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

This is my first DAC/amp. I bought it mostly based on the hype and positive reviews, and because I wanted something portable with a lot of flexibility. Overall this is an excellent DAC/amp for the price with a really strong feature set. Bluetooth supports most of the important codecs, and the balanced 2.5mm output is a big plus for something this small. In 2025 I do kind of wish it used 4.4mm instead, but it’s not a deal breaker. Sound quality is clean and has more than enough power for the headphones and IEMs I’ve tried. It also has battery passthrough and lets you set safe charging limits, which is a nice touch if you care about battery longevity. The app is one of the best parts. There are a ton of options, it’s actively updated, and it feels like the developers actually care about supporting the product. Build quality seems fine for daily use, but it’s basically a chunk of plastic with a clip, nothing fancy. The buttons take some getting used to, and there’s a lot I still haven’t messed with yet. This probably isn’t the device for someone who just wants super simple plug-and-play. But if you want flexibility and control in a small portable DAC/amp, it’s hard to beat for the price.

The Qudelix 5K truly is an awesome product. Don't know if it's exactly worth the price but it certainly is excellent. I've been using it paired with Truthear Hexa IEMs and with an iPhone/Mac/Windows PC over Bluetooth and USB (for each device). It's a great product effectively delivering a GREAT sound quality. I can't hear any difference with my IEMs used directly with the cable. It's awesome for this. With such IEMs, power will never be a problem as you'll completely annihilate your ears before you reach half the full volume of this thing. The volume automatically syncs with your device's so that it always delivers the best audio quality no matter the volume set on the source device (you don't have to worry about absolute volume on Bluetooth). The app is incredibly full of options. There's settings for EVERYTHING. I never had any lag when changing the settings, they're well saved, it's responding lightning fast, you can set an EQ with up to 20 bands... I can't say much about durability yet, but it's very small. I could fit two of these products inside a single hand. The clip is really good so I can attach it to my jeans, vest, or anything really. It's light enough that if it ever falls, the cable of the IEMs will retain it from falling. Oh and also, you can connect (simultaneously) up to 2 devices over Bluetooth as well as an additional device over USB (all 3 at the same time). It switches very intelligently and quickly over these 3 devices. The integrated microphone isn't very good, but I'm pretty sure no one will buy this product for that. If needed, you can plug in an external mic to use with it. It works flawlessly and is also available to set up within the app. If you're wondering whether you should buy this product, just buy it. It's EXCELLENT.

This little DAC is incredible! The Bluetooth is reliable and has great range, along with the ability to control almost any settings you can think of. The battery lasts as long as I could reasonably want and its wonderful to be able to simply unplug it from my computer to switch from USB mode to BT mode. The custom EQ is obviously a huge selling point of the device, and it doesn't disappoint. While audiophiles will argue to the ends of the earth about how various BT modes might sound, nobody could reasonably pretend that any of that makes half as much of an impact as a good eq! The audio quality is incredible, and the ease of use is even better. Near instant device switching, a fantastic app, easy to use EQ, and a convenient form facto really make this the one adapter to ruel them all.

Why did I buy the Qudelix-5K? I have Sennheiser HD560s high impedance (120ohm) open-back headphones that sound great but don't have bluetooth. I got an Earstudio ES100 MK2 bluetooth unit with an included amp and its own digital-audio converter [DAC] (which I love), but it was not able to power the HD560s to full potential. The ES100 MK2 was strong enough in most situations but not strong enough in too many. Here is how the Qudelix-5K solved this and provides exceptional features in other areas as well. Power: The Qudelix provides more than adequate power for my high impedance (120 ohm) Senn HD560s. It provides two power settings, and the lower setting is adequate to power the HS560s. (Both settings allow use of the superior balanced connection that uses both of the Qudelix internal amplifiers.) I am waiting to see if the higher power setting will be enough to also power my low-sensitivity (93.5 dB) Hifiman Deva [waiting for a proper balanced cable], but I think that it should also be adequate for this headphone as well. Problem solved! And this will also provide enough power for most high impedance/low sensitivity headphones. This is a huge benefit for those wanting to add bluetooth to power-hungry audiophile headphones (or replace the headphone's own bluetooth with the Qudelix to be able to use the additional features of the Qudelix). Equalization (EQ): The Qudelix provides both a standard [GEQ] and a parametric [PEQ] equalizer. While a standard equalizer allows adjusting the sound profile at predefined frequencies, a parametric equalizer allows specifying the frequency and the type of adjustment to be made. For example, the GEQ will allow adjustment of a specific bass frequency but will not be able to extend beyond the predefined lowest frequency. The PEQ will allow specifying a specific bass frequency and allow using a filter that extends the impact to all frequencies below the one specified. I was concerned that the PEQ might be too complicated to use, but the Qudelix website provides a link to research-based reference EQ settings for hundreds of ear/headphones. I was able to simply find the settings for my Senn HD560s and key them into the Qudelix (took about 3 minutes). This resulted in the elimination of some [difficult to listen to] shrillness in the treble, extended the bass (which is a problem inherent in most open-back headphones), and improved the imaging (the placement of instruments within the soundstage). What a bonus! I should have planned to get the Qudelix simply to get the PEQ on its own merits! [Note: Even though my Hifiman Deva comes with its own powerful bluetooth/DAC/amp (which provides outstanding sound!), I expect that the PEQ of the Qudelix may well make the Deva sound even better as well.] [I also tried the Qudelix with my Sony WH1000MX3, and the sound was also improved substantially! Unfortunately, this sacrifices the automatic noise reduction (ANC) feature of the Sony's, so I will probably just relegate their use to noisy environments and be less satisfied with their sound.] Battery: The battery of the Qudelix lasts longer than the ES 100 MK2 at the same settings. However, the Qudelix provides many additional features and power settings that can use more power, so it is important to understand the relationship between settings and power use. To address this, Qudelix has gone beyond simply providing a battery percentage by also providing a graph of power/battery use. Brilliant! I wondered why I just wouldn't set the Qudelix to the higher power setting for my Senn HD560s, but the battery graph allowed me to see the impact of the higher power setting and the advantage of the lower setting. This is something that the competing ES100 MK2 and Fiio BTK5 do not provide! Qudelix Updates: Qudelix provides over-the-air (OTA) updates to the 5K. This means that updates can be applied directly from the application rather than having to use the complicated process of connecting to a PC and using commands to download, process, and apply the update (as both the ES100 MK2 and Fiio BTK5 require). This allowed a simple immediate update before first using the Qudelix and has allowed Qudelix to provide continuing updates and fixes. This is a huge difference! Think about it - without an easy to use update process, competing products will be hesitant to issue updates or users will simply not go to the trouble to update. This has allowed Qudelix to continue to add useful features while competitors have fallen silent! Bluetooth Range: While maybe not a critical factor, the Qudelix has an extended bluetooth range. While the ES100 would start to have dropouts at the furthest points in my house, the Qudelix (because of its high-tech antenna?) has no drop-outs at the same distance. Summary: While I bought the Qudelix to get higher power from an add-on bluetooth unit, it is the additional features that make it so much better than the competition. For about the same price as the competition, the Qudelix provides better performance and features plus the ability to continue to get continued updates and additional features that make the Qudelix stand out in comparison.

This was the first DAC/AMP I have ever purchased and it set the bar pretty high. The device itself is very minimalist with just 2 rockers on either side of it. This takes some getting use to in order to remember the various combinations of holds, presses, and long-presses to perform different actions. There is software for the device. Its main function is configuration, which it does not lack. The issue is that the software is really technically. The PC version, which is a Chrome web application is worse because it forgoes a lot of the minimal GUI elements of the mobile app. There is text in the app that should explain things. Bu,t it gets almost there then either sends you to Qudelix's website or just ends. So while you can get by with just plug and play beyond that the documentation is hit or miss. The sound quality is pretty good. It is hindered by the fact that the 5k only supports up to 24-bit/96kHz sample rate. So Tidal song with the Max tag will warn you about resampling. With its bluetooth implementation including LDAC and aptX (including HD and Adaptive) codices you can even enjoy Lossless audio wirelessly. I haven't noticed any distortion. Lastly I would wholeheartedly recommend this device if the Fiio Retro Nano did not exists for about $40 less with most of the same features.

Great little device and totally worth it. If you’re using good wired headphones, this is a perfect way to keep using them with an iPhone. Works flawlessly, the interface is easy to understand, and Bluetooth works really well. I mainly use it with my 64 Audio U12t and it drives them without any issues. Sound quality is excellent.

I had a bad cable on my IEMs which ended up damaging one of the amplifier chips in my EarStudio ES100 MkII (some crackling in the left channel on both 2.5mm balanced and 3.5mm unbalanced). When looking for a suitable replacement, I wanted something that was at least the same level of functionality and configurability as the ES100 but with USB-C. The decision came down to the Fiio BRT5 and the Qudelix-5K as both had USB-C and a 2.5mm balanced output (BRT15 was out since it did not have 2.5mm balanced). After seeing how configurable the 5K was through the app, it was a no brainer for me. SOUND QUALITY: In terms of sound quality, I cannot tell a difference between the ES100 MkII and the 5K. Granted, I have only used one set of IEMs for daily listening (Etymotic ER2XR) and cannot do A-B testing since my ES100 is damaged, so far from a scientific comparison. There is no hissing at all that I can tell when things are quiet or music paused. The volume goes higher than I would ever want to go. I have absolutely no complaints about the sound quality. It is honestly incredible how much value you get from something so small and portable! Definitely in the top of this price bracket! ANDROID APP: In terms of the app, it is a function over form sort of affair. It isn't the most intuitive layout with each section or page having multiple tabs. Sometimes it takes a bit of hunting around to find the setting you want to mess with. Also, there is a lot of plain text with little styling to distinguish between a simple status or reading and a configurable option. It is a simple black background with white, grey, and red text. The functionality is all there and I have no complaints about what it is capable of, just that it could use the touch of someone who specializes in user interfaces to take it to the next level. 5/5 on functionality, 3/5 on ease of use. BATTERY: As for battery life, this is really where I wish things could be better. Compared to my 2.5 year old ES100 MkII, I get significantly less battery life out of the 2.5mm balanced output on the 5K. I'm using the 5K in much the same way I did with the ES100: LDAC from my phone (44.1KHz sample rate, 24-bit, adaptive bitrate that often sits at 909/990), 2.5mm balanced output, ER2XR IEMs, similar listening volumes, no DSP/EQ enabled, no oversampling, battery charging limited to ~80%. With the ES100 MkII I could get 10-12 hours of listening on the balanced output. With the 5K, I'm only getting around 7-8 hours. I am charging every day or two which is too frequent for me (battery capacity will degrade to 80% of nominal in only a few years at this rate). That pushed me to create an adapter to turn my 2.5mm balanced cable into a 3.5mm unbalanced cable to see if I could notice a difference in audio quality and battery life. Using 3.5mm unbalanced with normal gain (1V RMS) and performance mode at the exact same listening volumes on the same IEMs, I get 10-11 hours of listening from an 80% charge (3-4 hours more than before). The audio quality is slightly worse as far as I can discern with everything being slightly more muddy and less refined, but I can only tell when looking for a difference, not during casual listening. Considering the gain in battery life is significant and I cannot make the 2.5mm balanced output battery life any better, I think I will continue to use my custom adapter cable that way I can choose between balanced and unbalanced at any time. I may also resort to simply plugging the 5K into a charger while sitting at my desk and disable charging so the battery doesn't experience any unnecessary wear. That is one thing I do really like about the 5K, the behavior when plugged into USB is very configurable and does not disconnect or interrupt the bluetooth connection unlike the ES100. I can plug into or disconnect from USB, change most settings, enable or disable charging, etc. all at will without interrupting my listening session. OVERALL: For me, the Qudelix-5k is a no-brainer for IEMs! The price is spot on for the features, sound quality, portability, and and flexibility you get out of this device. The battery life is less than I would like but I would consider myself a heavy user with 4-8 hours of listening most days of the week. Either way, this is certainly a device I can recommend!

I was looking for a portable DAC/amp for my IEMs, and I found the Qudelix 5k in stock at Amazon. It is a killer Bluetooth DAC/amp, and I cannot recommend it enough. Build Quality and design: The build itself is decent, but the buttons feel cheap. Also, the button placement took me a while to memorize. On one side is the volume up/down button, and on the other side is the power, play/pause, and track skip/rewind button. The latter button has a bump so you can feel it by hand, but it took me a long while to feel the buttons and use the 5k without looking. Power and sound quality: The 5k is rated at 80mw single ended, and 240mw balanced (at 32 ohms.) Yeah, it doesn’t seem like a ton of power, but the 5k can easily power all my headphones and IEMs, ranging from Focal Elear, Moondrop Blessing 2, Moondrop S8, and even the Hifiman Sundara (though out of the 2.5mm balanced output.) As for sound quality, I can’t tell the difference between the Qudelix 5k and my JDS Labs Atom+ stack. App: This is the main reason to buy the Qudelix 5k. It has an app for Android and iOS, as well as a Chrome extension for PC and Mac users. The app has tons of functionality. The eq section of the app is its main selling point. You get a 10-band parametric eq along with all of the AutoEq presets by Jaakkopasanen. It includes all presets from Oratory1990, Crinacle, and others. This is perfect for iOS users who want the AutoEq function. For example, I bought the OG Moondrop Blessing 2, and I wanted to try the Dusk eq profile. I can easily do this via the Qudelix app on my iPhone. Another feature of the app I really like, and one I don’t see people mentioning, is the battery section. It shows you at what rate the battery life is decreasing/increasing, and it also lets you set the battery limit to 80% to prolong battery health. Also, when the Qudelix 5k is plugged in to PC/Mac, it bypasses the battery when in use. Conclusion: I highly recommend buying the Qudelix 5k for portable use. My main gripe is the odd button placement, and that’s it. The app functionality is amazing, the battery life is very good, and it has enough power for all my IEMs.