Shure SE215 vs Sennheiser HD 800S

Bass is emphasized so there is a good bit of thump while staying controlled. Mids are rich, highs avoid sibilance, though they're a bit rolled off.
Soundstage is okay--instruments are separated out enough for them to not sound like they're all coming from the same place, but it's not particularly wide.

The memory foam eartips mold to your ear to provide amazing sound isolation, though there's a bit of a learning curve to using them. You have to press them together before putting them in and then allow them to expand in your ear. Once expanded they will take the shape of your ear and that way provide excellent noise isolation.

The earphones also come with silicon tips which are easier to use than the foam ones and also last longer.

The SE215 earphones have a negative profile, optimized nozzle angle, over-ear fit and memory eartips that ensure the earphones stay in place comfortably regardless of situation. You can even lie on your side with them.

6 types of plugs (silicon/ foam: S/M/L).

SE215 earbuds use tough plastic earpiece shells, have a robust kevlar-reinforced cable, a sturdy Y-splitter that's difficult to bend and an L-shaped plug that adds additional strain relief. They won't break if you snag them, drop them or sit on them. They're also completely sweat proof so you can use them while working out without having to worry about damaging them. They're durable enough for professional stage use for which they were specifically designed for.

The SE215's 6.4-ft. cable is very thick, and further reinforced at the left/right split point. Reviews confirm the durability benefits of its heavy-duty design. If it ever does break, the cable is built to detach safely from the earpieces, allowing replacement.

The optimized angle of the earbuds, over-ear fit, and memory ear tips ensure that the earphones stay in place comfortably regardless of situation. These are also sweat-proof, so they're a great option for active use.

Shure provides a warranty against defects in materials or manufacturing for two years.

The highs are very clear and revealing, so you will be able to hear even the minute details from the audio that you simply will not be able to pick up with lesser headphones.

The mids are also clear and have nice warmth. They are slightly recessed, yet voices and mid range tones will come out full, so the sound is not lean in any way.

The bass is not boomy but still has enough power for a satisfying thump. Also, due to the bass' tightness and speed, there is no bloat from the lower frequencies.

These headphones sound very immersive. Aside from the highly detailed sound and powerful yet tight bass, the soundstage is very wide, which only a few headphones can match , if any at all.

Despite the massive size of the headphones, Sennheiser was able to keep the weight down by using a special material called Leona, which is very light yet has metal-like toughness.

The HD 800S has one of the widest sound stages of any headphone today. There is excellent separation and you can easily identify where various sounds are coming from and can be very immersive.

These headphones do not make unnecessary creaks or flex when moved or held. Aside from the use of Leona on the ear cups and headband, the size adjuster is made of lightweight metal, with fine yet durable stainless steel mesh covering the drivers.

Out of the box, you get a balanced XLR cable and an unbalanced TRS cable. If you have a balanced headphone amp, then the XLR cable will allow you to maximize your amp's performance with these headphones without the need to buy a different (and expensive) cable.

The ear pads feature high quality memory foam as cushions with the surface being premium quality velours. This material combo is also used on the headband. They feel really soft and conform to the contours of your head. Due to the fabric material, some air can move through the pads, minimizing heat and sweatiness.