[FredrikT92]

How do u check when ur unit is manufactured?

 

[solblack]

Yes Sennheiser are one of the great companies in head gear

I love the 650

 

[Kramer01]

FredrikT92

The new black box packaging mentions the month on the label.

Older silver corrugated paper packaging just had a serial number sticker on it.
You can email the serial number to Sennhieser and ask them the manufacturing date/month.

 

[mysticstryk]

  I tried replugging in the left cable multiple times to the left speaker and it didn't work. Really weird -_-. Is it wrong to have my headphones out in the open? I haven't opened it to check for dust in years. 

 
That is odd.  I mean, if you had them sitting out in the open for a long time, I suppose it is possible that dust could get in.  I'm not sure if that could cause damage like that though.

 

[Sal1950]

   
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.

Mine were made in very early 2015.  Personally I'm not looking for a warm or any other flavor of sound. I would prefer them to be as accurate as possible in my price range. Which is what I get from my HD 650s IMHO.  If I wanted a flavor of sound I would add EQ.

 

[EinZweiDrei]

I still wouldn't call the hd650 neutral. Neutral with slight warmth best describes the hd600. Atleast to my ears. They are both equally good headphones. Their midrange is probably the best i'll ever get to hear at it's price range. Not that i've heard that many headphones anyways. To me the hd650 is a little on the bassy side. But both senns seem to lack sub bass. Does the old hd650 have more audible sub bass than the new ones? Both my hd6xx are fron 2015.

 

[LugBug1]

  I have a pair from late 2012 and the ones I got about 3 months ago, I hear no difference between the two.  I bought the second pair because I liked them so well did not want to lose out if they broke.  Now about to receive hd700 tonight so maybe I will like them more, at least enough to let one pair go.  We shall see.  Sennheiser made no change to the drivers, since the silver as opposed to black drivers, the newer pads are stiffer and there in lies the difference.  Check out this link about pad thickness and you may understand the difference...https://diyaudioheaven.wordpress.com
/headphones/measurements/brands-s-se/......    

HD650 pads​

The measurements of the headphone above are made with a black driver + old type pads.
Most likely the old pads once were a bit stiffer and the foam inside will be somewhat decayed/softened over time.
The newer pads indeed sound ‘brighter‘ and ‘clearer‘ and relatively the old pads sound ‘darker’ or ‘warmer’ with less clarity/treble presence.
I was curious what caused the differences as side by side they looked very similar in height.
The old pad = 30mm high, the new pad 32mm, the colour of the new pad is darker and the velours of the newer pads feel less ‘soft’ to the skin.
The new pads also come with new foam inlays.
The new pads have the product code: 050635. They are suited for HD545 / HD565 / HD580 / HD600 / HD650 / HDI850.

Time for some measurements to show the differences between the 2 pads (right channel only).
The measurements are done with the same test-voltages from a low output R amplifier and the same driver/channel.
The old pad has a good 2dB more presence below 1000Hz and is also a bit louder in SPL. The amount of treble (> 4kHz) is about the same level.
The new pad is more balanced and the ‘warmer’ signature is gone. More towards the HD580 / HD600 signature.

What isn’t very obvious when wearing these is the fact that the old pads compress a lot more than the newer (less compliant) ones.
When placed on the test rig this became quite evident though.
Quite possible the older pads may create a slightly better seal on some heads (depending on bone structure) as well.
Using the older pads the drivers are thus much closer to the ears which results in a slightly higher SPL below 1kHz.
To check if the pad thickness is indeed the only parameter that changed I pressed the new pads against the rig to the same driver-rig distance as the old pads did by themselves. Below the result of this small test.

This test shows that the newer pads do not have any different absorbtion or other acoustical effects and the differences in sound signature and SPL between the two pads is now the same. They sound equally ‘warm’ under these conditions.
What became quite obvious is that while the old and new pads differ only slightly in height when laying flat on the table (30mm vs 32mm) as shown in the picture above, but the pads compress in a substantially different way when being pressed against the skull with the same clamping force.
Below 2 pictures of both pads with 1kg weight on top of them. Roughly equating to about 10 Newton force which is a bit north of firm pressure but it shows the differences better.
With 10N on the entire surface of the pads the total height of the pads was reduced from 30mm to 20mm. Considering the mounting plate was also included (which is 5mm) the actual pad thickness reduced from 25mm to 15mm a 40% reduction.

Below a picture of the new pads with the exact same weight pressing on it. With 10N on the entire surface of the pads the total height of the pads was only reduced from 32mm to 27mm. Considering the mounting plate was also included (which is 5mm) the actual pad thickness reduced from 27mm to 22mm a 20% reduction.

The question of course is whether or not the old pads had been (much) stiffer when new which is quite likely as the foam inside the pads deteriorates over the years.
If that’s indeed the case then the sonic signature must have become ‘warmer’ over the years without me really noticing it….

Amplifier output resistance effect​

Due to the impedance characteristics of the HD650 the headphone changes its sonic signature slightly when fed from either a low output R amplifier (0.1Ω) or  a higher output R amplifier (120Ω). Because of the relatively high impedance of the headphone (around 300Ω) the effect isn’t nearly as dramatic as it can be on lower impedance headphones. Below a plot of the HD650 (with new pads) when driven from a 0.1Ω amplifier and a 120Ω output amplifier (Ember prototype was used).

As can be seen the mid bass is increased by about +1dB and the upper treble by about +0.5dB.
The SPL was level matched at 1kHz to compensate for the level differences caused by voltage division. The CSD showed no differences other than the small level differences.

Interesting post and I believe every part of it, thanks for sharing. I know that different pads material/height/softness etc can make a substantial difference to the sound. And of course the wear of pads is inevitably going to effect it also. I did change my pads 3 times over the course of owning my earlier 650's and as late as 2011-12. So the point you raise doesn't apply to my experience. I also had the silver driver version. 
 
What does convince me that they are now brighter is when I swap over to the K701 (original 7 bump) and find the 650 is in fact brighter. Not as peaky in the upper mids but most certainly brighter lit in the treble as a whole. Now, the trebles of these headphones are very different and I'm only using this comparison for this crude purpose of point. Ask anyone who owned or tried both these headphones in the naughties (I did) and they will tell you which one was the brightest. 
 

  Mine were made in very early 2015.  Personally I'm not looking for a warm or any other flavor of sound. I would prefer them to be as accurate as possible in my price range. Which is what I get from my HD 650s IMHO.  If I wanted a flavor of sound I would add EQ.

They are indeed very accurate. Especially vocals (best I've heard yet for voice I think).

 

[flaming_june]

You should at least audition it.opinions rounds these parts vary greatly and may steer you away from a phone you may vary much enjoy. I've got the 800 in house now. The more I listened to the 650 the less time the lcd got so I sold them. Bought mine in late 2014, great phones. Do give them a listen

 
Uh oh.... 
 
Quote:

Just a quickie about Grados. You also get a smoother treble response IMO, if you raise the output impedance. I know that this goes against what gurus state with amp output impedance, but I think the Grados are better sounding driven this way!

 
Definitely the case.

 

[Sal1950]

  Thanks......not sure how much current it sucks from the wall....but I do know that when you use these monsters to run your low z cans....your listening station gets about 5 degrees warmer  

 

 
These beast draw 5 amps of heater current apiece!.....but they give my grado cans a wonderful bass.

Yea, it really doesn't matter as long as they sound sweet. My VTL Compact 80s could warm the whole room in the winter, but man that sound. WOOT

 

[FredrikT92]

I'm tempted to try another amp with my HD6XX. 
Currently got the WA6-SE. Is there something you guys would especially recommend? OTL?`

 

[castleofargh]

@castleofargh

I think you didn't read the post carefully and my opinion is not based on memory. I still have both the 650's and the 598.

I had the earpads and headband replaced around 2 weeks back so both the 650's have pads with approximately the same use on them.

The new 650 isn't as warm/lush as the old 650.
The new one is neutral with a hint of warmth. It'smore resolving and a bit clearer.
The bass is there and it still goes deep and is detailed but its not as weighty/visceral as b4.

Listening to Lorde's Royals on the new 650 and the low bass just does not have the same bass weight of the old 650.
Plus there is more treble.

The pulsating beats of the opening track of DSOT have more weight on the old 650.

Listening to well recorded music is more fun on the new 650 because its a bit clearer and better resolving so you can hear deeper into the recording or maybe the reason for the more resolving nature is that the new 650 has lost the "overt" bass heaviness that 650's have historically been associated with.

As I stated in the original post my old 650 has thousands of hours on it and the new one has less than 300. I'll continue to burn in the new 650 for another 500+ hours and then report if the bass opens up or remains as it is.

My first audiophile can was the 650 and I bought it along side the Burson HA 160D. This was my only listening setup for 3 years. I also bought a 598 aftera while but that didn't see much use since I liked the 650 more.

I don't see how that disagrees with my warning about the conclusion. just look at the right vs left measurements of a hd650, that should be enough to accept that several hd650 may not sound exactly the same anyway. I'm at no moment dismissing your hypothesis. I'm just saying keep the others in mind too as long as you can't rule them out.

 

[donlin]

 
I don't see how that disagrees with my warning about the conclusion. just look at the right vs left measurements of a hd650, that should be enough to accept that several hd650 may not sound exactly the same anyway. I'm at no moment dismissing your hypothesis. I'm just saying keep the others in mind too as long as you can't rule them out.

I have a feeling there is more sample to sample variation than we would like to think (the idea of buying multiple versions of the same phone to find the "best one" could lead to insanity).  Audeze is accused of this quite a bit but it must happen with everybody to some extent.

 

[castleofargh]

 

 
I don't see how that disagrees with my warning about the conclusion. just look at the right vs left measurements of a hd650, that should be enough to accept that several hd650 may not sound exactly the same anyway. I'm at no moment dismissing your hypothesis. I'm just saying keep the others in mind too as long as you can't rule them out.

I have a feeling there is more sample to sample variation than we would like to think (the idea of buying multiple versions of the same phone to find the "best one" could lead to insanity).  Audeze is accused of this quite a bit but it must happen with everybody to some extent.

sure. there is manufacturing precision that often leads to 1 or 2 db variations in some places simply between left and right drivers. so from pieces to pieces, in the long run, with maybe some molds being used a certain number of times before being replaced... plus in the case of audeze, a voluntary desire to keep evolving(which should never lead to models keeping the same name IMO, it can only become a trust issue for the consumer), certainly doesn't help the already hardcore precision needed for planars.
and of course, Senn not communicating on this does not prove they never made changes. I'm just trying to stay rational here, and not jump to conclusion when many other possibilities haven't been ruled out yet.

 

[iancraig10]

Perhaps it could be down to tolerances as well. In the case of the hd650, both cups are closely matched but if (within tolerances).....

A= treble biased
B = less treble focused

Then in the case of Senn, wer're going to get either

A+A = a treble biased Senn

Or

B+B = a less treble biased Senn.

Both types would be well matched.

(Plus the pad variances)..... And any variations between A and B drivers, all within factory tolerances.

 

[whirlwind]

  I'm tempted to try another amp with my HD6XX. 
Currently got the WA6-SE. Is there something you guys would especially recommend? OTL?`

There are many amps that work well with the HD650 and an OTL is without a doubt one of the better choices that you can make.