“Let me preface this review by first letting you understand where I come from as I think that will give you some valuable perspective of my thoughts and opinions about this little gem. This also probably won't be a conventional review in that I describe in detail about the sound signature but I will make clear and efficient comparisons to well known IEMs. So I am a music producer and...” --Marc Lian
“This is in my humble oppinion the very best bang for your buck custom in ear monitor on the whole market. For 250 british pounds you get a very nice piece of equipment, from very nice people too! The guys at cosmic ears care about their stuff being done properly and on time, they checked everything to be correct, from my ear canal impressions to colour, logos, letters, etc. They also come with...” --ardacer
“First of all I'd like to say the customs and the cable are both insane, the customs look incredible and the linum cable and connector beat the hell out of any other CIEM I've seen around. Cosmic Ears list this as a jack of all trades monitor which I do agree with. I'm coming from a 4BA model to this 2BA and I've been pleasantly surprised by the sound. I haven't had these a week yet so...” --daftpolecat
“First of all I'd like to say the customs and the cable are both insane, the customs look incredible and the linum cable and connector beat the hell out of any other CIEM I've seen around. Cosmic Ears list this as a jack of all trades monitor which I do agree with. I'm coming for a 4BA model to this 2BA and I've been pleasantly surprised by the sound. I haven't had these a week yet so...” --daftpolecat
“Copied from: http://www.head-fi.org/t/686039/cosmic-ears-ba4f-review I'm finding it hard to rate these, for the price I would give them 5 stars on every department. But I'd rather rate them, referenced with the idea of what the very best cIEM could be. The BA4f with the Ice Blue color Short History Before I started my journey into the cIEM...” --Marleybob217
“The HY3 is a three-way, three-driver hybrid custom in-ear monitor from Sweden-based Cosmic Ears. It utilizes a dynamic driver for the bass and twin balanced armature drivers for the midrange and treble, which used to be a very rare configuration, although hybrids have increased in popularity over the past year. The bass unit looks to be around 8mm in diameter and has its own sound bore. The two...” --blueangel2323
“A mids-focused specialist with a little bass thump and smooth, relaxed treble (recessed, but still has some detail). Not an especially engaging sound (a little too relaxed maybe). Decent across genres, but tend to congestion during busy/noisy passages. I find them particularly useful for low volume podcast legibility, though with podcasts that are poorly leveled, subject to intrusive volume...” --Raketen
The HY2 combines a dynamic driver for lows and a balanced armature for the mids and highs. This dynamic driver also delivers an increased soundstage. The HY2 is a great sounding monitor for those looking for something a little different by combing the 2 driver technologies. Twin hybrid – 1 for lows, 1 for mids and highs Full sized medical grade hard acrylic shell Various...