[erics75]

Looking forward to your observations....YMMV depending on the seal and amplification but the HD820 for me are a big step up from the HD660S2 overall, just more of everything, space, imaging, scale, bass, sub bass........the S2 almost come across 2 dimensional in direct comparison.

i'm excited to get it. i had one quite awhile ago now and it did not work for me, BUT.... my system was not really optimized for high ohm drivers like my current setup is now. i think this time around it's going to be a very different story. i can't wait to try! so much of the fun IMO is trying all the new stuff out there.

if you put aside technical prowess and just focused on the emotional connection each set brings you when listening, how would you rate/compare the S2 and 820?

 

[Rob80b]

if you put aside technical prowess and just focused on the emotional connection each set brings you when listening, how would you rate/compare the S2 and 820?

Tricky question...lol...the S2 ,relatively speaking, is a more in the the head intimate presentation which many may prefer....the HD820 like the Hd800/S are more at arms length, but not always.
Myself, being primarily a speaker person, I prefer the at arms length. : ) Is that an emotional connection, hey this is an emotional hobby, but many new headfiers may never have experienced a proper visceral stereo speaker set up, so it could infact sound alien or disconnected, wrong, the HD820 gives me more of an out of head experience but it's still a completely different listening experience. : )

 

[MattTCG]

After spending an audition period with the 660s2 and being a long time 650 owner, I thought I’d chime in with a few thoughts and comparisons. I won’t waste any time regurgitating the basics regarding build quality, cables, specs etc as those have been hashed out plenty by now. All of my findings are in comparison to the 650 unless otherwise noted.

At the initial listen the first impression that pops out at me is that there is in fact a splash more bass response with the 660s2. To be more accurate, to my somewhat educated ears, the improved bass response seems to be approximately 2db (possibly 3db) more than I’m used to with my trusty 650. Of course, one of the most popular complaints with 650 owners is that lack of (sub) bass and the associated impact that goes with it. Let me note here that most popular music is NOT recorded with sub bass frequencies. However, electronic music is more prone to use actual sub bass response in the frequency range at around 30hz or lower. I like to use the album “Unit” by Scann-Tec to test true sub bass response. The second track on this impressive EDM offering is particularly good at getting down to 30hz with good impact and remaining texturally intact. While the 660s2 does outperform the 650 with bass response on this track, it’s only by a modest margin. I’ve heard many superior efforts by other headphones at producing this track that way that the bass was meant to be experienced. For example, the ETHER 2 by DCA delivers the bass response in this track impressively and somewhat shockingly when compared to the 660s2. Comparatively, the 650 relies more on the infamous “mid-bass hump” to achieve is sonic signature. For me, this works outs wonderfully because I don’t listen to a lot of EDM music anyway and the mid bass hump gives a richer slightly warmer sound to the music I prefer.

Truth be told, 650 owners typically don’t buy this headphone for its impressive bass response, as a planar magnetic offering will almost always have a clear advantage in that capacity. We 650 lovers buy the 650 for the magical midrange. And we’re willing to accept “decent” bass and “smooth” treble as part of the package. Moving on, the treble is in fact “cleaner” and more extended on the 660s2. Has Sennheiser fixed the second shortcoming on my almost perfect 650? Well, sort of. Female vocal tracks that peek into the lower treble range do come across more airy and revealing with the 660s2 if not a little nasally and not quite as natural as on the 650. I will concede that classical music, particularly when an orchestra is led by a violinist, offers better clarity and resolution on the 660s2. In fact, classical music in general plays out better on the 660s2. To be fair Sennheiser has already created the ultimate classical headphone with hd800/800s.

For most of us, given the capacious offerings of 6x0 interations it will often come down to preferences. Some will prefer the 650 to the 600. And now some will opt for the 660s2 over the 650/600. I appreciate the effort Sennheiser has made with the 660s2. But for me and my preferences, it doesn’t quite hit the mark and will not oust the 650 as my favorite in the lineup. If you’ve ever been a musician or been around live music a lot, natural tone will always sit at the top of your list when listening to music with headphones.

Regarding amping. I do most of my testing on the THX789. It’s a fairly neutral amp without much coloring to the signature. When I switched over to the Valhalla 2 and more so when switching to the Bottlehead Crack, the 650 easily pulled ahead of the 660s2. For me, it came down to the ability of the 650 to capture and captivate with those rich, natural vocals causing me to be captivated by the music. While 660s2 did improve on both tube amps, it simply didn’t seem to “scale” as well as the 650. Perhaps on different/more expensive tube amps the results would be different.


660s2 Pros:

*nice looking (best in the lineup)

*design and build are tried and true

*good attempt to improve the sonics in the 6x0 series

*improved dynamics and staging


660s2 Cons:

*doesn’t match the ability to “scale” as well as the 650 or match the 650 “tonality”

*packaging is disappointing at this price

*ultimately does not dethrone the king

Final Edit:

After my review I put the s2 away and listed them for sale. Since they were boxed up for shipping, they were no longer being listened to or reviewed. When I didn’t get an offer on them, I decided to pull them back out and give them another listen. But this time was a little different. I wasn’t listening critically or comparatively against my 650. Also, I decided to listen to the s2 exclusively for several days. And then, something odd happened. I honestly began to really enjoy them. That splash of extra bass and touch of sparkle at the top began to grow on me. I thought to myself, “man, these are actually quite good.” Over the course of the next 5-6 listening sessions with my favorite albums I found myself at the end of the session thinking that the was the most I’d EVER enjoyed listening to that album! That is significant for me. These are recordings that I’ve listened to a hundred times with tons of headphones.

So do I rank them higher than I did originally? Did the extra break in time benefit the sound or did my brain break in with time? And finally, do I rank them better against my 650 than I did originally? At the end of the day, I do think that they are better than I judged them originally. If I’m honest, I probably do suffer from a bit of a love affair with my 650. The s2 is a very good headphone and deserves to be on the short list for anyone looking at the 6x0 series.

 

[Shane D]

After spending an audition period with the 660s2 and being a long time 650 owner, I thought I’d chime in with a few thoughts and comparisons. I won’t waste any time regurgitating the basics regarding build quality, cables, specs etc as those have been hashed out plenty by now. All of my findings are in comparison to the 650 unless otherwise noted.

At the initial listen the first impression that pops out at me is that there is in fact a splash more bass response with the 660s2. To be more accurate, to my somewhat educated ears, the improved bass response seems to be approximately 2db (possibly 3db) more than I’m used to with my trusty 650. Of course, one of the most popular complaints with 650 owners is that lack of (sub) bass and the associated impact that goes with it. Let me note here that most popular music is NOT recorded with sub bass frequencies. However, electronic music is more prone to use actual sub bass response in the frequency range at around 30hz or lower. I like to use the album “Unit” by Scann-Tec to test true sub bass response. The second track on this impressive EDM offering is particularly good at getting down to 30hz with good impact and remaining texturally intact. While the 660s2 does outperform the 650 with bass response on this track, it’s only by a modest margin. I’ve heard many superior efforts by other headphones at producing this track that way that the bass was meant to be experienced. For example, the ETHER 2 by DCA delivers the bass response in this track impressively and somewhat shockingly when compared to the 660s2. Comparatively, the 650 relies more on the infamous “mid-bass hump” to achieve is sonic signature. For me, this works outs wonderfully because I don’t listen to a lot of EDM music anyway and the mid bass hump gives a richer slightly warmer sound to the music I prefer.

Truth be told, 650 owners typically don’t buy this headphone for its impressive bass response, as a planar magnetic offering will almost always have a clear advantage in that capacity. We 650 lovers buy the 650 for the magical midrange. And we’re willing to accept “decent” bass and “smooth” treble as part of the package. Moving on, the treble is in fact “cleaner” and more extended on the 660s2. Has Sennheiser fixed the second shortcoming on my almost perfect 650? Well, sort of. Female vocal tracks that peek into the lower treble range do come across more airy and revealing with the 660s2 if not a little nasally and not quite as natural as on the 650. I will concede that classical music, particularly when an orchestra is led by a violinist, offers better clarity and resolution on the 660s2. In fact, classical music in general plays out better on the 660s2. To be fair Sennheiser has already created the ultimate classical headphone with hd800/800s.

For most of us, given the capacious offerings of 6x0 interations it will often come down to preferences. Some will prefer the 650 to the 600. And now some will opt for the 660s2 over the 650/600. I appreciate the effort Sennheiser has made with the 660s2. But for me and my preferences, it doesn’t quite hit the mark and will not oust the 650 as my favorite in the lineup. If you’ve ever been a musician or been around live music a lot, natural tone will always sit at the top of your list when listening to music with headphones.

Regarding amping. I do most of my testing on the THX789. It’s a fairly neutral amp without much coloring to the signature. When I switched over to the Valhalla 2 and more so when switching to the Bottlehead Crack, the 650 easily pulled ahead of the 660s2. For me, it came down to the ability of the 650 to capture and captivate with those rich, natural vocals causing me to be captivated by the music. While 660s2 did improve on both tube amps, it simply didn’t seem to “scale” as well as the 650. Perhaps on different/more expensive tube amps the results would be different.


660s2 Pros:

*nice looking (best in the lineup)

*design and build are tried and true

*good attempt to improve the sonics in the 6x0 series

*improved dynamics and staging


660s2 Cons:

*doesn’t match the ability to “scale” as well as the 650 or match the 650 “tonality”

*packaging is disappointing at this price

*ultimately does not dethrone the king

Final Edit:

After my review I put the s2 away and listed them for sale. Since they were boxed up for shipping, they were no longer being listened to or reviewed. When I didn’t get an offer on them, I decided to pull them back out and give them another listen. But this time was a little different. I wasn’t listening critically or comparatively against my 650. Also, I decided to listen to the s2 exclusively for several days. And then, something odd happened. I honestly began to really enjoy them. That splash of extra bass and touch of sparkle at the top began to grow on me. I thought to myself, “man, these are actually quite good.” Over the course of the next 5-6 listening sessions with my favorite albums I found myself at the end of the session thinking that the was the most I’d EVER enjoyed listening to that album! That is significant for me. These are recordings that I’ve listened to a hundred times with tons of headphones.

So do I rank them higher than I did originally? Did the extra break in time benefit the sound or did my brain break in with time? And finally, do I rank them better against my 650 than I did originally? At the end of the day, I do think that they are better than I judged them originally. If I’m honest, I probably do suffer from a bit of a love affair with my 650. The s2 is a very good headphone and deserves to be on the short list for anyone looking at the 6x0 series.

They have really grown on me. I have gone through many Sennheiser's and ended up moving all of them along.
The S2's did not impress me at all, at first. Coming off a week with the OG Clear's, they were a big disappointment. But I kept listening and after a day or two I adjusted to the sound signature.
I had another disappointing encounter after running my other favourite headphone, the Grado GH2's. But again within a day, I was won over.

Their last run started off strong and only got stronger. Playing golden oldies pop/rock, they were wonderful on my Little Dot MK9 and Valhalla 2. This is my first Sennheiser that started off rocky, but is really growing on me. And I actually find the bass more than adequate. Not Focal type bass, but better than my Grado's.

I am hoping that in a few weeks when they come up in the rotation next, that I am enjoying them even more. A nice surprise so far.

 

[erics75]

After spending an audition period with the 660s2 and being a long time 650 owner, I thought I’d chime in with a few thoughts and comparisons. I won’t waste any time regurgitating the basics regarding build quality, cables, specs etc as those have been hashed out plenty by now. All of my findings are in comparison to the 650 unless otherwise noted.

At the initial listen the first impression that pops out at me is that there is in fact a splash more bass response with the 660s2. To be more accurate, to my somewhat educated ears, the improved bass response seems to be approximately 2db (possibly 3db) more than I’m used to with my trusty 650. Of course, one of the most popular complaints with 650 owners is that lack of (sub) bass and the associated impact that goes with it. Let me note here that most popular music is NOT recorded with sub bass frequencies. However, electronic music is more prone to use actual sub bass response in the frequency range at around 30hz or lower. I like to use the album “Unit” by Scann-Tec to test true sub bass response. The second track on this impressive EDM offering is particularly good at getting down to 30hz with good impact and remaining texturally intact. While the 660s2 does outperform the 650 with bass response on this track, it’s only by a modest margin. I’ve heard many superior efforts by other headphones at producing this track that way that the bass was meant to be experienced. For example, the ETHER 2 by DCA delivers the bass response in this track impressively and somewhat shockingly when compared to the 660s2. Comparatively, the 650 relies more on the infamous “mid-bass hump” to achieve is sonic signature. For me, this works outs wonderfully because I don’t listen to a lot of EDM music anyway and the mid bass hump gives a richer slightly warmer sound to the music I prefer.

Truth be told, 650 owners typically don’t buy this headphone for its impressive bass response, as a planar magnetic offering will almost always have a clear advantage in that capacity. We 650 lovers buy the 650 for the magical midrange. And we’re willing to accept “decent” bass and “smooth” treble as part of the package. Moving on, the treble is in fact “cleaner” and more extended on the 660s2. Has Sennheiser fixed the second shortcoming on my almost perfect 650? Well, sort of. Female vocal tracks that peek into the lower treble range do come across more airy and revealing with the 660s2 if not a little nasally and not quite as natural as on the 650. I will concede that classical music, particularly when an orchestra is led by a violinist, offers better clarity and resolution on the 660s2. In fact, classical music in general plays out better on the 660s2. To be fair Sennheiser has already created the ultimate classical headphone with hd800/800s.

For most of us, given the capacious offerings of 6x0 interations it will often come down to preferences. Some will prefer the 650 to the 600. And now some will opt for the 660s2 over the 650/600. I appreciate the effort Sennheiser has made with the 660s2. But for me and my preferences, it doesn’t quite hit the mark and will not oust the 650 as my favorite in the lineup. If you’ve ever been a musician or been around live music a lot, natural tone will always sit at the top of your list when listening to music with headphones.

Regarding amping. I do most of my testing on the THX789. It’s a fairly neutral amp without much coloring to the signature. When I switched over to the Valhalla 2 and more so when switching to the Bottlehead Crack, the 650 easily pulled ahead of the 660s2. For me, it came down to the ability of the 650 to capture and captivate with those rich, natural vocals causing me to be captivated by the music. While 660s2 did improve on both tube amps, it simply didn’t seem to “scale” as well as the 650. Perhaps on different/more expensive tube amps the results would be different.


660s2 Pros:

*nice looking (best in the lineup)

*design and build are tried and true

*good attempt to improve the sonics in the 6x0 series

*improved dynamics and staging


660s2 Cons:

*doesn’t match the ability to “scale” as well as the 650 or match the 650 “tonality”

*packaging is disappointing at this price

*ultimately does not dethrone the king

Final Edit:

After my review I put the s2 away and listed them for sale. Since they were boxed up for shipping, they were no longer being listened to or reviewed. When I didn’t get an offer on them, I decided to pull them back out and give them another listen. But this time was a little different. I wasn’t listening critically or comparatively against my 650. Also, I decided to listen to the s2 exclusively for several days. And then, something odd happened. I honestly began to really enjoy them. That splash of extra bass and touch of sparkle at the top began to grow on me. I thought to myself, “man, these are actually quite good.” Over the course of the next 5-6 listening sessions with my favorite albums I found myself at the end of the session thinking that the was the most I’d EVER enjoyed listening to that album! That is significant for me. These are recordings that I’ve listened to a hundred times with tons of headphones.

So do I rank them higher than I did originally? Did the extra break in time benefit the sound or did my brain break in with time? And finally, do I rank them better against my 650 than I did originally? At the end of the day, I do think that they are better than I judged them originally. If I’m honest, I probably do suffer from a bit of a love affair with my 650. The s2 is a very good headphone and deserves to be on the short list for anyone looking at the 6x0 series.

Great writeup! I'm a huge 650 lover as well so I know the love affair thing quite well. And similar to your journey, when I was evaluating the S2 against the 650 and other headphones, it competed quite well, but I often still gravitated towards the other sets. But when I stopped comparing and just listened, I found the S2 to be one of the most enjoyable listens in my lineup. It's a nice marriage of the classic easy listening 600/650 of yesteryear and more modern headphones in terms of speed, extension, and resolution.

 

[Rob80b]

But for me and my preferences, it doesn’t quite hit the mark and will not oust the 650 as my favorite in the lineup.

Totally understandable.

And then, something odd happened. I honestly began to really enjoy them. That splash of extra bass and touch of sparkle at the top began to grow on me. I thought to myself, “man, these are actually quite good.” Over the course of the next 5-6 listening sessions with my favorite albums I found myself at the end of the session thinking that the was the most I’d EVER enjoyed listening to that album! That is significant for me. These are recordings that I’ve listened to a hundred times with tons of headphones.

but...funny how that happens. : )

 

[PlanarBunny]

After spending an audition period with the 660s2 and being a long time 650 owner, I thought I’d chime in with a few thoughts and comparisons. I won’t waste any time regurgitating the basics regarding build quality, cables, specs etc as those have been hashed out plenty by now. All of my findings are in comparison to the 650 unless otherwise noted.

At the initial listen the first impression that pops out at me is that there is in fact a splash more bass response with the 660s2. To be more accurate, to my somewhat educated ears, the improved bass response seems to be approximately 2db (possibly 3db) more than I’m used to with my trusty 650. Of course, one of the most popular complaints with 650 owners is that lack of (sub) bass and the associated impact that goes with it. Let me note here that most popular music is NOT recorded with sub bass frequencies. However, electronic music is more prone to use actual sub bass response in the frequency range at around 30hz or lower. I like to use the album “Unit” by Scann-Tec to test true sub bass response. The second track on this impressive EDM offering is particularly good at getting down to 30hz with good impact and remaining texturally intact. While the 660s2 does outperform the 650 with bass response on this track, it’s only by a modest margin. I’ve heard many superior efforts by other headphones at producing this track that way that the bass was meant to be experienced. For example, the ETHER 2 by DCA delivers the bass response in this track impressively and somewhat shockingly when compared to the 660s2. Comparatively, the 650 relies more on the infamous “mid-bass hump” to achieve is sonic signature. For me, this works outs wonderfully because I don’t listen to a lot of EDM music anyway and the mid bass hump gives a richer slightly warmer sound to the music I prefer.

Truth be told, 650 owners typically don’t buy this headphone for its impressive bass response, as a planar magnetic offering will almost always have a clear advantage in that capacity. We 650 lovers buy the 650 for the magical midrange. And we’re willing to accept “decent” bass and “smooth” treble as part of the package. Moving on, the treble is in fact “cleaner” and more extended on the 660s2. Has Sennheiser fixed the second shortcoming on my almost perfect 650? Well, sort of. Female vocal tracks that peek into the lower treble range do come across more airy and revealing with the 660s2 if not a little nasally and not quite as natural as on the 650. I will concede that classical music, particularly when an orchestra is led by a violinist, offers better clarity and resolution on the 660s2. In fact, classical music in general plays out better on the 660s2. To be fair Sennheiser has already created the ultimate classical headphone with hd800/800s.

For most of us, given the capacious offerings of 6x0 interations it will often come down to preferences. Some will prefer the 650 to the 600. And now some will opt for the 660s2 over the 650/600. I appreciate the effort Sennheiser has made with the 660s2. But for me and my preferences, it doesn’t quite hit the mark and will not oust the 650 as my favorite in the lineup. If you’ve ever been a musician or been around live music a lot, natural tone will always sit at the top of your list when listening to music with headphones.

Regarding amping. I do most of my testing on the THX789. It’s a fairly neutral amp without much coloring to the signature. When I switched over to the Valhalla 2 and more so when switching to the Bottlehead Crack, the 650 easily pulled ahead of the 660s2. For me, it came down to the ability of the 650 to capture and captivate with those rich, natural vocals causing me to be captivated by the music. While 660s2 did improve on both tube amps, it simply didn’t seem to “scale” as well as the 650. Perhaps on different/more expensive tube amps the results would be different.


660s2 Pros:

*nice looking (best in the lineup)

*design and build are tried and true

*good attempt to improve the sonics in the 6x0 series

*improved dynamics and staging


660s2 Cons:

*doesn’t match the ability to “scale” as well as the 650 or match the 650 “tonality”

*packaging is disappointing at this price

*ultimately does not dethrone the king

Final Edit:

After my review I put the s2 away and listed them for sale. Since they were boxed up for shipping, they were no longer being listened to or reviewed. When I didn’t get an offer on them, I decided to pull them back out and give them another listen. But this time was a little different. I wasn’t listening critically or comparatively against my 650. Also, I decided to listen to the s2 exclusively for several days. And then, something odd happened. I honestly began to really enjoy them. That splash of extra bass and touch of sparkle at the top began to grow on me. I thought to myself, “man, these are actually quite good.” Over the course of the next 5-6 listening sessions with my favorite albums I found myself at the end of the session thinking that the was the most I’d EVER enjoyed listening to that album! That is significant for me. These are recordings that I’ve listened to a hundred times with tons of headphones.

So do I rank them higher than I did originally? Did the extra break in time benefit the sound or did my brain break in with time? And finally, do I rank them better against my 650 than I did originally? At the end of the day, I do think that they are better than I judged them originally. If I’m honest, I probably do suffer from a bit of a love affair with my 650. The s2 is a very good headphone and deserves to be on the short list for anyone looking at the 6x0 series.

Awesome review! I feel the same way about my HD600 and 6XX vs other headphones I have. The original 6X0 headphones just sound too solid to really be trumped by anything else I have. However, I think direct upgrades from the HD600 to the 660S2 could be things like imaging, instrument separation, resolution, and overall depth to the music. In terms of tonality though, it's funny because you literally can't go wrong with either of the 600, 6XX/650, or 660S2. They're all good. Lately I've been enjoying my 660S2 a LOT on my Modi Multibit and Asgard 3 amp. The nice timbre and tonality of the HD600 is still in the DNA of the 660S2, just tweaked a bit, and I can appreciate that. I think it captures what I love about both the HD600 and 6XX/650.

Also, I find that some headphones get better the more you use it. Which is probably obvious, but I found this most often with my Arya v2. I sometimes feel very "eh" about it when I first put it on. But a week goes by and I struggle to go to bed because I don't wanna take it off haha.

 

[Click]

Just want to say, Cayin RU6 is a spectacular pairing with the 660S2 (and HD700). The timbre, details, and resolution are so good.

RU6 has more than enough power to drive these Sennheiser headphones, especially in high gain mode. I was worried it might not have enough juice, but it does.

 

[skeeb23]

I was surprised on how much easier to drive the 660s2 was based off of just knowing they were 300 ohm. Impedance definitely doesn't tell the whole story.

When I had them I found them to play well with the iFi go bar, so not surprised you liked them on the RU6. Especially with the 4.4 to my Go Bar. I did also enjoy them on tubes. I liked also how my LP added a bit more to the space/staging. I know many say they are more intimate, and I understand why that is said. Still, I felt they had a natural presentation of the stage. I suppose comparing to like my Radiance which is much more in my head (and closed back).

I do enjoy bass and felt they were bass light, but still felt they could satisfy enough and not leave me too starved for it. Great headphone and I only wish I had a 660 to compare to.

 

[ericpalonen]

When I had them I found them to play well with the iFi go bar

I enjoy this combination quite a bit as well. Very "percussive" and plenty of headroom. Smooth top-end with a flattering glue. I love the addition of 4.4 bal on these DACs!!!!

 

[Shane D]

I was surprised on how much easier to drive the 660s2 was based off of just knowing they were 300 ohm. Impedance definitely doesn't tell the whole story.

When I had them I found them to play well with the iFi go bar, so not surprised you liked them on the RU6. Especially with the 4.4 to my Go Bar. I did also enjoy them on tubes. I liked also how my LP added a bit more to the space/staging. I know many say they are more intimate, and I understand why that is said. Still, I felt they had a natural presentation of the stage. I suppose comparing to like my Radiance which is much more in my head (and closed back).

I do enjoy bass and felt they were bass light, but still felt they could satisfy enough and not leave me too starved for it. Great headphone and I only wish I had a 660 to compare to.

I also find them super easy to drive and was surprised. They were great off all my amps, especially the iFi, with a bit of bass boost. That may been a bit too much, but it was fun. I am pleasantly surprised with the bass. As I have described it, not Focal level, but way ahead of Grado's. You would never put on a Grado or Sennheiser and expect big bass, anyway. I have headphones for bass, but these are a nice musical headphone. I don't feel anything is lacking, which I couldn't say for the HD600, HD6XX, HD58X, HD660S, etc.

 

[MattTCG]

I've had more fun, pure enjoyment and wow moments with the s2 in three weeks than I had with the OG 660 in a year. There is just a really nice balance with them of pushing the envelope of the series without going too far.

I was concerned that the extra treble would be too much and inevitably fatiguing. It's not. While there is clearly more treble extension, it comes across "smooth" and never peaky or shrill. I was worried that the extra bass would bleed into the midrange and ruin the vocal centric music that I enjoy. It doesn't. This is a pretty good headphone.

 

[Guinibee]

After spending an audition period with the 660s2 and being a long time 650 owner, I thought I’d chime in with a few thoughts and comparisons. I won’t waste any time regurgitating the basics regarding build quality, cables, specs etc as those have been hashed out plenty by now. All of my findings are in comparison to the 650 unless otherwise noted.

At the initial listen the first impression that pops out at me is that there is in fact a splash more bass response with the 660s2. To be more accurate, to my somewhat educated ears, the improved bass response seems to be approximately 2db (possibly 3db) more than I’m used to with my trusty 650. Of course, one of the most popular complaints with 650 owners is that lack of (sub) bass and the associated impact that goes with it. Let me note here that most popular music is NOT recorded with sub bass frequencies. However, electronic music is more prone to use actual sub bass response in the frequency range at around 30hz or lower. I like to use the album “Unit” by Scann-Tec to test true sub bass response. The second track on this impressive EDM offering is particularly good at getting down to 30hz with good impact and remaining texturally intact. While the 660s2 does outperform the 650 with bass response on this track, it’s only by a modest margin. I’ve heard many superior efforts by other headphones at producing this track that way that the bass was meant to be experienced. For example, the ETHER 2 by DCA delivers the bass response in this track impressively and somewhat shockingly when compared to the 660s2. Comparatively, the 650 relies more on the infamous “mid-bass hump” to achieve is sonic signature. For me, this works outs wonderfully because I don’t listen to a lot of EDM music anyway and the mid bass hump gives a richer slightly warmer sound to the music I prefer.

Truth be told, 650 owners typically don’t buy this headphone for its impressive bass response, as a planar magnetic offering will almost always have a clear advantage in that capacity. We 650 lovers buy the 650 for the magical midrange. And we’re willing to accept “decent” bass and “smooth” treble as part of the package. Moving on, the treble is in fact “cleaner” and more extended on the 660s2. Has Sennheiser fixed the second shortcoming on my almost perfect 650? Well, sort of. Female vocal tracks that peek into the lower treble range do come across more airy and revealing with the 660s2 if not a little nasally and not quite as natural as on the 650. I will concede that classical music, particularly when an orchestra is led by a violinist, offers better clarity and resolution on the 660s2. In fact, classical music in general plays out better on the 660s2. To be fair Sennheiser has already created the ultimate classical headphone with hd800/800s.

For most of us, given the capacious offerings of 6x0 interations it will often come down to preferences. Some will prefer the 650 to the 600. And now some will opt for the 660s2 over the 650/600. I appreciate the effort Sennheiser has made with the 660s2. But for me and my preferences, it doesn’t quite hit the mark and will not oust the 650 as my favorite in the lineup. If you’ve ever been a musician or been around live music a lot, natural tone will always sit at the top of your list when listening to music with headphones.

Regarding amping. I do most of my testing on the THX789. It’s a fairly neutral amp without much coloring to the signature. When I switched over to the Valhalla 2 and more so when switching to the Bottlehead Crack, the 650 easily pulled ahead of the 660s2. For me, it came down to the ability of the 650 to capture and captivate with those rich, natural vocals causing me to be captivated by the music. While 660s2 did improve on both tube amps, it simply didn’t seem to “scale” as well as the 650. Perhaps on different/more expensive tube amps the results would be different.


660s2 Pros:

*nice looking (best in the lineup)

*design and build are tried and true

*good attempt to improve the sonics in the 6x0 series

*improved dynamics and staging


660s2 Cons:

*doesn’t match the ability to “scale” as well as the 650 or match the 650 “tonality”

*packaging is disappointing at this price

*ultimately does not dethrone the king

Final Edit:

After my review I put the s2 away and listed them for sale. Since they were boxed up for shipping, they were no longer being listened to or reviewed. When I didn’t get an offer on them, I decided to pull them back out and give them another listen. But this time was a little different. I wasn’t listening critically or comparatively against my 650. Also, I decided to listen to the s2 exclusively for several days. And then, something odd happened. I honestly began to really enjoy them. That splash of extra bass and touch of sparkle at the top began to grow on me. I thought to myself, “man, these are actually quite good.” Over the course of the next 5-6 listening sessions with my favorite albums I found myself at the end of the session thinking that the was the most I’d EVER enjoyed listening to that album! That is significant for me. These are recordings that I’ve listened to a hundred times with tons of headphones.

So do I rank them higher than I did originally? Did the extra break in time benefit the sound or did my brain break in with time? And finally, do I rank them better against my 650 than I did originally? At the end of the day, I do think that they are better than I judged them originally. If I’m honest, I probably do suffer from a bit of a love affair with my 650. The s2 is a very good headphone and deserves to be on the short list for anyone looking at the 6x0 series.

Oh wow I was one of the people looking to buy your S2! I'm glad you gave it another shot, it's phenomenal! I've had all the other 6x0 headphones and there's just something fun about the S2 that for casual listening is so great.

I have been looking for a good deal on one. First time I got it was at the retail and I didn't want to keep it for that much. I saw an open box deal at $450 I think I'll grab. Wondering if any Independence day deals will show up but I think the $500 deal is the best for new I'm seeing.

 

[SchwizzelKick66]

4 months and I'm still blown away by the 660S2.

Listening to Snarky Puppy's latest album Empire Central while I work from home today, and every track just sounds incredible. This is how I want a headphone to sound man. And after listening through the entire album there is zero discomfort.

These things are just amazing. At current sale price of $499 I don't think they can be beat. Possibly the best headphones on the market IMO.

 

[Guinibee]

4 months and I'm still blown away by the 660S2.

Listening to Snarky Puppy's latest album Empire Central while I work from home today, and every track just sounds incredible. This is how I want a headphone to sound man. And after listening through the entire album there is zero discomfort.

These things are just amazing. At current sale price of $499 I don't think they can be beat. Possibly the best headphones on the market IMO.

Coming from someone with a 800s too! Yeah I think I'm going to grab that open box deal!