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Qudelix-5K Bluetooth DAC & Headphone Amp

ishouldbeking

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Just got the Qudelix. It's so small! What a cool little design, and the app is so feature-rich I haven't even begun to scratch the surface. Initial impressions: this thing feels thoughtfully designed and subjectively sounds very good thus far and I'm looking forward to playing with the PEQ.

Question: If I'm using this in USB DAC mode between my laptop and JDS Atom, listening to stuff like Spotify (set to highest streaming quality), youtube (normal/potato quality), and typical computer sounds (Zoom and Skype calls mainly), what sample rate should I choose? Options are 96, 88.2, 48, 44.1 and some kind of multiple option I'll admit I don't understand (listed as "44.1/48/88.2/96"). I've tried them all and didn't notice an obvious difference, but if I try to select the multiple/variable option it tells me the device needs to restart, so I haven't actually tried that one yet. Any reason not to just leave it set to the default of 96?
 

Atanasi

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Just got the Qudelix. It's so small! What a cool little design, and the app is so feature-rich I Options are 96, 88.2, 48, 44.1 and some kind of multiple option I'll admit I don't understand (listed as "44.1/48/88.2/96"). I've tried them all and didn't notice an obvious difference, but if I try to select the multiple/variable option it tells me the device needs to restart, so I haven't actually tried that one yet. Any reason not to just leave it set to the default of 96?
If used as a USB DAC with the default 96, 96kHz sample rate is the only available option. I suppose 44.1/48/88.2/96 means the DAC lets the host computer choose. Normally either 44.1 or 48 are good choices, as most of the media is either of these.
 

ishouldbeking

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If used as a USB DAC with the default 96, 96kHz sample rate is the only available option. I suppose 44.1/48/88.2/96 means the DAC lets the host computer choose. Normally either 44.1 or 48 are good choices, as most of the media is either of these.

I should probably read up on this a bit more, eh? It does give the option to choose between all of those, and they all seem to work fine, so I'm assuming Windows 10 is just resampling as it goes. If my primary focus is maximizing fidelity for spotify and itunes, is the general recommendation just to use 44.1? I'm not as concerned if my zoom calls wind up resampled :)

EDIT: did some more searching and see that this was already discussed earlier in the thread (the manufacturer even chimed in), so please feel free to ignore. (I will set it at 44.1 and leave it be.)
 

m_g_s_g

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Hi. I just bought and received a short USB-C to lightning OTG connector (14$ + shipping @ aliexpress) and plugged it from my iPad to my Qudelix 5K. Now I can use them without bluetooth.

The sound is great, but I didn't find an easy way to switch quickly enough between USB and bluetooth/AAC to properly do an A/B test to compare...
 

Palex

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Long I chose that to buy Qudelix 5K, BTR 5 or ES 100 …. and after long thoughts, I have got from a table of iPod nano 6, I "have thrown" Hi-Res 24/48. "It isn't necessary to invent the bicycle"))))
The opinion - Amirm is interestingly interesting
 

ishouldbeking

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Question for my Qudelix people regarding PEQ and low pass filters: I'm trying to translate one of Amir's EQ settings into the 5K's PEQ but not sure how to do it when setting up a Low Pass Filter. I can set the frequency fine, but I'm not sure how I should be setting the gain or Q columns to account for a 0dB/octave curve when I'm limited to the particular inputs in the Qudelix app.

Amir's filter is set like this: LPF, 10k, 0dB/octave
My filter is set like this: LPF, 10k, gain: 0.0, Q: 1.414 (the default Q)

As currently set with Q at 1.414, it actually looks like it's boosting treble a few db before a steep rolloff. I tried messing around with gain and Q settings to see if I could approximate a graph that looked like his, but I'm pretty much in the dark. Adjusting gain doesn't seem to do anything. Adjusting the Q radically shifts the behavior of the rolloff. At 1.414 it boosts treble, then rolls off fast. At 1.0, it has a minor treble boost, followed by a slightly slower rolloff. At 0.9, it actually looks pretty close to Amir's graph, just a faint treble bump. At 0.8, it looks the closest I can find to Amir's, and any lower than that starts to roll off much sooner. I tried it set at 0.1, and the rolloff started at like 250hz.

Can anyone explain what I'm actually adjusting when I adjust the Q this way for a low pass filter? And how should be setting it to achieve 0dB/octave? For now I'm eyeballing it and leaving the Q at .8, but I'll admit I have no idea what I'm doing.
 

abdo123

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Question for my Qudelix people regarding PEQ and low pass filters: I'm trying to translate one of Amir's EQ settings into the 5K's PEQ but not sure how to do it when setting up a Low Pass Filter. I can set the frequency fine, but I'm not sure how I should be setting the gain or Q columns to account for a 0dB/octave curve when I'm limited to the particular inputs in the Qudelix app.

Amir's filter is set like this: LPF, 10k, 0dB/octave
My filter is set like this: LPF, 10k, gain: 0.0, Q: 1.414 (the default Q)

As currently set with Q at 1.414, it actually looks like it's boosting treble a few db before a steep rolloff. I tried messing around with gain and Q settings to see if I could approximate a graph that looked like his, but I'm pretty much in the dark. Adjusting gain doesn't seem to do anything. Adjusting the Q radically shifts the behavior of the rolloff. At 1.414 it boosts treble, then rolls off fast. At 1.0, it has a minor treble boost, followed by a slightly slower rolloff. At 0.9, it actually looks pretty close to Amir's graph, just a faint treble bump. At 0.8, it looks the closest I can find to Amir's, and any lower than that starts to roll off much sooner. I tried it set at 0.1, and the rolloff started at like 250hz.

Can anyone explain what I'm actually adjusting when I adjust the Q this way for a low pass filter? And how should be setting it to achieve 0dB/octave? For now I'm eyeballing it and leaving the Q at .8, but I'll admit I have no idea what I'm doing.

The second post in every Amir review is a member with Anime profile pic that gives the settings for APO equalizer.

There you will find the settings that will better match Quadelix.
 

pwjazz

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Question for my Qudelix people regarding PEQ and low pass filters: I'm trying to translate one of Amir's EQ settings into the 5K's PEQ but not sure how to do it when setting up a Low Pass Filter. I can set the frequency fine, but I'm not sure how I should be setting the gain or Q columns to account for a 0dB/octave curve when I'm limited to the particular inputs in the Qudelix app.

Amir's filter is set like this: LPF, 10k, 0dB/octave
My filter is set like this: LPF, 10k, gain: 0.0, Q: 1.414 (the default Q)

As currently set with Q at 1.414, it actually looks like it's boosting treble a few db before a steep rolloff. I tried messing around with gain and Q settings to see if I could approximate a graph that looked like his, but I'm pretty much in the dark. Adjusting gain doesn't seem to do anything. Adjusting the Q radically shifts the behavior of the rolloff. At 1.414 it boosts treble, then rolls off fast. At 1.0, it has a minor treble boost, followed by a slightly slower rolloff. At 0.9, it actually looks pretty close to Amir's graph, just a faint treble bump. At 0.8, it looks the closest I can find to Amir's, and any lower than that starts to roll off much sooner. I tried it set at 0.1, and the rolloff started at like 250hz.

Can anyone explain what I'm actually adjusting when I adjust the Q this way for a low pass filter? And how should be setting it to achieve 0dB/octave? For now I'm eyeballing it and leaving the Q at .8, but I'll admit I have no idea what I'm doing.

I'm pretty sure you want a low shelf filter, not a low pass.
 

ishouldbeking

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I'm pretty sure you want a low shelf filter, not a low pass.

I would have thought so, but in this case Amir used a LPF. Here's what I'm trying to replicate:

1611346661382.png
 

ishouldbeking

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The second post in every Amir review is a member with Anime profile pic that gives the settings for APO equalizer.

There you will find the settings that will better match Quadelix.

Hmmm. I went looking for it, but it doesn't look like anyone posted that. I've seen those in the headphone review threads for sure. Someone else posted a much more surgical EQ profile that I've also been experimenting with, but I was curious about Amir's settings too. I did notice later in the thread that he mentioned the EQ slope is actually 6dB/octave, which makes more sense to my amateur brain than 0dB/octave that's shown in the image.
 

abdo123

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Hmmm. I went looking for it, but it doesn't look like anyone posted that. I've seen those in the headphone review threads for sure. Someone else posted a much more surgical EQ profile that I've also been experimenting with, but I was curious about Amir's settings too. I did notice later in the thread that he mentioned the EQ slope is actually 6dB/octave, which makes more sense to my amateur brain than 0dB/octave that's shown in the image.

Can you link me to the review?
 

BostonJack

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I have been playing with the Qudelix and just received a custom cable to drive my Drop HD6XX (HD650 variant) which are not the easiest headphone to drive. I use a 2.5 mm TRRS (balanced) to XLR 4 pin balanced cable with Qudelix set to balanced output, performance.

Wow! This little thing drives the HD6XX wonderfully loud with zero obvious audio defects. Moving to balanced was definitely worth it.

I'm going to acquire another XLR 4-pin headphone cable for my Drop Hifi Man 4xx headphones (they are easier to drive than HD650). I already have a 1/4" TRS single-ended to 4-pin XLR adapter. So with two adapter short cables and XLR 4pin headphone cables, I will be able to drive either of my primary headphones from any of my headphone amps and Qudelix.

I haven't played with PEQ much. The HD6XX sound lovely un-eq'ed, to my ears.
 

ishouldbeking

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I have been playing with the Qudelix and just received a custom cable to drive my Drop HD6XX (HD650 variant) which are not the easiest headphone to drive. I use a 2.5 mm TRRS (balanced) to XLR 4 pin balanced cable with Qudelix set to balanced output, performance.

Wow! This little thing drives the HD6XX wonderfully loud with zero obvious audio defects. Moving to balanced was definitely worth it.

I'm going to acquire another XLR 4-pin headphone cable for my Drop Hifi Man 4xx headphones (they are easier to drive than HD650). I already have a 1/4" TRS single-ended to 4-pin XLR adapter. So with two adapter short cables and XLR 4pin headphone cables, I will be able to drive either of my primary headphones from any of my headphone amps and Qudelix.

I haven't played with PEQ much. The HD6XX sound lovely un-eq'ed, to my ears.
I was in love with the 6xx before I started experimenting with EQ... but you should absolutely try it. Our ears compensate for a lot of the minor issues with the stock tuning, but there's actually a fair amount of weird high treble on the 6xx that registers as a kind of fizzy background noise (I never noticed it until I realized how much better it sounded with it EQ'd out). And you will be amazed how much more balanced these sound with some proper sub-bass dialed in and a bit more treble where it's currently lacking. Massive sound improvement to my ears, and like you, I already liked the 6xx a lot. Check Amir's HD650 review thread; Amir's profile is a great starting point. (I've tried Oratory's, AutoEQ's, Maiky's, and a few others, but I wound up liking Amir's the best, with one tweak: I pull down 2dB at 175hz, 1.414 Q, to mitigate the upper-bass bloat).
 

BostonJack

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I was in love with the 6xx before I started experimenting with EQ... but you should absolutely try it. Our ears compensate for a lot of the minor issues with the stock tuning, but there's actually a fair amount of weird high treble on the 6xx that registers as a kind of fizzy background noise (I never noticed it until I realized how much better it sounded with it EQ'd out). And you will be amazed how much more balanced these sound with some proper sub-bass dialed in and a bit more treble where it's currently lacking. Massive sound improvement to my ears, and like you, I already liked the 6xx a lot. Check Amir's HD650 review thread; Amir's profile is a great starting point. (I've tried Oratory's, AutoEQ's, Maiky's, and a few others, but I wound up liking Amir's the best, with one tweak: I pull down 2dB at 175hz, 1.414 Q, to mitigate the upper-bass bloat).

Good advice. I will pursue it. I agree, you should be king.
 

rcmo

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Qudelix has been a game changer to me. Even with some TOTL iems I really enjoy to eq a bit, usually to stick close to Harman’s, sometimes to better fit my mood.

I use an iPhone as my DAP and tried (almost ?) every available player out there. Neutron player is great for equing but otherwise is a pain for offline listening (let alone the UI). I currently use Plexamp.

SQ-wise I wouldn’t say Qudelix changed much but it drives some of the less sensitive item effortlessly and any of my headphones using the balanced output.

Both the device and the app work great. I really appreciate the app, no frills, easy to use, really responsive and a lot of control over the available features.

Really happy and thought I should share.

PS: Fiio BTR5 for sale ;-)
 

m_g_s_g

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I've ordered a "Lightning to Type-C OTG Cable" to use the 5K as an external DAC for my iPad, and it will take some time to arrive. I'll report back.
It took some time to arrive and I forgot to report back :). It works perfectly. Switching between AAC Bluetooth and USB DAC is not fast enough to make a meaningful AB test. (Subjectively it sounds cleaner). But the main point is that the dongle can be charged from the iPad.
 

Palfim

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I had an interesting observation today with my q5.(my first ground loop I think?) I was listening on my fh3 just like many times before, and plugged it into the usb powerline to charge while listening because I was low on battery.
As soon as I plugged it in the USB wall socket, I had a medium loud and easy to hear humming sound, which was just as audible on any volume..like an extra instrument , but it's volume actually stayed the same no matter the q5 total volume, but you could always hear the humm clearly, which basically made listening while charging impossible.

After plugging it out of the wall socket, the humming disappeared . Then I tried to just touch the metal plug from the the headphone cable and it was gone, too! (while being plugged into wall socket again) ! So I figured it must be a grounding issue.

I tried to reproduce it with a similar sensitive IEM (both on single ended)but this humming only happend on the fh3.

So I guess the fault lies within the cable ? Unfortunately I didn't have a balanced one for comparison , but my other IEM has a balanced cable to which I attached an adapter (That really small transparent DD one) to make it single ended, still no humm like on the fh3. And have I mentioned that the cable looks like a very good quality one?

From the lurking I did on here, I figured a new balanced cable could get rid of ground loops while charging , am I correct on this one? Maybe the whole house isn't grounded very well (50 residents). But I never payed attention to such humms and just figured it's the gear itself which just doesn't sound that clear haha.
Now when I listen on battery mode only, I get an absolut black background no noise, hiss , humm or such stuff, only music
 

Rottmannash

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I had an interesting observation today with my q5.(my first ground loop I think?) I was listening on my fh3 just like many times before, and plugged it into the usb powerline to charge while listening because I was low on battery.
As soon as I plugged it in the USB wall socket, I had a medium loud and easy to hear humming sound, which was just as audible on any volume..like an extra instrument , but it's volume actually stayed the same no matter the q5 total volume, but you could always hear the humm clearly, which basically made listening while charging impossible.

After plugging it out of the wall socket, the humming disappeared . Then I tried to just touch the metal plug from the the headphone cable and it was gone, too! (while being plugged into wall socket again) ! So I figured it must be a grounding issue.

I tried to reproduce it with a similar sensitive IEM (both on single ended)but this humming only happend on the fh3.

So I guess the fault lies within the cable ? Unfortunately I didn't have a balanced one for comparison , but my other IEM has a balanced cable to which I attached an adapter (That really small transparent DD one) to make it single ended, still no humm like on the fh3. And have I mentioned that the cable looks like a very good quality one?

From the lurking I did on here, I figured a new balanced cable could get rid of ground loops while charging , am I correct on this one? Maybe the whole house isn't grounded very well (50 residents). But I never payed attention to such humms and just figured it's the gear itself which just doesn't sound that clear haha.
Now when I listen on battery mode only, I get an absolut black background no noise, hiss , humm or such stuff, only music

No clue if this is related but I had my Hiby R5 in the car and the battery was running low so plugged the USB C cable into the unit and the 12V socket in my car to charge and immediately heard a buzzing sound-I unplugged the USB C cable from the R5 and it stopped, so it appears some of these devices don't like to be charged while they are in operation.
 
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