My initial impression was quite negative. I really thought it was a mistake to buy these in ear headphones however, I decided that coming from regular use of AKG K712 this set the high bar for my expectations. I decided to give them a chance and let them burn in for a while. I also, explored the fit and I believe that the proper fit is the crucial element of making these headphone work. It is important to select the ear tip that fits best in the ear from the provided sizes. Also, the position and depth in the ear plays important role in how the sound reaches the internals of ear.Once they fit the sound is great. The bass is a bit deeper than what I am used to but is not offensive - it is clear and full without distortions. The mid frequencies are not as pronounced but overall this is what should be expected given these are - Solid Bass. I have listened to classical, rock, metal, electronic etc and I am finding that these headphones deliver on promise with every type of music. They make the good recordings sound better and the not so good become obviously worse. Given some time to get used to the in-ear feel and the headphones frequency response I am finding them to be very satisfying and worth the price. For those who have doubts after the first listen please, do not give up and be patient - give them a chance they deserve.I have another IEM for music. If i was picking this one for that I would probably give it 2-3 stars. It has a very limited range and everything but the lows and impact are unspectacular. Not Audio Technica's best work.However, I use these for video games and they are excellent. I know IEM's aren't the typical first choice for video games, but if that's what your'e looking for (as I was), these are actually pretty good. There are few IEM's that can hit with impact like these, and this can be quite nice when playing a game. They've certainly got some oomph. But, that's where the highlights of this product kind of end.I give it 4 stars with the caveat that I use it for video games and I bought it used for under $100.These buds slowly became my favorite pair. Took a few weeks for the sound to ripen. I have a pair of the MSR7s that were my daily drivers till these burned in.The bass is tight and expressive, the mids sound clear and the highend sounds decent as well. Before they were fully burned in they did not sound so great, mostly bass with poor mids and highs and the burn in took a lot longer than normal. There were a few tracks I noticed some riffs in the midrange were impossible to hear, not from too much bass, just non existent. Believe me, the sound after a few weeks was like night and day.The build quality is nice and the case is great, it makes up for being cheap feeling with it's easy access.Sadly I broke them recently, no fault of the build. In fact, I am impressed that they didn't break sooner with how many times I caught them on stuff I was walking by. I break earbuds constantly doing that. I am upgrading to the cks1100is because of how great these were.Overall, after a long burn in for the drivers, these are the best in ears I have.So first thing first, the bass. These things actually have pretty good bass, nothing super crazy but over my other earbuds these definitely have more bass. One thing to note is that these things are big, they have 13mm drivers which translates to being pretty large, however they don't bother my ears as much as I was worried they would. Once you get them in they sit fairly comfortably but they will stick out of your ear quite a bit so no laying down on one side unfortunately. My only reason for dropping a star is that at first when I tried them they sounded very shrill, the highs were very high and almost hurt my ears, however after burning them in for a few days they got a bit better. It's still noticeable if I turn the volume up high but it's not as bad. Currently use them as my daily driver and am very pleased with my purchaseFor the price I paid, these are good general use headphones for music listening if your willing to make a tradeoff in one area. These produce good tight low end that is appropriate to the music and can reach down surprisingly low while leaving the rest of music uncolored. This is their greatest strength along with a decent high end. However the trade off with this model is that the sound field is narrow, so it lets you know your listening to in ear monitors. Whereas, my pair of grado in ear monitors have a wide expansive sound field that allows me to sonically locate musicians especially during a live performance. I would NOT recommend these audio Technicas for classical, jazz or any music that is recorded live, you will be disappointed by the narrow and tight sound field.Very good sound quality and are fairly comfy after a while of wearing. However, they earpieces are extremely large and stick out of my ear about 2-3 inches which looks ridiculous. The wire is also very unwieldy and stiff which makes moving with the headphones in difficult and uncomfortable. I don't recommend buying these headphones as you would be much better off buying a different pair from brands such as Senheiser or Sony. The packaging that they come in is also very cheap and feels like poor quality plastic.Uso com um DAC (dragonfly/red) portatil no meu S20fe. O som é muito bom com ótimos graves (textura e definicao) e médios/graves satisfatórios pra um in-ear. Certamente não vai decepcionar. Esse equipamento só deixa a desejar no conforto e ajuste, ele não passa a sensação de segurança de que está bem fixo no canal auditivo, embora venha com várias ponteiras nenhuma oferece o ajuste perfeito...em outras palavras, essa falta de ajuste não é exagerada, só não é perfeita - aceitável. Mas se você precisa pra correr, talvez não seja o ideal.A qualidade do material é ótima e a case é pequena e bem acabada.Uma aquisição que não me arrependo.I got these CKS1100iS hoping for an upgrade in sound with the same comfort that I had with the CKS990, but unfortunately, the CKS1100's shape is somehow much worse than the CKS990 despite being pricier.For one, the CKS1100 is missing the rubber band around the circular part beside the ear tip which the cheaper CKS990 has. In other words, with the CKS1100 you're going directly on hard plastic on the pricier model for some reason.But that's not the worst part. The worst part is that the sound nozzle of the CKS1100 is less angled than the CKS990 nozzle. You would think this wouldn't make much of a difference, but it makes such a massive difference it's not even funny.Because the nozzle is more perpendicular to the rest of the earbud on the CKS1100, when you stick it into your ears, the corners on the back wings which didn't get in the way on the CKS990 now stab into your outer ear because they're turned more inwards due to the nozzle angle.It doesn't matter how you put the earbud into your ear, it jabs the wings into your outer ear and starts hurting in a matter of seconds.The sound on the CKS1100 is great and I really wish I could love it, but the angle of the nozzle absolutely ruined this earbud for me. I know fit is subjective and I've seen a few people online say they love these earbuds so your mileage may vary, but it irks me so much that the CKS1100 is such a bad fit for me when the cheaper CKS990 fit me perfectly.These IEMs sound really good IF AND ONLY IF you get the right seal. Because of the housing's huge size, a good fit can be difficult.However, if you do manage to find the perfect fit, the sound will be extremely well worth it. The bass on these are monstrous, like mini subwoofers in your ear, but they don't take any detail away from the mids and highs. The sound signature really favours Hip-hop and EDM, but I found other genres to sound good as well. To increase comfort and get a better fit, I recommend putting the ear-tips in the "deep" position (instructions on the box). This position keeps the housing further away from your ear, so it's less likely to make your ear sore from coming into contact with it. Something I found really annoying is the cable. It is super prone to tangling. All in all, I think these were a good buy. If huge bass with clear sound is what you want, these deliver.SHORT VERSION:Getting the right fit with these is difficult, but when you do, the sound is extremely worth it. Huge bass, but the sound is still very clear. The cable is prone to tangling, and it could be better. Overall, worth it.I was apprehensive switching from my Klipsch R6i, the best earphones I've ever had .... Until now.I listen to blues, rock and metal and need good low end thump, without overwhelming the mid or highs. Most earphones need a compromise on at least one of these parameters.These earphones take a while to get the right fit - nobody does fit better than klipsch! - but once you find the right tip size for your ears, the noise isolation is pretty good.The moment I turned these on, I was blown away by the incredible tonal width. Bass has real solid muscle without reverberating; mids and treble open up spectacular clarity.The only crib is that the soundstage feels limited - but overall fantastic value for money