and see, eeh sorry, hear for yourself!  Personally, I have tried to put the mesh back on the other day because I wanted to re-check if I still prefer it, and reject the 'normal' sound of HE-500 in a couple of minutes. Although it is still...

Quote:   I have found (in my HE-500) that there is a nasty resonance in the mid-low frequencies that makes bass less tight than it should. This resonance comes from the back black mesh. Removing it makes bass tighter and punchier, but it adds, also, a good amount (about 2dB) of treble...

Quote: In theory, this is correct only for normal dynamic drivers, NOT orthodynamics! Orthos do not excibit the normal low fequency driver resonance that need to be damped by the high damping factor. Only normal dynamic drivers do.

Quote:   1stly, enjoy your HE-500!      I don’t know if I can imagine correctly what you describe, I have found that there is more presence in human voices in some notes because of a nasty 320Hz resonance from the black back protective mesh plate. Others haven’t complained about it...

Quote: The 1st thing we noticed was serious difference in apparent sound volume. Then I measured the resistance and after we level match them, we compared them and then we noticed the sonic quality difference. 

Quote: Very odd! Do these amplifiers warn against open (with no output load) operation? Is it normal for an amp to be destroyed when working with no load?   Maybe you are right, this is nonsense. 

Quote:   How can you say so? Have you tested your HE-500 side-by-side with one with different resistance and verified that there is no difference in sound quality? Do you know that, according to this, Fang himself, the man who designed HE-500, seems to accept +-25% resistance variations...

Quote: No, higher impedance means lower current load and better transformer operation. You do not need a resistor in parallel.   Only some digital amplifiers, that need a low pass filter in their output, may work best with lower impedance loads. Some of them may also require balance...