Got the RE-ZERO yesterday, purchased off another member on the forum. I do see you and others comparing the two as being quite a alike still. While I haven't owned the RE0 for nearly two years, from my memory the RE-ZERO sounds very unlike the RE0 in many ways. While I get a sense that both are geared towards the same goals, I think the driver and note presentation is a sizable departure. It's certainly not RE252 different, but the RE-ZERO driver does seem to be a partial departure from the RE0 driver. One specific repeat I see from the RE0/ZERO line is a very heavily controlled driver is used. The benefit of this is that they offer some of the cleaner, lowest distortion sound from a dynamic most of us will hear. It is super clean and also handles complex information really well. It pretty much isn't allowed to get messy. There is a trade-off though, and it's one thing I disliked a good bit with the RE0. The high control comes at the price of limiting how freely the diaphragm moves. If anything happens, it's done through motor force. You end up losing some articulation, some dynamic breadth, some sense of effortless energy. What impact or texture that does show through seems forced. As well, high control means the low end frequencies end up a bit light. Even though this is a low ohm version, it still is happy to use up a bit of wattage from my Meier 2Move, more than I'd expect from a driver that's geared to be easy to run. I do feel it's within a range that is suitable for portable players and a moderate deviation the RE0, but it still shows that the design still requires power to equate to output and also power and output to equate to dynamics and raw energy. An inverse of this design would be the Denon C700/C751. The Denon follows the approach of creating a very loose, effortless driver. Dynamic breadth comes out more effortlessly without needing to be forcefully driven. Articulation and fine detail show through more readily and in this improved sound stage. The downside is that the diaphragm is considerably less controlled, and the sound can get a bit distorted or messy. The low frequency range of the Denon is a good example of what poor control can mean. Output gets very muddy and incoherent at volume. The Denon is really good for critical, quiet listening. The RE0 or RE-ZERO is happier at moderate volume. I think both of these products highlight the extremes of design while most dynamically driven earphones fall more in between these two. The RE252 for example is an in between product that offers a more expected presentation. The RE0/ZERO provides a unique setup that isn't really found in other dynamically driven products. I know my favoritism lies outside the range of the RE0/ZERO, but I do think the RE-ZERO is a step towards offering more to everyone while retaining that type of package than the RE0. The dynamics are improved and shows a better sense of subtlety and range. Sound stage is more specific with a greater sense of a sound existing in a point in space (RE0 was pretty sucky from my recollection). The tone is more natural or slightly bright at volume and a departure from the slightly dark sense of the RE0. I always thought there was some harshness in the highs of the RE0 and a slight inability to accurately articulate high frequency information. I see the RE-ZERO as improved with a more refined albeit maybe not as edgy top end. Even though my recollection of the RE0 is a couple years tarnished, I do like the direction the RE-ZERO is heading. I do see great value in the $80/$100 price points of these products. I do think the RE-ZERO is a step up in terms of mainstream appeal.
You know what I'd like to see? I like the RE-ZERO driver design. However the major limitation is low frequency "looseness." I would love to see a dual driver setup like the Radius DDM incorporating a version of the RE-ZERO driver as the mid-high and paired with a large bass driver. Because of the driver setup, there really is no way to get the presence and fullness on the low end, not even with EQing or an excess of wattage. The fix is dual drivers. It's something I'd be curious to see.
