[gooeyrich]

Absolutely not. I had to EQ my 650's to make them brighter sounding. My 6XX I don't.

How do the frequency charts compare?

 

[descloud]

Possibilities of the HD6XX sounding different to the HD650 comes down to the following:

• Pad age
• Unit Variance
• Perception bias

Pad age is definitely the biggest change as Crin proved on his measurements. The older the pads, the darker/warmer the HD6XX/HD650 becomes. Unit variance is also possible, but I haven't seen reports of Sennheiser drivers having wildly different frequency curves for the same model unlike some Audeze and Hifiman models. With that said, I will label the second option as the lowest possibility.

Now, assuming you tested using the same fresh pads and still say the HD6XX is brighter sounding, I would attribute this to the likeliness of perception bias. This is similar to if you were doing wine tasting and know the price difference - more often than not there is this inherent perception of the more expensive one being "better" or "tasting different". There's a link that's been shared multiple times about this so I won't be re-linking that anymore.

To get to my point, if you initially tested the HD6XX with fresh pads and the HD650 with older pads, there would likely be this inherent perception that the HD6XX is brighter, and carry on even if you swap the pads on the HD650 to a fresh pads. At this point you have done sighted testing. Best way to remove this type of perception is either performing measurements using reasonably accurate equipment that will confirm or deny what you're hearing, or do a proper blind test with the two models.

Just my two cents on the matter. By far I haven't found evidence to support the HD6XX being different acoustically from the HD650. I welcome to be proven wrong though.

Actually I was incorrect a bit. This case I was mentioning wasn't exactly perception bias, but primacy effect. My bad guys

 

[thekenta]

After Drop hasn't put out the same good discount for the 6xx as last year, I decided to make my life easier and just purchase a pair of HD600.
Any reason why I shouldn't go for the new Romanian versions? I do prefer the look of the matte coating.

 

[Majestyk]

I like the look of the Romania but the Ireland has a bit more solid feel to it, IMO.

Just grab a new pair from a place where you can easily return them, if they're not to your liking.

 

[darkarn]

Thanks for the impressions and advice so far. Let's hope that all of us can get the HD 600 we want at the right prices and condition in this Black Friday / Cyber Monday!

 

[Kammerat Rebekka]

I’m willing to bet a pound of potatoes on the fact that the older marble-kitchen-counter design feels more sturdy simply because it looks like...well marble
I would be very surprised if Sennheiser suddenly decided to risk everything by fiddling about with the recipe for their plastic parts...and it would probably also be a very expensive procedure...and perhaps a tad nonsensical when they already have a formula that works for them.
The differences between old and new most likely stem from the new molds...not the material.

 

[gimmeheadroom]

I heard they even got the same molds when the Ireland line they were made on closed. Don't know if @Sennheiser will confirm or deny.

 

[Majestyk]

I’m willing to bet a pound of potatoes on the fact that the older marble-kitchen-counter design feels more sturdy simply because it looks like...well marble
I would be very surprised if Sennheiser suddenly decided to risk everything by fiddling about with the recipe for their plastic parts...and it would probably also be a very expensive procedure...and perhaps a tad nonsensical when they already have a formula that works for them.
The differences between old and new most likely stem from the new molds...not the material.

The Romania pair are lighter. There is no disputing my scale that I weighed the two on.

 

[Majestyk]

Go to 2:45



"It does feel lighter and a little thinner and cheaper than some of the other models."

I don't know what he means by 'other models' but I do agree with the lighter and cheaper feel. That said, I still like the look of them.

 

[Kammerat Rebekka]

So you want the potatoes

All I’m saying is that I think it’s down to the new molds...not because Sennheiser figured out a way to lessen the quality of material used (ie plastic).

 

[Majestyk]

I don't think they lessened it either (I think the looks make up for the SLIGHTLY cheaper build) but they did make them lighter to save money. Two years ago Sennheiser was set to discontinue the 650/600 for the 660S, but that fell through. Plus they've made so much money on those phones that any negative PR on the refresh ones (which there hasn't been) wouldn't have been overly worrisome for them.

 

[Kammerat Rebekka]

I honestly don’t know but maybe you’re right. To me it just seems odd fiddling around with a winning formular.
I always looked at the new molds as Sennheiser’s way of keeping up with the youngins aka make the design slightly more ‘fresh’ and ‘modern’...without alienating themselves from their older fan base who by now have built large temples in the HD600/650’s honour.
But yeah...they could of course be saving a bit of dough in the process

 

[CJG888]

Could it be that they’re using some carry-over frame parts from the 660S?

 

[Majestyk]

I'm not sure if the 660S parts are the same. I know they got the refresh treatment but I don't recall them being lighter. I used to have both a Romania and Ireland pair and it never leaped out at me that the Romania were lighter. I could be wrong because why else would they have given the refresh treatment for the 660S other than to save a little money? Anyway, I just bought another pair of 660S (on sale) so I will know soon.

 

[Deolum]

When your amp has 4 gain levels and the volume goes from 1-10 and you hear with the HD600 on the lowest gain level on volume 1/10. XLR really gave the last edge in terms of power lol.