[Sal1950]

My Emotiva Stealth DC-1 has a very over sized power supply along with a defeatable +2 db boost at 20hz.  I think it makes an awesome match for the HD 650s controlling the bottom end with an iron like grip. Also sounding very clean and smooth across the rest of the audio band.  YMMV

 

[titaniumx3]

My 2010 and 2015 HD650 sound pretty much the same now after several hours of use. The new one still sounds a little compressed and not as 'alive' as the old one, but that's most likely due to the rigid ear pads. The old one is super soft and hugs my head like a glove. I even recall my old 650 sounding the same when I first got it back in 2010, had to use it for several weeks before the sound stabilised.

 

[LugBug1]

  I would like to add my two cents.
 
2009 HD650 vs 2015 HD650
 
I know for a fact that Senn has changed the tuning on the HD650 driver over the years even on the Silver driver versions.
I'm on my 2nd HD650, the 1st one was bought in 2009. It came in a silver case which came inside a silver corrugated paper box. The 2009 HD 650 is still going strong sonically, just beat up cosmetically. This 2009 HD650 had the silver drivers and paired with the HA 160D I didn't find the sound to be veiled or muddy. Burson's design brief for the HA160 was to drive the HD650 effortlessly since it was one of the most difficult to drive cans on the market so if the HA160 could drive the 650 effortlessly other cans available at the time would pose no problem.
 
This 2009 HD 650 out of the box had the vice like grip 650's are known to have and to loosen it I had to put in on a 10 inch wide bookshelf speaker(treating the speaker like a head) for weeks. This helped reduce the clamping force and the headphone became very comfortable.
 
Now this HD 650 had AWESOME bass weight and impact just like what Mike from headfonia says. The bass was weighty and detailed with very good extension. I also bought a HD598 in 2010 and compared to that the 2009 model HD650 was way ahead, more air, a presentation that was pulled further back, better timbre and the bass slam, weight and impact was waaay ahead of the 598.
 
Fast Forward to 2015
 
I really like the HD650 and since the old one was looking pretty beat up I decided to go for a new 650.
 
Going by my previous experience I was prepared to go through to vice like grip loosening phase but.....
The November 2015 manufactured HD650 had a very light clamping force out of the box which was at par with the 2009 HD650 after the bookshelf speaker loosening period.
 
2nd difference was the box was now black and the headphone case is dark grey.
 
BUT THE BIGGEST DIFFERENCE B/W THE TWO WAS THE SOUND
 
The 2015 HD650 had no bass weight(even less than my 2010 HD 598) and had lost its laid back character, the sound has a forward presentation plus the treble is boosted and sounds like when 12kHz-16kHz region is given a+3.5dB boost. I still have the HA 160D and compared both the headphones on the same setup. Headphone was burned in for 200+hours. 
 
The timbre, instrument separation, bass extension and detail retrieval is same but the tonality is different and the bass weight is absent. Gone is the warm laid back presentation. Sennheiser HD650 just pulled an Audeze.
 
2009 HD650 is a laid back warm sounding can with AWESOME bass weight and slam when needed but the 2015 HD650 is completely lacking in this department, its neutral sounding with boosted highs. 
 
My old 650 has thousands of hours on it and the new one has less than 300 hours on it. I'll keep using the 2015 HD650 and report if the bass opens, if not Sennheiser has once again covertly changed the sound tuning of the HD650. These difference were also there when the cans were used with a Burson Conductor Virtuoso.

Completely agree with the treble boost, but the bass sounds the same to me (to older silver driver models). Maybe a little tighter. 

 

[Headzone]

How can they change the sound of the headphones so drastically with no information on the product site - or elsewhere?

 

[castleofargh]

 

Spoiler: Warning: Spoiler!

I would like to add my two cents.
 
2009 HD650 vs 2015 HD650
 
I know for a fact that Senn has changed the tuning on the HD650 driver over the years even on the Silver driver versions.
I'm on my 2nd HD650, the 1st one was bought in 2009. It came in a silver case which came inside a silver corrugated paper box. The 2009 HD 650 is still going strong sonically, just beat up cosmetically. This 2009 HD650 had the silver drivers and paired with the HA 160D I didn't find the sound to be veiled or muddy. Burson's design brief for the HA160 was to drive the HD650 effortlessly since it was one of the most difficult to drive cans on the market so if the HA160 could drive the 650 effortlessly other cans available at the time would pose no problem.
 
This 2009 HD 650 out of the box had the vice like grip 650's are known to have and to loosen it I had to put in on a 10 inch wide bookshelf speaker(treating the speaker like a head) for weeks. This helped reduce the clamping force and the headphone became very comfortable.
 
Now this HD 650 had AWESOME bass weight and impact just like what Mike from headfonia says. The bass was weighty and detailed with very good extension. I also bought a HD598 in 2010 and compared to that the 2009 model HD650 was way ahead, more air, a presentation that was pulled further back, better timbre and the bass slam, weight and impact was waaay ahead of the 598.
 
Fast Forward to 2015
 
I really like the HD650 and since the old one was looking pretty beat up I decided to go for a new 650.
 
Going by my previous experience I was prepared to go through to vice like grip loosening phase but.....
The November 2015 manufactured HD650 had a very light clamping force out of the box which was at par with the 2009 HD650 after the bookshelf speaker loosening period.
 
2nd difference was the box was now black and the headphone case is dark grey.
 
BUT THE BIGGEST DIFFERENCE B/W THE TWO WAS THE SOUND
 
The 2015 HD650 had no bass weight(even less than my 2010 HD 598) and had lost its laid back character, the sound has a forward presentation plus the treble is boosted and sounds like when 12kHz-16kHz region is given a+3.5dB boost. I still have the HA 160D and compared both the headphones on the same setup. Headphone was burned in for 200+hours. 
 
The timbre, instrument separation, bass extension and detail retrieval is same but the tonality is different and the bass weight is absent. Gone is the warm laid back presentation. Sennheiser HD650 just pulled an Audeze.
 
2009 HD650 is a laid back warm sounding can with AWESOME bass weight and slam when needed but the 2015 HD650 is completely lacking in this department, its neutral sounding with boosted highs. 
 
My old 650 has thousands of hours on it and the new one has less than 300 hours on it. I'll keep using the 2015 HD650 and report if the bass opens, if not Sennheiser has once again covertly changed the sound tuning of the HD650. These difference were also there when the cans were used with a Burson Conductor Virtuoso.

 

I can think of a few problem with that analysis:
-did you own all models at the same time at one point? else you rely on memory and that's not the most reliable tool.
 
-after some years, the headphone will burn-in/get old, the filters, foam etc might get dirty and in the process have a bigger dampening factor. the magnet might lose a few percent of it's strength or whatever. just the stuff getting older.
 
-did you swap the drivers and pads to make sure it wasn't just the headbands being more or less bents or just not being at the same length setting? clamping differences would most certainly explain the low end losing strength/loudness for example.
 
-how can you be sure that no variation would have appeared if you had bought 3 hd650 at the same time? from measurements of headphones, it seems to be very common to have some manufacturing differences that end up building up into a few db variations from one pair to another. in fact it's already obvious when looking at right vs left measurements(as long as we trust the measurement gear) that each side is a little different.
 
so differences between your pairs, don't necessarily mean the headphone signature was tweaked. it's very much possible, but your experience does not have enough to demonstrate it IMO.

 

[titaniumx3]

The difference is mostly to do with the softer pads and looser headband. I'm sure there's some measurable physical changes in the driver over a period of time, but its going to have a minimal effect on the sound compared to the change in the earpads and headband over time.
 
You can see in the pictures I posted before that the pads on my old 650 are significantly flatter than the new one, and a lot softer, so much so that they feel like they are using a different stuffing material. I had also washed and tumble dried the pads on my old 650 the day before so they regained some of their original shape; normally they are even flatter than that. The difference this makes to the sound is no small thing. Just push your earcups against your head or simply lift them slightly (to break the seal) and you'll hear a relatively drastic change in sound. 
 
As I said before, my older 650 had a similar sound to my current 650 when I first got that. The sound changed over time as the pads softened and took on the shape of my head.

 

[whirlwind]

I hope everybody had a wonderful Christmas.
 
I feel very fortunate to be where I am in life and I enjoyed spending time with all of my family, wish we could do it more often.
 
I have four days off for the holidays and I am able to spend today listening to my HD650.
 
I am listening to one of my go to albums, it is a collection of some of his beat live performances, up until 2008...the recordings are wonderful.
 

I am listening with a wonderful warm and tubey sound that I adore with the HD650.....I could listen to this combo for hours on end, with absolutely no fatigue and absolutely no edge to the upper end what so ever.....I could not be in a better place right now.
 

 
GEC 6080 Power Tubes & Brimar 13D1 Driver
 
A warm , but dynamic combo that sounds wonderful with the HD650
 
What a wonderful headphone, we are all fortunate to own one. 

 

[raybone0566]

I hope everybody had a wonderful Christmas.

I feel very fortunate to be where I am in life and I enjoyed spending time with all of my family, wish we could do it more often.

I have four days off for the holidays and I am able to spend today listening to my HD650.

I am listening to one of my go to albums, it is a collection of some of his beat live performances, up until 2008...the recordings are wonderful.



I am listening with a wonderful warm and tubey sound that I adore with the HD650.....I could listen to this combo for hours on end, with absolutely no fatigue and absolutely no edge to the upper end what so ever.....I could not be in a better place right now.




GEC 6080 Power Tubes & Brimar 13D1 Driver

A warm , but dynamic combo that sounds wonderful with the HD650

What a wonderful headphone, we are all fortunate to own one. 

Well put Joe, beautiful amp and great album as well. Really looking forward to that Glenn amp. Enjoy

 

[kvn864]

what exactly is this amp with 5 tubes?

 

[whirlwind]

  what exactly is this amp with 5 tubes?

It is an OTL amp, made by Glenn, who is a member here on the forums and builds amps in his spare time.

 

[whirlwind]

 

I hope everybody had a wonderful Christmas.

I feel very fortunate to be where I am in life and I enjoyed spending time with all of my family, wish we could do it more often.

I have four days off for the holidays and I am able to spend today listening to my HD650.

I am listening to one of my go to albums, it is a collection of some of his beat live performances, up until 2008...the recordings are wonderful.
 

Spoiler: Warning: Spoiler!

I am listening with a wonderful warm and tubey sound that I adore with the HD650.....I could listen to this combo for hours on end, with absolutely no fatigue and absolutely no edge to the upper end what so ever.....I could not be in a better place right now.
 

Spoiler

GEC 6080 Power Tubes & Brimar 13D1 Driver

A warm , but dynamic combo that sounds wonderful with the HD650

What a wonderful headphone, we are all fortunate to own one. 

Well put Joe, beautiful amp and great album as well. Really looking forward to that Glenn amp. Enjoy

Thanks, and congrats to you on getting in the que for an amp.
 
I am almost positive that you will enjoy any creation that Glenn makes for you, I am sure it will be special  

 

 

[Sal1950]

  It is an OTL amp, made by Glenn, who is a member here on the forums and builds amps in his spare time.

Very sexy looking  piece of gear!  I wonder how much current it sucks from the wall to deliver a few mW of audio to your phones?  LOL

 

[flaming_june]

Basically, from what I've read, if you're after the warm sound of the famed 650, don't get the 2015 version.
 
So if I have lcd2, t1, hd800, grado rs1, the hd650 doesn't fit in any niche use, am I right?

 

[LugBug1]

  Basically, from what I've read, if you're after the warm sound of the famed 650, don't get the 2015 version.
 
So if I have lcd2, t1, hd800, grado rs1, the hd650 doesn't fit in any niche use, am I right?

 
In a nutshell yes. But I would also add, after spending a week now with my new 650's the sound is fairing well for my tastes. These are so clear, vibrant and balanced. Kind of a warm/bright Grado-esque feel (not as peaky) but with the Senn imaging and soundstage. There is great attack and control - They resolve incredibly fast and I'm really enjoying going through my contemporary classical stuff and hearing every crook and cranny. Vocals are also very realistic - more so than HD800 imo. The bass has a nice feel and rumble (if you feed them enough power) and doesn't bleed into the middle, it is still emphasised a little at lower mid to add a little fun. I could do with a little more sub bass however, but this is where you start to get bloom if you are not careful with open headphones. Sennheiser in this respect have opted for tightness instead.
 
I also want to stress, that Sennheiser have not turned the 650 into a bright headphone. It is a brighter headphone than what it was ime. It may please some. It may be too late to please all the folk that didn't like it originally. So it may backfire on them... I personally think that they are soon going to drop the hd600 as I see no point owning it comparing it to how the 650 sounds now.

 

[mysticstryk]

Maybe you got a weird hd650. If the newest versions were that different, we would be hearing more reports about it IMO.