[Freo-1]

I've been a headphone enthusiast for many years.  For what ever reason, I never had bought or listened to the Sennheiser HD 600 headphones. 


I recently corrected this obvious oversight.  Bought a pair of HD 650's recently.  To say I was surprised is a understatement.  I've had headphones costing up to 1500.00 that didn't sound this good.  Easily one of the most neutral sounding headphone I've ever heard.  The only knit against them is that the sub bass is low compared to other headphones.  This is not a big deal for most music, unless you are a bass head, in which case, look else ware.   Otherwise, these headphones may be all one needs to enjoy music for long listening sessions.  They are very light, at 260 grams, and well built.  Many people have owned them for 20 years or more. 


I was so taken with the HD 650, when I saw a sale from Amazon for the HD 600, I had to get them.  They are slightly different sounding, but share a very similar house sound.  The HD 600 is a bit more analytical, whilst the HD 650 is a bit warmer and more forgiving.  The differences are slight, but noticeable. 


The sound can be further improved by using Sonarworks Sound Reference S/W for headphones.  It provides a small amount of EQ for the 600 and the 650.  Combine that with PGGB-RT via Foobar2000, and one can get very high quality sound from a reasonably priced set of headphones.


https://www.sonarworks.com/blog/reviews/sennheiser-hd650-review

[Letitroll98]

Although I've never owned a pair, I've always liked the 600 series Sennheiser phones.  Between these two I agree that I slightly prefer the 650, but would be happy with either.  What I haven't heard is the 660S2 which solely from reviews seems more in my wheelhouse.  Any thoughts?

[Freo-1]

Although I've never owned a pair, I've always liked the 600 series Sennheiser phones.  Between these two I agree that I slightly prefer the 650, but would be happy with either.  What I haven't heard is the 660S2 which solely from reviews seems more in my wheelhouse.  Any thoughts?

Most of the reviews I've come across seem to not like the HD 660 S2 as much as the HD 650.  I have been itching to try them out myself. 


I like the 600 slightly more with Jazz/Classical, and the 650 more with rock music.  The Sonarworks S/W does improve them both, making them almost identical.

[FullRangeMan]

Thankyou for your impressions.
How big is the soundstage?

[Bodhi]

+ 1. The Sennheiser HD 650 cans are sensational value, and will likely be the next headphones I buy.

[Freo-1]

Thankyou for your impressions.
How big is the soundstage?

The soundstage is good, but not overly expansive.  It is very precise with placement.  These headphones do need a quality headphone amp (section) to sound their best.  At 300 ohms, they do require some power.

[Freo-1]

Although I've never owned a pair, I've always liked the 600 series Sennheiser phones.  Between these two I agree that I slightly prefer the 650, but would be happy with either.  What I haven't heard is the 660S2 which solely from reviews seems more in my wheelhouse.  Any thoughts?

Your post piqued my interest.  Have the HD 660 S2 arriving this week.  I'll post some impressions and let you know.

[Bill Baker]

I haven’t heard the 650’s but I have had the HD600’s for a couple years. I don’t get to use them often as they are for testing. I can say I have no desire to get anything else. I want to put together a small headphone setup so I can enjoy them more often. They do very well with both tube and solid state and are very clean and detailed.

[Jon L]

I have way too many $$ headphones but currently own zero "normal" dynamic headphones.  If I had to buy one, I would buy the HD600 and use better headphone cables into a decent tube headphone amp and be done with it.  I have always enjoyed that combo 

[FullRangeMan]

IMO a balanced cable are very important.

[Freo-1]

Although I've never owned a pair, I've always liked the 600 series Sennheiser phones.  Between these two I agree that I slightly prefer the 650, but would be happy with either.  What I haven't heard is the 660S2 which solely from reviews seems more in my wheelhouse.  Any thoughts?

Just got the 660 S2 in house.  Very nice headphones.  Seems to be a touch more detailed than the HD 650.  They definitely share the Sennheiser house sound.  They do have more bass than the HD 650.  The midrange is similar to the HD 650, but the HD 650 may be just a tad more transparent.  I think it depends on the recording.  The treble has more energy and sparkle than the HD 650, but the difference is small. 


Honestly, I like both a lot, and either one makes for excellent listening.  The HD 660 S2 may be more to your liking, based on your comments. 
I'm using Sonarworks for all my HD 600 series headphones, so that seems to make them sound more like one another, due to the EQ. 


It's like having three different Single Malt Scotch from the same area.  More alike than not, but each with it's own distinct flavor.

[Letitroll98]

Appreciate the comments Freo.  But I have to ask did you listen without the Sonarworks EQ before making the evaluation?  Judging from your comments compared to other reviews it's hard to tell.  I checked out Sonarworks after your post on it and it seems to do a great job of making every headphone sound the same, at least that's what they advertise.  However your assessment seems to match others non EQ'd impressions, same house sound, in between the 600 and 650 in transparency, but with more bass.  That's what I'm reading.

[Freo-1]

Appreciate the comments Freo.  But I have to ask did you listen without the Sonarworks EQ before making the evaluation?  Judging from your comments compared to other reviews it's hard to tell.  I checked out Sonarworks after your post on it and it seems to do a great job of making every headphone sound the same, at least that's what they advertise.  However your assessment seems to match others non EQ'd impressions, same house sound, in between the 600 and 650 in transparency, but with more bass.  That's what I'm reading.

Your comment is accurate.  I have tried all the 600 series with and without the Sonarworks.  The 660 S2 definitely has more bass, and an extended treble.  The midrange with 660 S2 is still very good, but just a shade less transparent than the 650 or 600.  How much the differences are noticed depend on the source recording.  There are some jazz recordings where I prefer the EQ off, but generally the EQ improves the sound. 


The midrange is where I still prefer the HD 600 or HD 650 overall.  EQ really helps the HD 660S2.


The EQ helps, but it doesn't make all the 600 series sound "exactly" the same.  The flavor differences are still there, just not as pronounced.