[Tripokaridos]

your hearing is worse than a measurement rig's. A measurement rig isn't affected by emotion.

A proper measurement rig will always be more accurate giving graphs thats true , But Sound is not always about Graphs ... Human hearing is so complicated that there is no Digital equipment that can replicate exaclty what a human ear can hear , Thats why after calibrating sound systems with rigs there are pros that make some small corrections , in my opinion graphs are just a starting point thats it .
And honestly i have seen so many different meassurements for 600 ,650,660 that is hard to bealive what is correct or not, But again if a headphone sounds better for me then thats it ... The small differnces in all those graphs are so small that even a small movement or a small differential of pads and placement can make some difference , even the foasm used beetween the drivers some times is different , event the pressure of the air can make a difference and the heat .
So even if the meassurements are SPOT ON and perfect doesnt mean that the Closer to Harman the better a headphone will sound , some people like this target some dont . I am not saying that go far away from it but some small changes are not bad ...for some peope .

I use a lot both of them 650 and 660s so for me both are amazing , But again to my ears the Resolution , Speed, imaging, air between the instruments is better on 660s , and 650 are smoother more delicate on bad grainy recordings . And i dont need any rig to know that i can surely hear it clearly

 

[Ichos]

A proper measurement rig will always be more accurate giving graphs thats true , But Sound is not always about Graphs ... Human hearing is so complicated that there is no Digital equipment that can replicate exaclty what a human ear can hear , Thats why after calibrating sound systems with rigs there are pros that make some small corrections , in my opinion graphs are just a starting point thats it .
And honestly i have seen so many different meassurements for 600 ,650,660 that is hard to bealive what is correct or not, But again if a headphone sounds better for me then thats it ... The small differnces in all those graphs are so small that even a small movement or a small differential of pads and placement can make some difference , even the foasm used beetween the drivers some times is different , event the pressure of the air can make a difference and the heat .
So even if the meassurements are SPOT ON and perfect doesnt mean that the Closer to Harman the better a headphone will sound , some people like this target some dont . I am not saying that go far away from it but some small changes are not bad ...for some peope .

I use a lot both of them 650 and 660s so for me both are amazing , But again to my ears the Resolution , Speed, imaging, air between the instruments is better on 660s , and 650 are smoother more delicate on bad grainy recordings . And i dont need any rig to know that i can surely hear it clearly

On which one do you hear more extended bass? (reall bass not mid bass!)

 

[Tripokaridos]

On which one do you hear more extended bass? (reall bass not mid bass!)

My HD 650 has a bit softer pads i change them 6-8 months ago ,and the HD660s have newer pads not by much 3-4 months old .

At the shame tracks HD650 has more bass ( mid bass ) because my colection doesnt have a lot of sub bass , so i can hear most of the times more bass on HD650 , also it sounds like the bass on HD650 is how can i say it ??? slower ? like it hits and stays and bit more ...
HD660s also on the shame tracks the bass sounds closer to Sundara than HD650 , it has the warm character on highs but on bass its different to HD650 ( i will try to explain it corecty me if my english is bad) The bass on 660 has progression when it hits its like it has some layers before and after the hit , and on tracks that the bass hit constantly i can hear like the one bass note is seperated to the other bass note .
At the end Side by side when i give them to my Wife ( she has no idea about sound ) and asked her what do u think ? she told me that the one i can feel the bass more , and the other i can hear the bass notes cleaner ....

 

[Ichos]

Thank for sharing this!
I guess you are talking about one note bass and multilayered bass.
It is very easy to confuse one note bass as being more extended in quantity.
Something like when small bookshelf speakers arouse room modes and the user is listening to standing waves thinking that his system is doing proper bass....

 

[Tripokaridos]

Thank for sharing this!
I guess you are talking about one note bass and multilayered bass.
It is very easy to confuse one note bass as being more extended in quantity.

After using google translate lol.... Yeah this exactly what i am saying thanks .

But u already know that , after all those headphones reviews

 

[Dawgfish]

A proper measurement rig will always be more accurate giving graphs thats true , But Sound is not always about Graphs ... Human hearing is so complicated that there is no Digital equipment that can replicate exaclty what a human ear can hear , Thats why after calibrating sound systems with rigs there are pros that make some small corrections , in my opinion graphs are just a starting point thats it .
And honestly i have seen so many different meassurements for 600 ,650,660 that is hard to bealive what is correct or not, But again if a headphone sounds better for me then thats it ... The small differnces in all those graphs are so small that even a small movement or a small differential of pads and placement can make some difference , even the foasm used beetween the drivers some times is different , event the pressure of the air can make a difference and the heat .
So even if the meassurements are SPOT ON and perfect doesnt mean that the Closer to Harman the better a headphone will sound , some people like this target some dont . I am not saying that go far away from it but some small changes are not bad ...for some peope .

I use a lot both of them 650 and 660s so for me both are amazing , But again to my ears the Resolution , Speed, imaging, air between the instruments is better on 660s , and 650 are smoother more delicate on bad grainy recordings . And i dont need any rig to know that i can surely hear it clearly

That's a great summary, well thought out and presented. It's too bad that it will fall onto deaf ears with the measurement crowd however (pun intended). I've quit trying to reason with them. It's just a waste of time.

 

[enricoclaudio]

Well, the HD660S balanced cable right side connector just died. If I wiggle it, I get sound. I need to push it to the front for it to work. The SE cable works just fine. I already asked for a HD660S replacement from Amazon which will arrive tomorrow and this defective one is going back. These Sennheiser cables look very fragile. I have a few from Hart Sound on the way already.

 

[Duxxy]

Trying to figure out if Sennheiser sent me a bad refurbished unit. Do all 660's sound quieter in the middle than the left and right? Not sure how to describe it. It's like the left and right have the full range of sound, but the middle is noticeably "off" when I compare it to other headphones.

 

[Kammerat Rebekka]

^That sounds very strange tbh.
I was about to ask if you were coming from the 600/650 as a reference aka very used to neutral mids…because there are those folks who have been living with the 600 on their noggins for two decades..and when they finally hear a headphone with marginally lesser forward mids…it sounds off and/or like the mids have been pulled back.
…but I see that you also own the 58X so the difference should be the same methinks.

 

[Tripokaridos]

Well, the HD660S balanced cable right side connector just died. If I wiggle it, I get sound. I need to push it to the front for it to work. The SE cable works just fine. I already asked for a HD660S replacement from Amazon which will arrive tomorrow and this defective one is going back. These Sennheiser cables look very fragile. I have a few from Hart Sound on the way already.

Oh my sad to hear that , I hope everything will be ok and get your cable back ...personaly i never had problem with those cables , when i first saw those HD650 and 660 ( i think now the new 600 use the shame cables) i thought omg this looks cheap cable but the truth is way different after using them and moding them thats what i understand.

Stock Sennheiser doesnt look beautiful but...
1) they are light
2) they are not microphonic
3) they dont tangle
4) they dont keep their shape ( memory) also they are not stif
5)they are oxygen free copper with silicone protection ( i think i have post some photos way back when i mod them)
6)they are not braided that will look bad after years
7) the jack connector its rubber so its lighter , it doesnt hit the desk or make scratches everywhere , and doesnt lose the painting
8) the original 2 pin connectors are different than 90& of aftermarket ones ( there are many problems with 2 pin aftermarket that are longer or thicker so they destroy the inner conections
9) It doesnt interfere with any external frequencies like mobiles for example
10) they are easy to mod because when u cut the cable it can be soldered ( some others dont for example Meze stock cable from 99s)
11) they are easy to find and cost nothing ( the non balanced )

So yeah it doesnt look premium like my B&W , B&O cables but using it is better than the others.

 

[Tripokaridos]

Trying to figure out if Sennheiser sent me a bad refurbished unit. Do all 660's sound quieter in the middle than the left and right? Not sure how to describe it. It's like the left and right have the full range of sound, but the middle is noticeably "off" when I compare it to other headphones.

If i understand correct the sound is a bubble and u can hear the sides of the bubble louder than the center of the bubble ? If thats it ,then NO this must not happen ... and my HD6 line compare for example to HD599 has more center sound and the suround sounds are not so forward .

ANyways ... Try that before doing anything , open an open world video game something like PUBG or Ring of elysium that is free , and tell to a friend move around u in circles first close and then far ... the sound that u hear when is close to u must be the shame level and only the position will change ... If he moves around u at the shame distance and u hear different volume then Yeah there is some problem there ...
I would tell u to test some free online souround programs but i prefer games because there is also a lot of environment sounds like waves, birds, dust etch etch ... so its better .

I make a stupid sketch to show u how it must works on HD 660s vs something like HD599 .

 

[Dawgfish]

Trying to figure out if Sennheiser sent me a bad refurbished unit. Do all 660's sound quieter in the middle than the left and right? Not sure how to describe it. It's like the left and right have the full range of sound, but the middle is noticeably "off" when I compare it to other headphones.

If you are referring to center image than no I haven't experienced that at all. In my experience with the 660 it has a strong center image.

Check your connections both at the headphone and the source. Also try different sources/amps and different types of music. If you have any interconnects in the audio chain make sure the connections are secure and working properly. Also try a different cable if you have one available (try the cable from your 58Xs).

 

[SchwizzelKick66]

Trying to figure out if Sennheiser sent me a bad refurbished unit. Do all 660's sound quieter in the middle than the left and right? Not sure how to describe it. It's like the left and right have the full range of sound, but the middle is noticeably "off" when I compare it to other headphones.

Doesn't sound right to me. There is a clear center image on my 660s. In comparison to the 58x and 6xx, the soundstage is much more well blended. The 58x and 6xx have that "3-blob" imaging of center, then hard left and right, while the 660s doesn't suffer from the same. So while the center image isn't as well defined as on the 58x and 6xx, it's still present.

Have you tried swapping cables?

 

[Duxxy]

Yeah, I've tried multiple cables. There's a noticeable difference between the 660s and my other 6 series headphones (I have them all).

I think I have a dud. Thanks all.

 

[SchwizzelKick66]

Dang that really sucks. You could try contacting Sennheiser to see if you can send them in for repair, though I'm not sure how much they will charge if its out of warranty.

The 660s are indeed different than the other 6 series, they soundstage and image quite differently. But the center image issue you explained is strange, not sure if its normal. I guess it could be that your ears just don't jive with them lol.