Caseten's Qudelix-5K Quick Start Guide

Qudelix-5K Quick Start Guide

by caseten

The Qudelix-5K is not user-friendly and will be frustrating to use initially. The amount of options in it’s App can be overwhelming at first. Be patient. It has a ton of features, but the AutoEQ Preset feature is the ‘killer app’ of this device.

You probably purchased the Qudelix-5K for the AutoEQ feature, or the Equalizer feature or the form factor or price. If you don’t plan to use the Auto EQ or EQ feature, save yourself the headache and get a simple, plug-and-play dongle DAC.

CRITICAL NOTE 1: Even if you plan to use the Qudelix-5K in USB DAC mode, you will need to pair it to your smartphone via Bluetooth and properly configure the device before first use.

CRITICAL NOTE 2: Qudelix states, “Any standard 5V USB charger, USB-C PD charger or PC USB port can charge 5K DA/AMP. 5K DAC/AMP does NOT support fast charge. With any charger source, the maximum charging current is limited up to 200mA by 5K DAC/AMP.” If you plug your Qudelix-5K into a fast charger it may become damaged. You’ve been warned.

Step 1: Download the User Guide: If you Google: “qudelix-5k_user_manual-pdf”, you will find a link to the user guide here:

This user guide is 28 pages, and out of date. I’ll show you how to get the updated user guide from the Qudelix app later. Make sure to read pages 3 and 4 of the user manual linked above. The 5K looks like it has two buttons, but there are actually 4 buttons since each ‘button’ (left side and right side) are multi-function (i.e. toggle) and have a “upper” button and “lower” button. The button with the “bump” is the blue button (power button) and the smooth button is the red button (volume buttons).

Step 2: Download the App: Download the Android app. Go to the Play Store and search for Qudelix and download the Qudelix app.

Step 3: Open the App: Open the Qudelix App. It should start on the DEVICE screen. We will use this screen to monitor the CONNECTION status.

Step 4: Locate the Power Button (and memorize the buttons functions):

Review the Qudelix webpage on the power buttons:

To power on the device press/hold the lower blue button for 3 seconds, until the red and blue lights start flashing.

Step 5: Pair the Device: The blue and red lights flashing indicate that you are in ‘pairing mode’. Pair the Qudelix-5K with your smartphone. Unfortunately, you’ll need to use your smartphone to properly configure the device before first use. This product is not plug-and-play.

CRITICAL NOTE 1 (Yes, again): Even if you plan to use the Qudelix-5K in USB DAC mode, you will need to pair it to your smartphone via Bluetooth and properly configure the device before first use.

Step 6: Verify Device Connection: Go back to the Qudelix App on your smartphone. You should be on the DEVICE screen. If not, press the ‘gear’ ⛭ in the lower left hand corner of the screen that says DEVICE.

Towards the top of the tab there should be a field that says CONNECTION. This should now say, “Qudelix-5K”, and display the current firmware (F/W) VERSION and # of WARRANTY days left. If so, you have correctly connected to the device. If not, touch the CONNECTION text and see if it will now connect to the Qudelix-5K.

CRITICAL NOTE 3: If the device is not connected, review the steps above again.

Step 7: Set device to Power ON at USB DAC connection: Go back to the Qudelix App on your smartphone. You should be on the DEVICE screen. If not, press the ‘gear’ ⛭ in the lower left hand corner that says DEVICE. Select the POWER tab. In the POWER tab select ON at USB DAC.

Step 8: Review the Input State: Select the Bluetooth symbol at the bottom of the Qudelix App screen that says INPUT. This will take you to the INPUT screen. If you are connected, the state may have N/A in all the fields. This is because not music is playing. It is displaying the ACTIVE STATE. You can toggle between the DEVICE screen and INPUT screen to see the current connected mode.

Step 9: Setting the Codec: If you plan to use this as a Bluetooth device, check the codes and make sure the codec you want to use is enabled and disable any codecs you don’t plan to use. I use this device as a USB DAC, so I don’t care.

Step 10: Setting USB: Select the USB tab at the top of the INPUT screen (you should already be on this screen). Select the USB DAC FS you want. I suggest choosing the 44.1/48/88.2/96 KHz setting.

CRITICAL NOTE 4: Setting the USB DAC FS is CRITICAL. If you plan to use this as a USB DAC (which I do, for reasons of sound quality), you will probably want to select the 44.1/48/88.2/96 KHz setting. If not, you will be unable to get ‘bit perfect’ output from USB Audio Player Pro.

USB Audio Player Pro

Step 12: Set the connection Priority: Select the PRIORITY tab at the top of the INPUT screen (you should already be on this screen). Select the USB DAC FS you want. If you plan to use this as a USB DAC (which I do, for reasons of sound quality), you will probably want to select the USB DAC setting.

Step 13: Adjust the VOLUME (hardware output voltage): Select the VOLUME page by pressing the VOLUME icon at the bottom of the Qudelix App. Set the desired hardware output VOLUME. I suggest setting it to MAX, RMS 1.95 V. On this screen you can also see how the device is connected. Between the volume bars you will see a Bluetooth symbol or a USB symbol, depending on how the device is connected.

Step 14: Set the DAC/AMP Mode: Select the symbol at the bottom of the screen that says DAC/AMP. I set the PROFILE to PERFORMANCE the OUTPUT POWER to HIGH (because I use full sized headphones, set to NORMAL for IEMS), and OUTPUT MODE SELECTION to AUTO.

Step 15: [OPTIONAL] Connect to the PC: If you want to connect to the PC, go ahead and do so now.

If you are at your PC, go ahead and connect the Qudelix-5K and see if you can get audio to playback via Tidal, Qobuz, AmazonHD or similar.

You’ll notice that when you connect to the PC the RED LED comes on to indicate that the Qudelix-5K is charging. The RED LED will turn off when the device has reached 100% battery.

You can also take the opportunity to download the Qudelix Chrome browser extension :

The Chrome extension provides the same user interface as the Android App and may prompt you to download and install a firmware update.

If you scroll down to the bottom of the DEVICE page in the Qudelix Chrome browser extension you will find a link to the updated USER MANUAL under HELP. Go ahead and download that now. The latest User Guide is labeled July 2021 and has 41 pages.

Step 16: Connect to your smartphone via USB: This one is easy. Just connect the Qudelix-5K to your smartphone via the USB-C connector


Step 17: Equalizer and AutoEQ: You probably bought the Qudelix-5K for the AutoEQ feature or the Parametric EQ. To use the EQ select the DSP icon on the lower right hand side corner of the Qudelix App.

Here you will find the EQUALIZER. You can enter values in manually if you already have settings from Equalizer APO. You can enter the filter type, frequency, gain and Q values manually. Or you can select the AUTO EQ PRESET tab and search for your headphones and automatically apply an existing EQ Preset.

Select the AUTO EQ PRESET tab in the upper right hand corner of the Qudelix App.

PRO TIP 1: Grab and drag the red slider on the right to quickly find the preset you want. Get close then scroll normally.

Select any one of the Auto EQ presets and it will be automatically applied. Then select the EQUALIZER tab in the upper left hand corner of the Quedlix App to see the EQ curve.

This is unintuitive, but when you touch the graph, the bottom of the screen will change from the manual entry screen to the preset screen. If you hold down any of the Custom preset slots a text dialog box will pop up to allow you to rename that slot and it will apply whatever EQ settings were displayed on the EQ graph. You can toggle between the manual setting screen and the custom EQ presets by tapping the EQ graph.

That’s it. You should be good to go. Now go read the 41 page user guide.

Quirks and Complaints:

It’s obvious that Qudelix designed the Qudelix-5K as a ‘Bluetooth first’ device. The app will ask you “Qudelix is asking to turn on Bluetooth,” if you turn Bluetooth off. This means you have to check the app to ensure you are in USB Audio mode when connected via USB. Easy enough, but annoying. You should just be able to run this as a USB DAC without having to configure Bluetooth whatsoever.

An open letter to Qudelix:

Dear, Qudelix,

You really need to have better default settings for this device and allow USB DAC use with ZERO configuration. The Qudelix-5K should be plug-and-play. It is not! You need to include a Quick Start Guide in your packaging. I’d be happy to write you one for free, provided you make the following improvements to your Qudelix App and change the default settings:

  1. Allow operation without needed to pair with Bluetooth. Input priority should be USB DAC by default and connecting the Qudelix-5K by USB should exit Bluetooth pairing mode.

  2. Power should be On at USB DAC by default.

  3. USB DAC FS should be 44.1/48/88.2/96 KHz by default. Not just 96 KHz. This is so USB Audio Player Pro can run in bit perfect mode out of the box.

  4. Volume should be set to Performance 2 VRMS Unbalanced (RMS 1.995 [V]) by default.

  5. Equalizer needs a button to toggle between Custom Presets and Manual EQ entry. Tapping the graph to switch is not intuitive. Also, you should put draggable points on the EQ graph that match the entered frequency so you can drag the gain values (up and down), so you can adjust the sound by touch.

  6. You need a ‘spyglass’ on the AutoEQ page so we can search for the EQ Presets in a dialog box with auto complete. There are just too many to scroll through.

  7. Create a Basic (simplified) user interface. While I appreciate all of the options, most of them should be hidden in Advanced Settings. The big selling point for your device is the AutoEQ feature. Make the device plug-and-play and put the AutoEQ feature front and center.

  8. Make it so the Android volume can control the Qudelix-5K volume. Using volume up/down on my smartphone or on the Qudelix-5K should have the same result. You’ve over complicated the volume on this device. I like the volume features, but they should be in advanced settings.

  9. Have a native English speaker rewrite your User Guide. I’d be happy to do it for free if you address the issues above.

Thank you.


Being a daily Qudelix 5k user and absolute fanboy of it, I saw this and went into it thinking “I’m going to see if I agree with everything he says, and I’ll ask/say what I would like to add or discuss.” But after reading it, bravo! This guide is very in-depth and well thought out, and your feedback for Qudelix regarding some changes for the app are pretty much spot-on. So, the only things I feel like I can add are my opinions and thoughts on the Qudelix 5k, eq in general, and some other stuff. Seriously great job on creating this guide, and I hope Qudelix gets back with you on some of that stuff.

For me personally, the app can of course use some improvements, but for the time being, I am absolutely more than willing to live with the quirks and not-perfectly-user-friendly things about the app because…Qudelix simply doesn’t have any real competition in their niche of the audio market. As I know of, this is the only product that has a 10-band fully parametric eq along with its form factor, power, performance, etc… At least you can fix most of nit picks you mentioned in settings, and you don’t have to change them again (such as USB having priority over bluetooth). I’m young and technically inclined, so navigating the app has actually been fairly easy for me. It just took about a week to get used to.

The only area I diverge from your guide is that I personally keep the power mode in normal and keep the maximum hardware volume set at -3dB because I only ever use iems and efficient dynamic-driver headphones with the qudelix.

For anyone reading this that might be new to this hobby and/or are considering buying the Qudelix 5k, know that it is a dongle dac/amp that is not meant to drive medium-to-hard to drive headphones, especially power-hungry planars, nor is it meant to be used as only a dac going into a more powerful amp. It is an excellent, imo best in its class, device when used for its intended purposes, which is being a tiny portable dac/amp for iems and efficient headphones. If you’re looking for something in that use case that has a fully parametric eq, than this is currently the absolute best thing out there imo. For iPhone users like me, the Qudelix 5k is actually the only option for system-wide parametric eq, besides much more expensive desktop stuff like the RME ADI-2, which only has 5 bands. I’ve used the Qudelix daily for the past couple of months, and it has still not dipped below 50% charge: the battery is AMAZING. I recommend switching the maximum charge to 80% in the app because lithium batteries last the longest when between 20-80% charge.

Amir from audiosciencereview measured the power that the Qudelix 5k can put out:
(the 2.5mm output provides 4x the power!)

For anyone new to eq or just wanting to learn more, check out Resolve’s video guide for eq

, and I actually recommend checking out the rest of the Headphone Show’s educational playlist as well as Crinacle’s video on eq.
Step one: set the pre-gain (pre-amp, whatever it may be called) as minus the maximum gain of your eq preset. For example, if the highest peak of your eq preset is at 4.8dB, set the pre-gain to -4.9dB.
In the videos, Resolve and Crin make clear and I will say it again, the Auto-eq presets are not the end-all be-all heaven-sent silver bullet. They are simply someone else’s preference preset and should be treated as such. You may like them and tweak them to perfectly match your tastes. In my experience, the Koss KPH30i preset is amazing, and after dialing tweaks to my tastes, that $40 headphone is absolutely spectacular (tonality-wise). However, they may not sound good to you, and you may have to type in someone else’s preset, such as Resolve’s, or you may just have to do it by ear. So far, all of the presets for iems have been a miss for me. Even if you like a preset, still try to eq to your own ears and preferences because everyones’ are different.

1 Like

Nice start guide!

I am not sure if I fully agree with your proposal though. Qudelix-5K is indeed a Bluetooth-first device. I think it would be nice if you could plug it into usb and it would just work out of the box. But I am not sure if USB should take priority over Bluetooth by default – that way you can use it in Bluetooth mode and charge at the same time.

Thanks a bunch!! This is going to be great help when it arrives. I can finally stop using Peace EQ and not being able to let Tidal communicate directly exclusively with my DAC (it sounds worse to my ears, but no PEQ is even worse!)