To my ears, LCD 2 sounds drier compared to SE5 Ref or Ult. LCD 2's upper treble presence is not as clean as LCD 3's, so it doesn't have the liquidity of LCD 3 or SE5. In terms of brightness, yeah I would agree that both LCD 2 and LCD 3 sound a bit brighter and more transparent compared to SE5 ref or ult.
As far as Ref vs Ult
On certain songs, Ult sound brighter, while on certain songs, Ref is brighter. Or you can say they give you different type of brightness.
Bass: The bass is actually very very similar, with a little bit more presence on the ult. The ADSR, capacity and bass detail are very almost the same between the two. Ult definitely not bass light compared to Ref or to any of my other CIEMs. It's a bit on the right side of neutral.
Mid: The Ult is the winner here clearly for me. It's more refined with better coherence and placement. Everything sounds more accurate and more natural. Ref. in contrast can sound not as clean (or overly detailed) due to the huge hump at upper mid region. But as I posted long before, If are a hardcore fan of vocals, or if you want to use Ref for mainly vocal listening. Ref's coloration definitely gives the presentation of vocals one of a kind. Extremely smooth, sponge like. But for me “neutrality/naturalness” is more important. Plus all the amazing characteristics of the mid is still retained in Ult.
Treble: Ref has a big cut at lower treble region (~6-8k Hz) giving the overall presentation a lot of warmth and sound space (y and z direction), while Ult is linear in this region, giving rise to a better focus of the imaging, and more accurate staging presentation. With that said, Ult's lower treble is still not perfect. It has a touch of thinness and sharpness, due to the non-linearity tuning from 5-9k Hz. So sometimes, it can gives you a little bit feeling of "hotness (sharpness plus the warmth of the overall signature)" in the music. So that's why I said on some songs, Ult is brighter/sharper due to lower treble, while on some songs Ref is clearer due to the upper mid, but neither the brightness/sharpness or clarity is presented via correct means IMO. Both Ref and Ult have superb treble extension up to almost 20k Hz, with Ult being a little bit smoother. Transparency and resolution are similar too.
Overall, I still find Ult has more "rights" than "wrongs" compare to Ref. Ult is definitely the more neutral one to my ears. Does it worth the extra money? for me yes. But I won't be surprised people prefer Ref. better. Both are still organic and natural for sure. Also an important note here, for people getting Ult, specially if you coming from Ref-burned-in brain, give it Ult sometime, because Ult has less "wow" factor compared to Ref on the first listen. But over time, I am confident you will find Ult is just more correct in Almost every way.
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