5K Bluetooth USB DAC AMP with LDAC, aptX Adaptive, aptX HD, AAC (Dual ES9219 3.5mm Unbalanced & 2.5mm Balanced Output)

I had high expectations and this device exceeded them. I have had 0 problems with the bluetooth connections between my phone and this device and the sound quality is exceptional. I want to emphasize how much better the sound is than other bluetooth adapters I have used. It is absolutely noticeable. I primarily use it to connect my phone to my older vehicle via a 3.5mm cable and to use my older wired headphones. I honestly can't tell the difference between using this adapter and plugging directly into a sound source.Build quality is excellent. I have a hard time imagining something breaking on this. It's just the right size so that it's not going to easily get lost, but it's small enough that it can fit in any pocket or clip onto a piece of clothing and not fall off.The app took a little work to set up, but once I got it working, I was impressed by the number of options and information available. I also haven't had any connection issues with the app since I set it up.This was well worth the cost for me and I heartily recommend it to others.

I came from the Fiio BTR7 which was usually crowned as the absolute best portable bluetooth dac amp that money can buy. It packed quite a punch of power for how small it was. unfortunately thats its biggest selling point. As the battery degraded to the point that it needs to be permanent plugged in to actually work and function. The firmware and software are genuinely awful, Unable to even just play music without the start of the song fadinh in and their seemingly being no actual way to fix it. And dont even get me started on the user repairability being absolutely nonexistent with the fact that the 2 backs are glued glass, So you at the bare minimum need a heat gun just to even get the glass off. which why not buy a new one at that point? You might be asking yourself "Ok, Why does this matter?" and thats a great question!The Btr7 is 200$, Meanwhile this Qudelix-5k is 100$, Has AMAZING software, Packs a good enough punch to use pratically any reasonable headphone with it. AND, is even more repairable than the Btr7. Sure, It doesnt have an Oled screen like the btr7, But does it need one? I mean a screen takes power yknow. and every watt of power possible should go straight to making sure the device can be what it was intended to be, a bluetooth dac amp that works as just that. Simplicity is better.Iv been using this with my brand new sennheiser Hd560S and it works like a charm and gets even very loud if I want it to be loud. Did I also mention the software? you can have individual EQ profile's for whatever device you are using. Built directly into the the device itself through its app. Lemme tell you, It works alot better and was far easier loading a profile than the janky setup I had for my android. which also caused lots of popping and distortion. But not here!That means the clarity of what im listening to is very very very clear to the source media and I dont have to worry about if the device itself is gonna do weird things to the audio and mess with it in ways I may not intend for it to mess with. Unlike the Brt7 which does the exact oppisate and even allows me to have fine control over what I might wanna hear from the EQ. instead of some vague preset options that I have no idea what they are doing to the audio itself.Its time to talk about the actual design and it is very thoughtfully designed. It actually feels like it was made with the intended purpose of being used by actual real people and not for the sole purpose of looking cool. to think that a 100$ device can somehow someway beat a device in straight up function without needing to buy extra accessories this hard is quite laughable.With all that being said I do wish that instead of a 2.5mm balanced output we instead got a 4.4mm balanced output port. Something the Btr7 does have over the Qudelix-k5.I know in this review I talked about the btr7 alot, Probably more than the k5 itself but I seriously need to get across to you the reader that this device far outperforms the in my own personal experience frustrating to use, far more expensive and in my own opinion wasteful device. You spend about double the price for just a bit more power and a funny little screen which is nice but it is not needed and it CERTAINLY is not 100$ more worth it in my personal opinion. In all honesty as far as I can tell you just simply can't beat this tiny little monster for its price to performance. The amazing software, amazing audio quality, amazing bluetooth connectivity. The sheer thoughtfulness of the designers of this product made a product for you with the intention that you are going to use this daily and you will not be disappointed in what you paid for.

After upgrading from a LG V30 to a phone that doesn't have a headphone jack (Thanks Samsung -.-) I needed a DAC that could drive the planar magnetic HifiMan HE-560 v4 that I use daily, and this seemed to fit the bill, having the output power needed to drive these hungry headphones (it also works well with my higher-impedance Sennheiser HD 650). I've seen the FiiO BTR5 as well, and my first impression on getting this was just how much lighter and smaller the 5K is; feels like half the size. You do miss out on the premium-feeling glass and nice display, but the 5K still seems well built.It also sounds great on both 3.5mm and 2.5mm TRRS; one of the best features I think is that you have two digital volume controls; basically, you can set a volume 'cap' on the 5K itself and then use your Android volume controls to step within that zone. The on-device steps are 0.5dB each which makes finding that 'perfect' volume easy.One caveat is that the on-device controls are a bit fiddly to get used to; when I first got it in the box I struggled to figure out how to even turn it on and off, since all you get are two rockers, a red LED on one side, and a blue LED on the other. If you open the app and go to the 'MISC' section, you can see what actions the buttons are bound to and do a bit of customization as well. I don't touch them often except to pause/skip, adjust volume, or power on/off, so it works well enough for that.Speaking of the app, this is one that I actually consider beneficial - it lets you change the volume and set up EQ, but it also lets you configure a lot of things inside of the firmware, like what codecs to advertise, what bitrate to use for USB, and what input to prefer (you can have two Bluetooth devices connected at once, and it'll play audio from either one at a time, not mixed). All of the defaults are fine, but clearly a lot of technical thought has gone into exposing these settings to the user, which I appreciate. Showing the LDAC bitrate was particularly useful when I was trying to figure out why sometimes my tablet sounded worse (looks like it was dropping to 330Kbps).Overall, it's a puny portable, USB+Bluetooth DAC that sounds great and is filled to the brim with features for those who want to tinker with the way it sounds.P.S. For those looking for the 2.5mm pinout, it's (from the base to the tip) L-, L+, R+, R-. Couldn't find it anywhere, not even in the docs...