The sound signature is near neutral but with a little emphasis on the lower frequencies. The bass is slightly forward with good punch and tightness. Explosions will have good rumble, without overpowering the other frequencies.
The mids are warm and clear, adding extra body to the sound. Game dialogue will be easy to hear.
Highs have good clarity, but are not forward in any way, so harshness is minimized.
The open ear cup design allows the sound to blend with your surroundings, giving it a natural width. It will also be easier to identify the direction of sounds, which can really help immersion.
Clamping force is not too tight. The ear pads and headband feature memory foam which are covered by velour material. The pads feel really soft on the head and allow airflow for minimized heat build-up/sweat.
The headband also features similar cushioning materials and minimizes pressure spots on the head.
The HD-650s do not feel heavy at all. They are usable for long music listening, movie or gaming sessions without feeling pain or strain on their head and neck.
While the cable connectors are proprietary, they can easily be removed from the ear cups with a firm pull. The popularity of these headphones means that there are a lot of aftermarket cables that can be bought.
Plugging these directly to your computer or phone will most likely result in audio that is lacking in volume or may sound too thin. To get the best listening experience, you will need to run these with a capable headphone amp.
The open design means that a lot of sound can leak out the ear cups. Other people in your immediate vicinity will be able to hear your music, movie or game, which can be annoying for them.
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.
The HD 800S has one of the widest sound stages of any pair of headphone today. There is excellent separation between in-game sound sources and you can easily identify where various audio effects are coming from.
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.
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.
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.
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.
These headphones are quite power hungry and will not produce optimal sound or volume when plugged directly to your phone or laptop. You will need to invest in a separate, fairly powerful amp to get the best sound out of these.
Only a very fine mesh piece covers the large headphone drivers from the outside. These are basically mini speakers so others can easily hear what you are listening to.
Your choice of amp and DAC can have a noticeable effect on the sound of the HD 800S. You may need to do extra research as to which audio equipment can bring out the best sound from these.
The HE1000 V2 requires a pretty long burn-in time of around 200 hours in order to get the best sound out of it. Initially, the highs can be harsh and the bass a bit lean. After burn-in, these issues should not be present anymore.
These require a bit of power to run so you will most likely need to invest in a great amp. Also, you may want to consider going through different DAC options as these headphones are so revealing that you can easily distinguish artifacts or distortion from a lesser performing DAC.
Despite weighing less than the V1 version, these V2s still come in at around 420 g. This is quite a weight to put on to your head and neck for extended periods so you may need to take the headphones off periodically.
The sides of these earcups are almost totally open so when you play music through these headphones, they also function like mini speakers as they leak out a lot of sound. These are not the best headphones for you if you share your room with other people as the sound can be distracting.
Highs are really clear and crisp and are able to present even the slightest details in the music that other high quality headphones are not able to give. These frequencies have a lot of sparkle and airiness to them, yet do not sound too harsh or too forward, preventing these from sounding fatiguing.
The mids are mixed really well with the rest of the frequencies. Slightly forward, the mids can easily be heard and appreciated, so sounds like vocals, guitars and keys are really defined.
The bass of these headphones have good power, but not as much as bass-heavy "bass head" cans. Instead, the bass is natural with good sub-bass presence. Bass thump is definitely there but without the bloat that can muddy up the sound.
It comes with 3 different headphone cables, with each one terminating in a different connector. This gives you a lot of versatility in terms of the audio sources that you can connect to. They also work well as spare cables should one get damaged.
It comes with a balanced XLR cable, a 6.5mm TRS cable which are best suited for desktop use and a 3.5mm cable for portable devices.
The sides of these headphones are covered by metal grills which makes the earcups really open. This gives the sound a wide feel, which can be very immersive.
Memory foam is used inside the ear pads, along with a leather/polyester combo on to the surface. Combined, the pads feel ultra soft and smooth on the skin. This also contributes to the headphones' overall premium look and feel.