Neutron HiFi DAC V1 Review

[CedarX]

I hope this new functionality will make interaction with the DAC V1 even more interesting and exciting

A unique feature, definitely interesting to me. Add this to the list of DAC V1 features and… I couldn’t resist: just ordered a DAC V1!

 

[migo77]

It is shame that there is no desktop DAC with functionality like Neutron DAC and remotely controlled by mobile app like Qudelix 5k DAC. That will me my dream setup for PRi streamer.

 

[dmitrykos]

It is shame that there is no desktop DAC with functionality like Neutron DAC and remotely controlled by mobile app like Qudelix 5k DAC. That will me my dream setup for PRi streamer.

With time being all can be possible

For now, active development is happening on simultaneously mobile + web version of NConfigurator. Here is a screenshot of the initial working version on Android device with DAC V1 connected to it:

It is not a pure mobile app. Mobile app is running the native NConfigurator core which acts as USB interface to the connected DAC V1 and as a HTTP server for the Web API, it also runs web view (GUI) of the web-app being developed in Angular - 3 roles in total. Web-app is served by nconf.neutronhifi.com externally.

Once completed, NConfigurator (any version, including PC) will be able to run as HTTP daemon, so you will be able to run it as service on some headless mini-PC serving as audio streamer via DAC V1. It then can be accessed with a web browser from any other device.

Of course, you will be able to just install Android version of NConfigurator from Google Play and access DAC V1 connected to this Android device, above is just the extended usage scenario.

 

[migo77]

With time being all can be possible

For now, active development is happening on simultaneously mobile + web version of NConfigurator. Here is a screenshot of the initial working version on Android device with DAC V1 connected to it:

View attachment 429168

It is not a pure mobile app. Mobile app is running the native NConfigurator core which acts as USB interface to the connected DAC V1 and as a HTTP server for the Web API, it also runs web view (GUI) of the web-app being developed in Angular - 3 roles in total. Web-app is served by nconf.neutronhifi.com externally.

Once completed, NConfigurator (any version, including PC) will be able to run as HTTP daemon, so you will be able to run it as service on some headless mini-PC serving as audio streamer via DAC V1. It then can be accessed with a web browser from any other device.

Of course, you will be able to just install Android version of NConfigurator from Google Play and access DAC V1 connected to this Android device, above is just the extended usage scenario.

Thank you! I cant wait for it! Web based management is the way to go without ability to control DAC V1 over BT. It will serve as my desktop DAC connected to RPi streamer and amp. 5V balanced output can add dynamic range, but this another story maybe sometimes in future.

 

[CedarX]

With time being all can be possible

For now, active development is happening on simultaneously mobile + web version of NConfigurator. Here is a screenshot of the initial working version on Android device with DAC V1 connected to it:

View attachment 429168

It is not a pure mobile app. Mobile app is running the native NConfigurator core which acts as USB interface to the connected DAC V1 and as a HTTP server for the Web API, it also runs web view (GUI) of the web-app being developed in Angular - 3 roles in total. Web-app is served by nconf.neutronhifi.com externally.

Once completed, NConfigurator (any version, including PC) will be able to run as HTTP daemon, so you will be able to run it as service on some headless mini-PC serving as audio streamer via DAC V1. It then can be accessed with a web browser from any other device.

Of course, you will be able to just install Android version of NConfigurator from Google Play and access DAC V1 connected to this Android device, above is just the extended usage scenario.

Do you think NConfigurator could be embedded onto something like a ESP32?
Then… could a version of USB isolator include this ESP32 (or else) HTTP server as an added feature? USB isolator would become the desktop host for DAC V1…

Or am I just dreaming too much? (Very possible! )

 

[dmitrykos]

Do you think NConfigurator could be embedded onto something like a ESP32?
Then… could a version of USB isolator include this ESP32 (or else) HTTP server as an added feature? USB isolator would become the desktop host for DAC V1…

ESP32 (S2/S3) are Full-Speed USB MCUs, so will not serve in this scenario as DAC V1 is a High-Speed USB device (primarily). Also, such idea looks too complicated because Isolator V1 must simulate self as USB DAC to US Host (PC for example) to collect audio USB packets from it and then on 2-nd USB port (outbound) it has to behave as USB host for DAC V1 and feed received USB data from PC. Normally USB isolator is not seen by PC as USB device, it just replays USB packets with specialized IC (making USB data transmission isolated) and generates isolated DC power. So when you connect some USB client to Isolator V1 for example, then USB Host (PC) sees connected USB device as if it is connected by the cable directly to PC.

Better and much simpler just develop new USB DAC (stationary in this case) with isolated USB port and WiFi capability onboard. Then MCU/CPU of the device will host NConfigurator, WiFi/LAN would serve Web API of NConfigurator and isolated port will substitute Isolator V1.

 

[migo77]

ESP32 (S2/S3) are Full-Speed USB MCUs, so will not serve in this scenario as DAC V1 is a High-Speed USB device (primarily). Also, such idea looks too complicated because Isolator V1 must simulate self as USB DAC to US Host (PC for example) to collect audio USB packets from it and then on 2-nd USB port (outbound) it has to behave as USB host for DAC V1 and feed received USB data from PC. Normally USB isolator is not seen by PC as USB device, it just replays USB packets with specialized IC (making USB data transmission isolated) and generates isolated DC power. So when you connect some USB client to Isolator V1 for example, then USB Host (PC) sees connected USB device as if it is connected by the cable directly to PC.

Better and much simpler just develop new USB DAC (stationary in this case) with isolated USB port and WiFi capability onboard. Then MCU/CPU of the device will host NConfigurator, WiFi/LAN would serve Web API of NConfigurator and isolated port will substitute Isolator V1.

Maybe I'll be lucky and see balanced outs on this stationary device ) Packed with features like V1 and excellent support from you that device will have no contenders, maybe one - RME, but this is another price range. Support is the key here, I think.

Topping devices measure excellently but have lot of unresolved problems and support is very limited even for high-end (expansive) one. They are replaced with newer models and buyers are left alone without help.

Qudelix5k is the exact opposite, my device is more than 4y old and still getting updates and new features! = happy user! And my current desktop setup looks like:

 

[migo77]

@dmitrykos How are Intersample Overs processed in DACv1? Hopefully it is not bothering question, I'm sure you, with your skills have take care of it. Thank you.

 

[dmitrykos]

@dmitrykos How are Intersample Overs processed in DACv1? Hopefully it is not bothering question, I'm sure you, with your skills have take care of it. Thank you.

There is no clipping in DAC V1 at all frequencies, otherwise we would measure a distortion (obviously) and so high precision would not be achieved in the benchmark of the review and own measurements. Oversampling Filter's 2-nd stage normalizes gain so that it would not exceed max in digital domain. Furthermore you have Impedance presets in NConfigurator which engage (or not) Master Trim setting of the DAC chip to avoid clipping in analog domain.

 

[migo77]

There is no clipping in DAC V1 at all frequencies, otherwise we would measure a distortion (obviously) and so high precision would not be achieved in the benchmark of the review and own measurements. Oversampling Filter's 2-nd stage normalizes gain so that it would not exceed max in digital domain. Furthermore you have Impedance presets in NConfigurator which engage (or not) Master Trim setting of the DAC chip to avoid clipping in analog domain.

Thank you, to be safe from bad recorded music with intersample overs it is recommended to run -3dB from max volume when operating as desktop DAC connected to AMP. Right?

 

[joncl]

I'm am looking for a DAC with EQ, and this appears to be an amazing product. My use is mostly for the desktop (stationary). I see the profile feature is now available which is great. How can a EQ profile be switched easily in Windows? Would be great to have a pop-up from a task tray icon with a list of saved profiles to pick from. Or perhaps this is available already? Also, maybe even better, is there a way to switch profiles from a command line?

 

[dmitrykos]

Thank you, to be safe from bad recorded music with intersample overs it is recommended to run -3dB from max volume when operating as desktop DAC connected to AMP. Right?

If you are not using any DSP which can equalize digital representation of the audio wave then you do not need that headroom (-3 dB). When music player app is reading/decoding music file the data in it is already truncated/clamped to the valid digital range, for simplicity let's say [-1.0, 1.0]. So if no processing is done on this data then it will not cause any overloading in digital domain and DAC chip will also output non-clipped analog wave. It must happen like this.

But, if there are errors in music player app, for example it converts from floating point to integer representation and does not clamp values to the valid range then overloading can happen in digital domain. If hardware design has flaws then it can also can cause clipping in analog output, or maybe there is no THD setting via some app like NConfigurator for DAC V1 which corrects master volume of the DAC chip for the impedance of the connected headset.

So there is no general rule for -3 dB thing to my view, if you really hear overloaded sound then decreasing master gain to some value which stops this behavior is a good idea.

 

[dmitrykos]

How can a EQ profile be switched easily in Windows? Would be great to have a pop-up from a task tray icon with a list of saved profiles to pick from. Or perhaps this is available already? Also, maybe even better, is there a way to switch profiles from a command line?

Currently, Profile can be switched via NConfigurator's GUI like this:

Switching from the task tray is a good idea and I added it into to-do for the future updates. From the command line not supported either in 1.7.4 but will expose such possibility in the future updates too. Once mobile/web version is released (soon) you will also be able to switch profile via the web interface while NConfigurator is running in background.

 

[migo77]

If you are not using any DSP which can equalize digital representation of the audio wave then you do not need that headroom (-3 dB). When music player app is reading/decoding music file the data in it is already truncated/clamped to the valid digital range, for simplicity let's say [-1.0, 1.0]. So if no processing is done on this data then it will not cause any overloading in digital domain and DAC chip will also output non-clipped analog wave. It must happen like this.

But, if there are errors in music player app, for example it converts from floating point to integer representation and does not clamp values to the valid range then overloading can happen in digital domain. If hardware design has flaws then it can also can cause clipping in analog output, or maybe there is no THD setting via some app like NConfigurator for DAC V1 which corrects master volume of the DAC chip for the impedance of the connected headset.

So there is no general rule for -3 dB thing to my view, if you really hear overloaded sound then decreasing master gain to some value which stops this behavior is a good idea.

Thank you or detailed explanation. I'm using UAPP app to play bit-perfect to DAC. But some songs are recorded in wrong way, not respecting specs for audio mastering. I'm referencing to this article for example:

Intersample Overs in CD Recordings

Intersample Overs are a Common Occurrence in CD Recordings We have frequently used Steely Dan's Gaslighting Abbie from Two Against Nature in our listening tests. This is a spectacular CD recording with lots of dynamics and a low noise floor. Nevertheless, in a little over 5 minutes, this track...

benchmarkmedia.com

 

[dmitrykos]

But some songs are recorded in wrong way, not respecting specs for audio mastering.

For the DAC chip there is no wrong audio data. It just converts digital to analog representation and how digital representation is structured does not really matter. If artifacts appear, such as those discussed in the article you quoted, then it can be a flaw either in software (for example buggy software resampler) or hardware (clipping).

1) Here is the waveform view of the recording of 44.1 kHz sweep tone (1 - 22050 Hz) made with DAC V1 using THD preset for 32 Ohm load and set to 100% volume. I selected area of approx. [20, 20000] Hz. In this case DAC chip is doing 8x Oversampling to achieve 352800 Hz before data goes to chip's Modulator. As you can see 20-20000 range is linear and does not exhibit any fluctuations or overloading.



2) Here is recording of 88.2 kHz sweep tone (1 - 44100 Hz) made with DAC V1 using the same settings. The [20, 20000] Hz range is approximately 1/2 of the plot but it is the same linear and amplitude of the wave equals to 44.1 kHz case. Here DAC chip is doing 4x Oversampling and nothing really changed in comparison to 8x, that means and confirms that Oversampling does not cause issues discussed in that article.



To my view the authors of the article were facing clipping in analog domain and mistakenly assumed that Oversampling is the reason. Instead, they would better introduce possibility to apply THD preset for different load/impedance case which in case of ESS DAC chip has Master Trim parameter which decreases audio volume before data is sent to Modulator of the chip.

 

[dmitrykos]

NConfigurator for Android is out! Currently, available for download from Neutron HiFi web site and later will go to Google Play:

https://neutronhifi.com/download/tool/NConfiguratorGooglePlay.apk

There is Demo mode (tap Demo button instead of Connect) for those guys without DAC V1 but willing to check out the functionality. Demo mode does not store any changes but allows to browse all sections of NConfigurator app and toggle options.

This app is based on Android-app + Web-app. Web-app is available via https://nconf.neutronhifi.com and will later allow connection to DAC V1 within local network with NConfigurator running as HTTP server (currently released version can't do it but new release will follow soon).

Any comments regarding functionality are welcome.

 

[dmitrykos]

NConfigurator 1.8.1 is out on PC platforms, so now you can try controlling DAC V1 remotely via the web app interface http://nconf.neutronhifi.com

Inside web interface before clicking Connect, first click 3-dot button and select Custom Address, then fill in the IP of the remote machine with connected DAC V1 to it.

Release notes:

NConfigurator 1.8.1 - Neutron Forum