Originally Posted by tinyman392
There is a lot less bass response in the UE 900 compared to the Triple-Fi. I don't know what drivers are specifically used in the Triple-Fi, but I'm sure it's 1 bass driver is far larger than the 2 in the 900 combined. It's probably a similar deal parallel to the 4.Ai vs 3.Ai bass quantity where the shear size of the 3.Ai bass driver makes the bass so much bigger than the 4.Ai which has 2 bass drivers.
The bass drivers used the the UE900 and TF10 are actually quite similar. The DTEC and 3300 are basically analogues of each other. The 3300 maybe has a bit more back volume for a more visceral bass impact, but the increased felt bass of the TF10 compared to the UE900 is most certainly due to the tonal balance between the lows and the highs, with additional alteration due to the chamber/pinhole design of the UE900.
This is not the same situation as the 3.Ai vs. 4.Ai; the 3.Ai uses a CI driver, which, along with the Sonion 2015, has the largest back volume excursion of any balanced armature driver around. The CI is an "ancient" BA driver, designed initially for massive SPL output (peaking at >140 dB). With effective low pass and damping, it makes for a "punchy" and "meaty" bass driver. It also tends to impart warmth to the midrange (yes, it goes all the way up there because all BA drivers are "full range"; the 1964-V3 uses a CI for its mid, mid/lows, as well as another CI/2015 for its absolute lows).