I’ve been using my Cayin iHA-6 since March 2019. I have it paired with an RME ADI-2 DAC. The overall build is fantastic, it’s very heavy and beautiful. The sound of the relays clicking when you press the buttons inspires confidence. It feels very quality.
I primarily use the 4 pin balanced stereo XLR out, but do use 1/4" (low) out on some occasions. My impressions so far, is that pairing it with the right set of cans is crucial. For example, it is wonderful with my Audio Technica ADX5000, HD650’s, but to my ears doesn’t play as well with my Audeze LCD-X. I find that the bass extension, as well as some of the upper midrange detail is better when plugging LCD-X’s directly into the onboard amp on the RME. My suspicion is that this is due to a higher than average output impedance on the Cayin. That being said, SendyAudio Aiva’s sound fantastic as Modhouse Argons and others. The tone of the amp is clean, and slightly warm. On low gain setting there is never audible noise with any cans that I use, and low gain is enough to drive 95% of what’s out there. High gain on the other hand is a different story. I would only advise for very hard to drive cans, as I have trouble making it past 35% volume with anything i’ve tried (in balanced mode). The high current setting is useful for planars. It does something to do the sound for sure. I’ve used it with dynamic cans on and off, tends to warm them up but I leave off generally.
Overall I’m very happy that I purchased this amp. It’s a fantastic option for anyone wanting a high quality, very versatile amp to drive higher end, balanced, or hard to drive cans. It’s capable of delivering some serious authority, and looking fantastic doing it.