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With EQ, HD 600 or HD 650?

The HD650 driver is rated 500mW, the HD600 driver is rated 200mW
The drivers also have different part numbers so do differ, not only in damping (foamies under the spider).

Tonally they can be made to sound very similar.
The HD600 I measured had channel imbalance.
Haven't seen this (at least not in the lows) in HD650.
Do you know if the HD6XX driver is the HD650 or HD600 unit, rated for 500mw or 200mw? How about the HD660S2?
 
HD6XX = HD650 with different paint job and different cable.
HD600 has same chassis/magnet but different moving parts.

HD660S2 is totally different driver.
 
HD6XX = HD650 with different paint job and different cable.
HD600 has same chassis/magnet but different moving parts.

HD660S2 is totally different driver.
I meant do you know if HD660S2 driver is rated for 500mw? I see Sennhesier has dropped that info from the specs page now days.
 
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Do you mean the HD660S2 ?

I have talked to the designer a while back and they simply have not tested the point where the driver breaks.
What they told me was the driver was subjected to 100mW white noise for 24 hours and did not suffer any damage.
This is continuous power and as far as Sennheiser concerned the minimum continuous power rating.
At that point the driver produces 120dB SPL average at which time the safe exposure limit is 25 seconds... (so less than half a minute).

Now comes the more interesting part about your question.

The driver can withstand 120dB SPL for 24 hours without damage.
This is 100mW continuous.
Music is never continuous, well there are quite a few songs that have a DR of 0dB. When you listen to those you should not listen to that longer than 25 seconds at 120dB average.
Most 'normal' recordings have an average DR between 6 and 15 so in power ratio between 8 and 12 meaning the average power a driver gets to endure is about 10x lower than the peak power.
This means it could well survive an amp that can provide 1W (into 300ohm) music peaks = 130dB peakSPL which should not cause any damage (using music around DR10)
That is something you really don't want to have on your head.

In other words the continuous power rating is kind of a not so relevant number in this case and probably why Sennheiser does not publish it any more.

Put that in the light of many modern drivers (sensitive low impedance headphones) is rated between 20mW and 50mW these too will be hard to blow up with music playing loud.
I did manage to blow up those drivers with test signals though (the 30mW rated ones).



Now here's
 
@Dazerdoreal I got your points the first time, and obviously you are entitled to your own opinions. :)

Yes, we can and we should try to boost the HD600's subbass... reasonably. So I'm sharing my own slightly tweaked EQ for that purpose.

Preamp: -5.5 dB
Filter: ON LSC Fc 105 Hz Gain 5.5 dB Q 0.71
Filter: ON PK Fc 145 Hz Gain -3.8 dB Q 0.5
Filter: ON PK Fc 1330 Hz Gain -2.4 dB Q 1.3
Filter: ON PK Fc 3150 Hz Gain -3.3 dB Q 2.2
Filter: ON PK Fc 3500 Hz Gain -1.3 dB Q 4.0
Filter: ON PK Fc 5000 Hz Gain -1.5 dB Q 6.0
Filter: ON PK Fc 5850 Hz Gain -2.6 dB Q 4.5
Filter: ON PK Fc 6000 Hz Gain 3.0 dB Q 0.71
Filter: ON PK Fc 7710 Hz Gain -2.7 dB Q 4.0
Filter: ON HSC Fc 13000 Hz Gain -1.0 dB Q 0.71

GraphicEQ: 20 4.1; 42 0; 20000 0

Filter: ON LSC Fc 27 Hz Gain 4.7 dB Q 0.875

-9.6 dB exactly.

-9.6 dB means that you need a decent amp. Which I believe is the reason why Oratory decided to keep his own EQ at a more reasonable -5.5 dB, so it could be used by as may people as possible.

This small addition makes the whole thing closer to Harman in the subbass range (double-checked with REW), provided the HD 600 can handle it.
Mine can, or so say my ears. :)
 
I know Oratory's Harman EQ but it did not work out particularly well for me.
That said, you just posted a different Oratory Harman EQ as I am aware of.

This is the Harman EQ of Oratory1990 you can find on his reddit. It has different numbers:

I dont mind testing yours, though. Thank you. Maybe this is an older version?
 
Well, that's really funny! :D It looks like Oratory and me have reached the same conclusion: that the HD 600 could be pushed further without issues.

Here's the "old" Oratory preset which I had, from 2 or 3 years ago. I assumed that since the HD 600 is a very old headphone, Oratory's preset wouldn't vary over time. Apparently it has, once again! (there is an even older preset which I also have)

If you compare the "old" with the new, you'll see that the new preset is basically the "old" with more bass extension, at the expense of a -9.3 dB global gain. So, practically identical to what I just posted. I'm humbled to have reached the same conclusion as Oratory on my own :)
 

Attachments

  • Sennheiser HD600 (Harman AE-OE).pdf
    418.1 KB · Views: 22
In other words, there are at least 3 generations of Harman Oratory presets for these cans (see attached files).

Global gain went from -5.0 to -5.5 to -9.3 dB.

What's funny is that the latest generation (v3) has the lowest preference rating of them all. That's weird :oops:

v2 had the lowest deviation from Harman (0.18 dB). Which means that v2 + my additional filter should in principle have the lowest deviation from Harman of them all. Oratory tends to limit himself to 10 filters max, to make things easier for most users. But EAPO doesn't have limits, so for all of us who use it... ;)
 

Attachments

  • Sennheiser HD600 v1.pdf
    418.4 KB · Views: 21
  • Sennheiser HD600 v2.pdf
    418.1 KB · Views: 27
  • Sennheiser HD600 v3.pdf
    424.9 KB · Views: 27
In other words, there are at least 3 generations of Harman Oratory presets for these cans (see attached files).

Global gain went from -5.0 to -5.5 to -9.3 dB.

What's funny is that the latest generation (v3) has the lowest preference rating of them all. That's weird :oops:

v2 had the lowest deviation from Harman (0.18 dB). Which means that v2 + my additional filter should in principle have the lowest deviation from Harman of them all. Oratory tends to limit himself to 10 filters max, to make things easier for most users. But EAPO doesn't have limits, so for all of us who use it... ;)
About your EQ and V2 of Oratory what is the additional filter you add as I do not see it, also you use 10 filters as Oratory does right?

Moreover which of the three versions of Oratory you prefer? And as I see Oratory has added two more versions diffuse and optimum right?
1736707794587.png
 
Come on @Deckard01 , surely you can read my previous posts on this page. Spoilers 2 and 3. CLICK ON THEM. Please.

As for the versions, you have to understand that THESE ARE DIFFERENT THINGS!!!
  • All Harman presets will give approximately the same sound. Good luck with hearing differences. You can of course, but they all sound pretty much the same.
  • Optimum HiFi presets will give basically "Harman with less bass", which is good for some songs and bad for others. I have already explained that in this very topic, page 2, with curves and everything: https://www.audiosciencereview.com/...s/with-eq-hd-600-or-hd-650.16767/post-2193693 . I hope you understand what a target curve is.
  • I don't use Diffuse Field.
 
Come on @Deckard01 , surely you can read my previous posts on this page. Spoilers 2 and 3. CLICK ON THEM. Please.

As for the versions, you have to understand that THESE ARE DIFFERENT THINGS!!!
  • All Harman presets will give approximately the same sound. Good luck with hearing differences. You can of course, but they all sound pretty much the same.
  • Optimum HiFi presets will give basically "Harman with less bass", which is good for some songs and bad for others. I have already explained that in this very topic, page 2, with curves and everything: https://www.audiosciencereview.com/...s/with-eq-hd-600-or-hd-650.16767/post-2193693 . I hope you understand what a target curve is.
  • I don't use Diffuse Field.
Sorry, my mistake! I will take a look at your posts! And I thought that were talking about HD650. I am not good at EQ I now stat to check and test. Thank you and sorry!.

I have read about Oluv EQ, but can not find many infos, I do not know if you know about?
 
If you compare the "old" with the new, you'll see that the new preset is basically the "old" with more bass extension, at the expense of a -9.3 dB global gain. So, practically identical to what I just posted. I'm humbled to have reached the same conclusion as Oratory on my own :)
I did not want to claim there were issues if you push the HD 600 so far. I was aware this is not a huge deal.

The subbass distortion is a fact though. Even if it does not reach an obviously annoying degree most of the time, it can reach an amount which is potentially audible. (see here)
So if you want to buy a headphone and if you know in beforehand that you want to listen to your headphone with EQ, you can pick another headphone with lower distortion.
(And if you think this is nitpicky, you dont know what degree of distortion others nitpick about in this forum.. ^^)

Anyway, bass distortion or not, I just did not manage to make my HD 600 sound as good with EQ as other headphones with EQ. I dont know what the exact reason for this is. Without EQ it is good in comparison to most other non-EQd headphones.

I am thankful for this old Oratory1990 preset though. It is interesting to play around with it, and I might prefer it over the other, not mainly for the bass distortion. I rather think it is the slight difference in the pinna gain era (1,5-5k).

If you are curious, I EQd the crinacle measurement of the HD 600 with the old and the new version of the Oratory Harman EQ and overlaid the curves in the graph (red = old EQ, green = new EQ). This is only for comparison to see how the EQ settings change the sound.

Bildschirmfoto_2025-01-12_22-39-27.png
 
Don't worry: if I want clean 20 Hz without distortion, I always have my Nighthawk :p (which I EQ too, of course)
But the HD 600 is quite impressive when EQed.
If you don't like it it's OK. Just like some people prefer Optimum HiFi vs. Harman. Just let those who like it enjoy it. ;)
 
HD 600 & Oratory Optimum HiFi -user here. Filters 1-4 only, though.

Main point is neutral correction, without that ridiculous Harman bass -mountain, which mainly addresses HD 600´s only true weakness, that attenuated bass in NEUTRAL WAY. Also couple other (much minor) blemishes can be fixed at a same time: a little swollen upper bass/low mids and those small but audible 1.3 kHz and 3.2 kHz peaks.

I don´t recommend using those higher-frequency, high-Q petty-decibel -filters 5-10 which Oratory lists in these presets.

HD 600 (and headphones in general) begins to lose consistency between head insertions above, say, 3 kHz. Goes quite lottery to correct above that. Filters begin hit aside and miss their high-Q targets on those frequencies randomly, depending millimeter level variations between head insertions. Whole total one centimeter (1 cm) variation leading already to dual decker cardinal failure.

Result is a randomly colored HD 600 -sound, which of course sounds different... but is actually only an practical decrement of fidelity for this old but still reigning neutrality king.

HD 600 responds EQ beautifully, and is a peace of cake to EQ. Mostly thanks to it´s being the most neutral headphone on market in stock condition already, there is not much to correct i.e. chances to succeed are great.
Unlike some other zig-zag -pain in the as.. eeh.. EQ -messes, which are hopeless to EQ properly in practice. From >3 kHz -reasons told earlier.
 
without that ridiculous Harman bass -mountain
[...]
higher-frequency, high-Q petty-decibel -filters 5-10
No, no, no. Please don't judge.

People can discuss, agree and disagree, but without judgment.
You don't get to judge a target curve like Harman, that has been specifically designed according to end-user preferences (you can read about it if you want).
Actually you don't get to judge a target curve at all.
And you don't get to judge somebody like Oratory who arguably is more professional in his field than you'll ever be.

Just say you like it or you dislike it, but don't judge. :)
Thank you.
 
You don't get to judge a target curve like Harman, that has been specifically designed according to end-user preferences (you can read about it if you want).
Actually you don't get to judge a target curve at all.

Harman curve is averaged VOTING RESULT of bunch of amateurs. Subject of voting was which PLEASED them most. Also super highly dependant of HOW MUCH BASS used test material happened to contain initially.

I´m quite amateur myself too, but definitely not after pleasing etc a** licking but NEUTRAL reproduction of audio. Neutral means 1:1, honesty, fidelity to source material.

Reality does not always please. Its cold and harsh environment, quite often actually, and audio must reflect it as close as possible.

If source material contains already a lot of bass, I get listening hangover only by watching that Harmans bass mountain -joke in graph.



And you don't get to judge somebody like Oratory who arguably is more professional in his field than you'll ever be.

Just say you like it or you dislike it, but don't judge. :)
Thank you.

Most likely not, but those surgical Q >4 -filters above that Point of Inconsistency of 3 kHz are just NOT PRACTICAL. They won´t realize in practice like they show in graph. Unless phones are permanently fixed/glued in listeners head on their calibrated positions.

Put phones on next head insertion 5 millimeters differently and their filter parameters and acoustical reality won´t meet anymore.
 
The subbass distortion is a fact though. Even if it does not reach an obviously annoying degree most of the time, it can reach an amount which is potentially audible. (see here)
So if you want to buy a headphone and if you know in beforehand that you want to listen to your headphone with EQ, you can pick another headphone with lower distortion.

Good luck finding that...

Bass distortion is very difficult to hear. It´s some kind of softness in bass sounds, not similar like higher frequencies.

HD 600´s distortion performance as a whole, more practical way depicting weighted harmonic distortion, is absolute top notch. Among the very top tier on market.

On Rtings -distortion scoreboard it has banged distortion score value of 8.9 to table, leaving all but its step brother HD 650 behind (which scored the same).

Talks of HD 600´s distortion being a problem is just typical internet bullshit.

Check it out yourself.



Go find headphone with better weighted harmonic distortion score than 8.9 of HD 600 & 650.
 
I had 6xx and sent it back. When EQd to Harman curve the bass was just abysmal. Soft cottonwool something instead of bass.
 
I had 6xx and sent it back. When EQd to Harman curve the bass was just abysmal. Soft cottonwool something instead of bass.
As far as I know and check because I am user only of HD600. The 6xx is more similar to HD650, but the similarities between the 6 line models are much more than the differences.
 
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