After several months now of comparing the Universe and Ultra perf Caldera pads, here is the time to give you some new thoughts. First of all, thanks to Zach for his video tutorial on pad rolling.... If at first it took me 5 minutes, I can now compete with him in a speed contest 
I compared these 2 types of pads by changing them every month. This allowed me to better appreciate their qualities and faults. I mainly listen to music while working from home and I am 56 years old. My listening sessions can be very long, sometimes 5 to 6 hours a day. In these long sessions, the Universes take the advantage. Less hearing fatigue, better concentration (Universes narrow the sound space). The Utra Perfs are more distracting and the feeling at the treble level is more tiring (but this problem of sensitivity to treble remains personal, I already had some difficulties with the Utopia).
In terms of resolution and soundstage, I agree with most of you, it's better with the Ultra Perfs but we have to put things into perspective. This resolution benefits the treble and not the midrange and bass. The instruments are better detached, spaced out, identified. The voices, on the other hand, are in the background. It's fine if the musical composition is superior to the vocal performance, but otherwise, no. The other problem remains the stage height. The ultra perfs flatten the scene by accentuating the stereo effect. But the height of the stage and the musical mix become more neutral, less grandiose than with the Universes. I initially agreed with one of our members who said that with the Ultra Perfs, the Atrium became even more Atrium. But if we start with the cathedral effect (also designed for the atrium), the Universes are superior. The sound is higher, resonates more in 3D. Finally, the least well recorded albums (often older) sound better with Universe. Often remastering focuses on the musical composition, less on the vocals. The result is that the voice no longer has the necessary warmth that the Universe can give them. Last thing and not least, the discovery of albums and the feeling of surprise. Universes are more surprising in the sense that the appearance of an instrument, vocal effect or reverb is original and unique. If we save the best for last, that is to say as far as I am concerned, the bass, its rumble, the veracity of an instrument, there again, the Universes are the strongest. So what to choose? At the moment none, it can sometimes be nice to extend the stereo with the Ultra Perfs. But on a daily basis, to be in the music and feel things viscerally, the Universes remain the best in my opinion.
I compared these 2 types of pads by changing them every month. This allowed me to better appreciate their qualities and faults. I mainly listen to music while working from home and I am 56 years old. My listening sessions can be very long, sometimes 5 to 6 hours a day. In these long sessions, the Universes take the advantage. Less hearing fatigue, better concentration (Universes narrow the sound space). The Utra Perfs are more distracting and the feeling at the treble level is more tiring (but this problem of sensitivity to treble remains personal, I already had some difficulties with the Utopia).
In terms of resolution and soundstage, I agree with most of you, it's better with the Ultra Perfs but we have to put things into perspective. This resolution benefits the treble and not the midrange and bass. The instruments are better detached, spaced out, identified. The voices, on the other hand, are in the background. It's fine if the musical composition is superior to the vocal performance, but otherwise, no. The other problem remains the stage height. The ultra perfs flatten the scene by accentuating the stereo effect. But the height of the stage and the musical mix become more neutral, less grandiose than with the Universes. I initially agreed with one of our members who said that with the Ultra Perfs, the Atrium became even more Atrium. But if we start with the cathedral effect (also designed for the atrium), the Universes are superior. The sound is higher, resonates more in 3D. Finally, the least well recorded albums (often older) sound better with Universe. Often remastering focuses on the musical composition, less on the vocals. The result is that the voice no longer has the necessary warmth that the Universe can give them. Last thing and not least, the discovery of albums and the feeling of surprise. Universes are more surprising in the sense that the appearance of an instrument, vocal effect or reverb is original and unique. If we save the best for last, that is to say as far as I am concerned, the bass, its rumble, the veracity of an instrument, there again, the Universes are the strongest. So what to choose? At the moment none, it can sometimes be nice to extend the stereo with the Ultra Perfs. But on a daily basis, to be in the music and feel things viscerally, the Universes remain the best in my opinion.