REVISED ENTIRE WRITE-UP.
ADDED NEW HEADPHONES TODAY:
[IE8 PICTURE COMING]
Fake Sennheiser IE8 ($27 from aliexpress.com)
FAILED at higher volumes, but passed up to near my loudness threshold.
Bass timbre: "TUUD"
Recommended for normal listeners.
If I had $400 I'd get the Sennheiser IE80. I recently got my fake IE8 (I bought them knowing they're fake) and I was pleasantly surprised how genuine they look when put to the authenticity test (especially the red wires and the bass dial). Even the sound signature is spot-on. They sound close to my authentic Sennheisers, but not quite at the dangerous volumes I normally listen to. They could've fooled me for sure.
[SL99 PICTURE COMING]
SL99 by Ludacris ($49.90 from staples)
PASSED beyond loudness threshold.
Bass timbre: "TOUG"
Recommended for some bassheads who like that bass sound.
Before I added the SL99 to this list, I concluded that the Klipsch S4 is number one on my to-buy list. Since I love challenging convenient notions such as that celebrity endorsed products are bound to be poor, and due to the raving reviews at bestbuy.com swearing that they're better than the Klipsch S4, I decided to keep an eye on the SL99. Suddenly, the SL99 was put on clearance for half the price so I bit. I also love Ludacris.
The timbre of the bass is not deep at all. While the top of my list, the CXL400, sounds like a large, deep "TUUD", the SL99 sounds like "TOUG". The "TUUD" sound is a controlled low frequency response that is maintained at higher intensities, while the "TOUG" sound is a bloated mid-bass. It is however capable of driving that bass sound beyond my loudness threshold. But I don't really like that bass tone quality. And I agree that the SL99 keeps the mid and high frequency details intact just like the CX400.
The WORST thing about the SL99 surprised me: The metal mesh that covers the tube came off easily! You'd think it was built like a full metal weapon of war but no; I simply tried changing the buds from medium to small--WHICH WAS HARD TO DO BECAUSE THE TUBES WERE RATHER THICK as if someone was trying to insinuate something--and when I removed the rubber tip the tip rubbed the mesh and came off with it. The metal mesh was so thin as well.
It is worth noting even if it is readily deducible from the previous paragraph that the fit hurts like rape.
The FX101 and the SL99 sound similar at higher volumes, and this is possibly because of the vents. But if I cover the vents on the SL99 I get a deeper bass sound while the FX101 crackles when covered. The FX101 however has a superior fit.