I’m convinced the engineers in Germany are still locked in a room with a single HD650, using it as the holy grail. It’s the ultimate German joke: "How many Sennheiser engineers does it take to change a lightbulb? None, the HD650 already perfected the darkness 20 years ago." Even the 560S feels like it’s just desperately trying to sniff that 650 DNA.

The 660S and S2? They never stood a chance. It’s hard to sell a "sequel" when the original is already the final boss. They’re basically paying more for a "different" sound that nobody asked for while the 650 just sits there laughing.

Now, the IEMs are where it gets truly weird:  
**IE 600:** I don’t know what they were smoking, but this ain’t it. The tuning and imaging are so far off from what our ears are actually "trained" to hear as natural. It feels alien—like it’s trying to reinvent physics and failing. It’s fighting my auditory muscle memory.

**IE 900:** This one is just a technical flex for the sake of it. It’s like those over-hyped "Instagram-famous" bakeries. People line up for miles just for one specific, flashy pastry. Sure, you get that "hit" of resolution, but it’s so aggressive that it drowns out the actual music and the vibe. It’s a total "Sunk Cost Fallacy" flagship—loads of detail, zero harmony.

If it doesn’t have that 650 soul, it’s not a real Sennheiser. It’s just expensive jewelry.

Let’s be real, the HD650 is the only "Sennheiser" sound left. Everything else is just a side quest.