I'm using earphones and headphones plugged in directly to my mobile phone all this while. Recently I decided to acquire another set of earphones and received advice that an additional device such as the FIIO DAC/amp is required to improve sound quality. Would like to seek advice and opinion if these FIIO devices will bring some difference to the sound and if yes, whether it's a subtle one or quite noticeable/big improvement.

Between these FIIO units, which one is considered to be best in delivering the highest sound quality in terms of clarity and detail? I have received recommendations and so far the KA13 and BTR3K are said to be good. What about KA3, is it really lacking behind the other two?

KA3
KA13
BTR3K

Any advice appreciated.

KA13 is the updated version of KA3, so if you are already considering KA13, then there is no point of thinking about KA3. (note, that's how FiiO names updated models, so KA13 is upgraded from KA3, KA11 is upgraded from KA1, etc).

BTR3K is decent but it is designed as a Bluetooth adapter first and a USB dongle second. It will be a good choice if you need a device that can works as both, but otherwise I generally won't recommend it as a pure USB dongle because eventually the battery inside will degrade in a few years.

Thanks for the response. that's good to know. I placed order for KA13 last week from Redape, delivery will be today. The KA13 looks better than the KA3 and is a newer design, and since the cost difference is just few ringgit, I chose the KA13.

The BTR3K was actually recommended for the Takstar 82 Pro that I own by somebody on the Head-fi forum as the best combination. However, I'm getting the FIIO for my new pair of IEMs and not for the Takstar headphones so it doesn't really matter. Also, I am not into bluetooth and good to know about the battery degradation issue with bluetooth DAC/amp devices.

Right. I just spent some time listening to the KA13 and my newly acquired IEMs yesterday, just 30 minutes as I don't have much time to listen anyway. I didn't compare listening to the IEMs with or without the FIIO KA13 so I can't really say if the additional device makes a difference. But I'm really happy with the new IEMs, the Simgot EA1000 which has proven to be an improvement to the EA500LM that I got about 2 months ago. The clarity, detail and particularly the cleaner and more defined bass are certainly a step up from the already good EA500LM.

I just got to know that the Elysian brand of IEM is actually designed and marketed by a Malaysian engineer when I researched on it, after someone recommended the Pilgrim. Perhaps I'll add the Pilgrim into my collection one day before I call it a day.