Qudelix-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.

This review is geared towards people like me. I am a music lover. A novice audiophile (maybe?) with a headphone fetish (absolutely!). My wired headphone collection includes a few over ear open back sets, a few Chi-Fi IEMs, and every on-ear with a 60-ohm driver that Koss sells :)I've been toying with the idea of purchasing a DAC/AMP for a while, but only recently discovered the Qudelix-5K. Based on the price point and the shear amount of recommendations that this unit receives on the forums, I knew I had to look into it. Now, if you are reading this review, you are most likely in the same spot that I was in at this point in my research. You have read about the powerful EQ capabilities and the companion app with more options than you can shake a stick at. And, if you are anything like me, you are at least a little hesitant, concerned that the "true power" of this device will be over your head. DON'T BE! Let me break it down for you:1. The app truly is wonderful. Sure, it doesn't have the fanciest UI, but it is easy to navigate. Yes, there are a lot of options that may seem overwhelming at first glance, but everything is thoughtfully documented within the app. Speaking of thoughtful documentation...2. The user manual is great. It is accessible right in the app under the DEVICE tab. I suggest spending a few minutes with the user manual right away, before you start listening. The first section provides some valuable information on key setting for the Quedelix-5K which can impact your first impressions of the device. As an Android user, the section up front on how to change the bluetooth codec on your phone to Sony LDAC was invaluable and greatly increased the sound quality.3. Before purchasing this unit, I was concerned that the EQ functionality would be overwhelming but is absolutely fantastic! Now look: I have a basic understanding of frequencies and equalization and can follow along (to some extent) with the technical jargon, but if I try to EQ a pair of headphones myself from scratch, I will probably do more harm than good. That is where the Auto EQ Presets come in!A) I don't care what they are, there is probably and Auto EQ Preset for your headphones. At least, there is an Auto EQ Preset for every pair of headphones that I own. Amazon Chi-Fi IEMs, check. Cheap Koss on-ear headphones, yup. All of 'em. No kidding.B) Every Auto EQ Present that I've tried made that particular set of headphones sound better. Now I understand that this is subjective. Maybe you don't like the reference curve that was used. Maybe you just want to do it yourself. Can you EQ yourself to make it sound better TO YOU? Absolutely, and Qudelix has certainly given you the tools to do it. But that's not me. I very much appreciate the Auto EQ Presets.I have made some minor tweaks here and there to suit my preferences. For instance, the Auto EQ Preset for my QKZ x HBB IEMs has a low shelf applied to reduce the bass. I understand that this is probably technically correct, but I wanted my bass back! The extra bass fun factor is the main reason I bought these IEMs, and why I listen to them over more expensive IEMs for some music. No problem, save the Auto EQ Preset to a Custom user preset and remove the low shelf! Which brings me to:C) You can use the Custom presents to save the Auto EQ Preset for easy access (whether you tweak it or not). First, look up your headphones on the AUTO EQ PRESET tab. Now go to the EQUALIZER tab and click on the graph to bring up the list of Custon #X presets. Long pressing one of these brings up the "Save Custom Preset" screen, which allows you to name the preset and record the Impedance and Sensitivity. Do this for all of your headphones, and you can easily recall the EQ curve with any modifications that you choose to make. In the future, plug in your headphones of choice, turn on the Qudelix-5K, click on your saved EQ curve for those headphones, and you are off. Easy!4. Most important, it makes everything sound better. I don't subscribe to Tidal. I listen to YouTube music. I would like to try out high-res or lossless at some point, but for now I am happy with what the Qudelix-5K does to my mainstream sources.So, there you have it. The Qudelix-5K sounds phenomenal and is an absolute no-brainer for its price point. It has all the options that the techy audiophile could wish for, and an "easy mode" for the rest of us that just want a great sound with minimal fuss. If you want your music to sound better, buy it. It's that simple.

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.