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Sennheiser HD 660S2

Fregly

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Really interested in that trough compared to the others in the 6 series relatively even there, how audible, how it colors, for those who took the plunge. Looks like a fatal flaw, but perhaps it is not that bad. The price is brutal in Canada, I mean, the graph looks almost the same as the 58x for 150usd.
 

Limopard

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@Resolve posted measurements from the headphones.com 5128 rig along with some brief written impressions:

View attachment 264970

Compared to an HD600 with fresh pads:

View attachment 264971

As someone looking to consolidate their over-ear headphone collection, I was hoping for a super HD560S, not a darker HD650/HD6XX.
Thanks a lot. I was intrigued, but looking at these measurements I won't consider the 660s2 any longer. The first incarnation already was too dark for my taste. I stay with my HD 600.
 

Roen

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Cable is not boomy or rather microphonic, very silent, relatively flexible and light as well. Especially compared to the thick chungus you get with the HD800S.

6.3mm vs 4.4 Pentaconn jack doesn’t really matter all that much. 4.4mm is supposedly the future however there’s still a lack of amps that have it.

4.4mm is balanced which theoretically rejects electromagnetic interference better and can deliver a bit more juice as well so less gain is needed. All in all rather insignificant.
I don't think balanced headphone cables reject interference, but balanced connection between DAC and Amp does.
 

unpluggged

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I don't think balanced headphone cables reject interference, but balanced connection between DAC and Amp does.
It's not the cable that rejects interference but the differential amplifier on the receiving side of the balanced line. Which obviously does not exist in passive headphones.

In fact, "balanced headphone" is a misnomer. More correct term is differential (or, rather, bridged) amplification.
 

unpluggged

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@unpluggged headphone drivers are differential in nature. They don't react to common-mode noise.
Yes, I was implying that from the headphone's perspective there is no difference between single-ended and "balanced" amplification.
 

ugur38

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RTings measured this: https://www.rtings.com/headphones/reviews/sennheiser/hd-660s2

HD 6 Series Comparison by Rtings Measurements.png
 
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phoenixsong

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I just listened to it today and was severely disappointed, especially taking its price into consideration. Its bass sounds bloomy and although the treble isn't very fleshed out, mids still manage to sound recessed somehow
 

solderdude

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I was pleasantly surprised about the sound quality.
At first listen it did not 'stand out' like some Harman bass headphones or say hifiman with their 'hyper detail' do. In fact it sounds 'plain' and unremarkable.
It is the 'not remarkable' aspect that turns out to the remarkable thing about this headphone.
Switching to a headphone with more clarity (say HD600/650) indeed shows the (somewhat) reduced clarity. Also lacks in bass extension and stereo imaging also is not remarkable nor better than other HD6** headphones.
It does, however, create a fatigue free and pleasant listen to me. After a while I was totally comfortable with the sound.
Won't beat my HD800 (EQ'ed) though and is not as well extended in the bass and does not have the clarity of the S5X.
I do not hear bloomy bass though. Can't be a seal thing either so must be a preference thing. Female voices are lacking ultimate clarity on direct comparison but after a while I do not notice it (am not bothered by it) but enjoy the presentation.
 
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xeizo

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I have the S2, and HD600 and HD560S and NDH-30 and DT900 ProX and DT1990 and HE400SE and a lot more of cans, I wouldn't say the S2 is disappointing but you wont be immediately impressed as it's very neutral however it grows with longer listening sessions and at least myself do not get fatigue from them. I am a musician and I would say they sound a lot like music such as when I play instruments myself, certainly "HiFi".
 

solderdude

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yep, don't give it a quick listen in a store. It won't impress like some other headphones do. Give it some time and throw all kinds of music at it.
 

isostasy

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I was pleasantly surprised about the sound quality.
At first listen it did not 'stand out' like some Harman bass headphones or say hifiman with their 'hyper detail' do. In fact it sounds 'plain' and unremarkable.
It is the 'not remarkable' aspect that turns out to the remarkable thing about this headphone.
Switching to a headphone with more clarity (say HD600/650) indeed shows the (somewhat) reduced clarity. Also lacks in bass extension and stereo imaging also is not remarkable nor better than other HD6** headphones.
It does, however, create a fatigue free and pleasant listen to me. After a while I was totally comfortable with the sound.
Won't beat my HD800 (EQ'ed) though and is not as well extended in the bass and does not have the clarity of the S5X.
I do not hear bloomy bass though. Can't be a seal thing either so must be a preference thing. Female voices are lacking ultimate clarity on direct comparison but after a while I do not notice it (am not bothered by it) but enjoy the presentation.
What about the existence of the HD58x? They look so close, your measurement almost looks like it could be the L and R channels of the same headphone!! You say the HD660S2 is 'is technically better and more refined sounding', how much is in it?
 

solderdude

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Compared directly, My HD58X is modified to have lower bass response and thus is very similar to S2 in all aspects, shows that the HD660S2 sounds slightly 'more pleasant' to me. Just a bit more 'refined' in the treble. To be the HD650 has better treble quality than orig HD660S and (modified) HD58X but the HD660S2 is just slightly better.
Don't have the original HD660S though so cannot compare directly but could compare to the same HD58X I still have and had at the same time.
To give you an idea how my HD58X is below my modified + 6kHz passive filtered HD58X (which is not the same as stock HD58X) v.s. HD660S2
660S2 vs mod HD58x.png

Below stock HD58X (Romania produced) and HD660S2 do sound different and to me (may not be so for others) and HD660S2 wins.
hd58X rom.png


NOT looking at the price difference though.
I can't look into the wallet of others nor say whether or not the (small) increase/difference in SQ is worth it to someone.
The extra € 400.- one has to pay for the HD660S2 thus may not be worth it to most people but could be for someone that appreciates the difference.
Would I trade-in my modified HD58X for a HD660S2 ? Nope as I already have a HD800 which is 'better' in aspects I value the most.
Do I think the HD660S2 is worth € 600.- ? Not to me. Do I think it sounds really good ? Yes.

While I got the FR pretty much the same on FR plots in ideal circumstances and pinna-less there still are differences in the actual drivers.
This is evident when looking at the seal measurements (the HD660S2 reacts much better) due to differences in damping scheme.
Not only impedance (and thus reaction to say the HP output of an AVR) but also damping, resonance frequency and possibly even modal break-up differences in the membrane that could, certainly with many different pinnae, result in audible differences IRL situations.
So similar in FR (modified HD58X) but not the same.
 
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phoenixsong

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yep, don't give it a quick listen in a store. It won't impress like some other headphones do. Give it some time and throw all kinds of music at it.
True, I might have been hasty in my assessment. The store provided me with an iFi Diablo to drive it with, and after looking up measurements on it, it may have been the lack of transparency of the Diablo under certain conditions that causes the perceived "bloom" in sound instead of the fault of the 660S2
 
OP
Takanaka

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Despite having elevated treble and bass, almost v-shape like tuning compared to the NDH 30, I do admit it does sound very pleasant. I hope Oratory has an EQ for it soon.
 

staticV3

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Despite having elevated treble and bass, almost v-shape like tuning compared to the NDH 30, I do admit it does sound very pleasant.
What headphone has v-shape like tuning compared to the NDH-30?
 

solderdude

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xeizo

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S2 is not V-shaped compared to NDH-30 as NDH-30 has a more powerful bass that digs deeper, but the S2 is a tad more pronounced in the upper registers but which probably has more to do with the NDH-30 having a much more forward voice register midrange. It's super easy to follow singing work on the NDH-30 like the easiest ever.

Both cans sounds great in their own way and yes DT990 IS V-shaped but also has superior slam and toe tapping qualities which makes it possible to partly ignore the wonky FR or just EQ it away
 

bloodshoteyed

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first listen atm of writing, blasting JMJ's Live at Notre Dame binaural mix....i think my HP journey might be over for the foreseable future :eek:


SarcamOn/ i forgot to burn'em in tho :rolleyes: /SarcasmOff
 
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