To anyone who got the Crazy Cellos during the Amazon 50% off deal:
OOTB the are boom boom boom with boosted low end. If you want to make them sound much better (low end much more balanced with the rest of the bands) follow these simple steps:
1. Remove the stainless nozzle screens using a sharp pointy object such as a sewing needle or diabetic lancet. The nozzle screens are glued on, so they cannot be reused.
2. On the side of the nozzle, you will see a vent. Poke something through this vent hole. It has to be very small, as the hole is 0.5mm. I used a 0.5mm drill bit. Anyways, when you stick something through the vent hole, you will pop off a small round white filter (similar to micropore tape). You may have to use tweezers to pull the little round filter out of the nozzle.
3. Once the white filter is removed, install NEW stainless nozzle screens (4.2mm or 4.3mm). You can find them on Aliexpress for $0.05-$0.10).
With this simple mod, these are really good dynamic driver IEMs. I would rate them on par with the TinAudio T2, except with a touch more sub bass extension (something that the T2 is missing).
The CC is also way more comfortable than the T2. And I love the included wide bore tips, and wish I could buy a bag full of them!
Enjoy!