Neutron Hifi DAC V1

[CedarX]

Very interesting, but the Qudelix 5K, which is $70 cheaper, has a battery, balanced 4VRMS output and already 20 bands / LR PEQ.

Both have ES9219 DAC chips, which makes me wonder a bit how much of an advantage this Neautron Hifi Dac V1 has.

Don’t disagree with your assessment, but the battery may be seen as a big negative by some, and the 5K did not measure great as an USB DAC/Amp (due to the use of the QCC5124 as USB bridge?).
FiiO is another option.

 

[rlw6534]

Don’t disagree with your assessment, but the battery may be seen as a big negative by some, and the 5K did not measure great as an USB DAC/Amp (due to the use of the QCC5124 as USB bridge?).
FiiO is another option.

A small, low power drain USB powered DAC with PEQ is what appeals to me. I have the Q5K as well but it is still a bit cumbersome as a USB dongle. Of course I like new toys also...

 

[GaryH]

the 5K did not measure great as an USB DAC/Amp

It's audibly transparent.

 

[koustuvk17]

It's audibly transparent.

Plus there has been an update since the review adding a new "distortion compensation" option. I don't think anyone has measured the numbers with it activated.

 

[neutroncode]

Today Apple approved NConfigurator in App Store (https://apps.apple.com/app/nconfigurator/id6501984120). It simplifies DAC V1's configuration on Macs - no more fiddling with Privacy & Security settings.

 

[neutroncode]

Aa per earlier discussion here DAC V1's received Firmware 40 update today which expands its DSP capabilities:

* Support for 20-band per-channel Parametric EQ (PCM frequency is limited up to 96 kHz)
* Support for DSP effects chaining, e.g.: EQ [10B] + Crossfeed, EQ [10B] + FRC, FRC + Crossfeed (PCM frequency is limited up to 96 kHz)

Release details are on Neutron Forum's dedicated forum.

After carefully checking MCU performance the only limitation applied is max 96 kHz PCM frequency in case of 20-band PEQ or effect chaining (>1 active effects).

NConfigurator tool was updated too to reflect this advancement and its version is now 1.6.0. Released on Neutron HiFi web-site as usually + Apple App Store version is pending the review [update: Apple approved it now, so it is live].

NConfigurator now also supports saving and loading EQ presets into/from a file, therefore it is very convenient to exchange with presets, backup own and etc.

DAC V1 supports such DSP modes:

• Off
• Crossfeed
• Frequency Response Correction (FRC)
• Frequency Response Correction (FRC) + Crossfeed
• Equalizer (EQ) [10B]
• Equalizer (EQ) [10B] + Crossfeed
• Equalizer (EQ) [10B] + Frequency Response Correction (FRC)
• Equalizer (EQ) [20B]

 

[Robbo99999]

Aa per earlier discussion here DAC V1's received Firmware 40 update today which expands its DSP capabilities:

* Support for 20-band per-channel Parametric EQ (PCM frequency is limited up to 96 kHz)
* Support for DSP effects chaining, e.g.: EQ [10B] + Crossfeed, EQ [10B] + FRC, FRC + Crossfeed (PCM frequency is limited up to 96 kHz)

Release details are on Neutron Forum's dedicated forum.

After carefully checking MCU performance the only limitation applied is max 96 kHz PCM frequency in case of 20-band PEQ or effect chaining (>1 active effects).

NConfigurator tool was updated too to reflect this advancement and its version is now 1.6.0. Released on Neutron HiFi web-site as usually + Apple App Store version is pending the review.

NConfigurator now also supports saving and loading EQ presets into/from a file, therefore it is very convenient now to exchange with presets, backup own and etc.

DAC V1 supports such DSP modes:

• Off
• Crossfeed
• Frequency Response Correction (FRC)
• Frequency Response Correction (FRC) + Crossfeed
• Equalizer (EQ) [10B]
• Equalizer (EQ) [10B] + Crossfeed
• Equalizer (EQ) [10B] + Frequency Response Correction (FRC)
• Equalizer (EQ) [20B]

Nice, good job! Did you say you were gonna send Amir one to review? (Seeing as you've got this latest update released, then I guess it's a good time.)

 

[neutroncode]

Nice, good job! Did you say you were gonna send Amir one to review? (Seeing as you've got this latest update released, then I guess it's a good time.)

Yes, I already PMed @amirm about it today.

 

[neutroncode]

Then measure the coupling capacitance with an LCR meter between USB input and USB output.

@MC_RME, measured capacitance between USB-C Input and USB-C Output ports is around 22-24pF for the just produced 2 test Isolator V1 boards. It is quite low. In general, parasitic capacitance shall not affect audio performance of the connected USB DAC if its internal parts are powered via LDOs.

 

[MC_RME]

@MC_RME, measured capacitance between USB-C Input and USB-C Output ports is around 22-24pF for the just produced 2 test Isolator V1 boards

Thumbs up! That is very good.

In general, parasitic capacitance shall not affect audio performance of the connected USB DAC if its internal parts are powered via LDOs.

Correct, but that's not the point. The user experiences leakage/grounding current effects at the output of the DAC which make him think the noise is from the DAC - when it isn't. Welcome in hardware support wonderland...

 

[neutroncode]

Want to highlight new coming DSP feature. In addition to recently listed DSP capabilities DAC V1 will get Surround DSP (based on Ambiophonics R.A.C.E. which is used by Neutron Player) in the next fw update. It is to address DAC V1's user wishes and scenario of using DAC V1 with external speakers. According to CPU load it can be paired with 10-band EQ or FRC, similarly to Crossfeed.

 

[Robbo99999]

Want to highlight new coming DSP feature. In addition to recently listed DSP capabilities DAC V1 will get Surround DSP (based on Ambiophonics R.A.C.E. which is used by Neutron Player) in the next fw update. It is to address DAC V1's user wishes and scenario of using DAC V1 with external speakers. According to CPU load it can be paired with 10-band EQ or FRC, similarly to Crossfeed.

What's the Surround DSP like? I'm assuming the DAC won't appear as a multi-channel device to Windows, ie it will still appear as a stereo 2-channel device?

 

[neutroncode]

Ambiophonics R.A.C.E. is not the surround DSP which creates multiple channels (Wiki: https://en.wikipedia.org/wiki/Ambiophonics). This DSP creates the surround effect based on 2 channels and is opposite effect to Crossfeed DSP.

You can easily test it if you have Neutron Player and there there:

• Playback -> DSP Effect -> Surround Sound = On
• Playback -> DSP Effect -> Stereo Effect -> Surround Sound =On

DAC V1 will gain the same DSP as in Neutron Player but then it can be used with any audio source.

 

[Robbo99999]

Ambiophonics R.A.C.E. is not the surround DSP which creates multiple channels (Wiki: https://en.wikipedia.org/wiki/Ambiophonics). This DSP creates the surround effect based on 2 channels and is opposite effect to Crossfeed DSP.

You can easily test it if you have Neutron Player and there there:

• Playback -> DSP Effect -> Surround Sound = On
• Playback -> DSP Effect -> Stereo Effect -> Surround Sound =On

I see, thanks. It's a lot to ask as it could be quite a niche product, but if your DAC did everything it currently does with it's 20 band parametric EQ but then combined with it being seen as a multichannel DAC (say 7.1) that was combined with a good virtual surround implementation as good as Creative SBX then this would be the end game DAC for me to buy for my PC for my combined gaming/music/headphone EQ needs! I mean we're talking a different product here, but that would be my ideal, but I don't know how many people would demand such a thing, might be a bit niche.

 

[CedarX]

I see, thanks. It's a lot to ask as it could be quite a niche product, but if your DAC did everything it currently does with it's 20 band parametric EQ but then combined with it being seen as a multichannel DAC (say 7.1) that was combined with a good virtual surround implementation as good as Creative SBX then this would be the end game DAC for me to buy for my PC for my combined gaming/music/headphone EQ needs! I mean we're talking a different product here, but that would be my ideal, but I don't know how many people would demand such a thing, might be a bit niche.

The Qudelix T71 could become this end game DAC… It has 8 channels, but not much to offer in term of virtual surround sound (yet?). It certainly has capable CPU/DSP hardware.

 

[Robbo99999]

The Qudelix T71 could become this end game DAC… It has 8 channels, but not much to offer in term of virtual surround sound (yet?). It certainly has capable CPU/DSP hardware.

It does say this about it though, but I'm thinking it would all depend on the "proprietary down-mixing algorithm" they mention, I mean that should be Virtual Surround Sound otherwise they'd be no point in it receiving 7.1 in the first place:

Discrete 7.1CH Surround​

• 
  7.1CH USB DAC Mode
• 
  Max. 96KHz / 32-bit / 7.1CH
• 
  Channel Independent DSP(Digital Signal Processing)
• 
  Proprietary Down-Mixing Algorithm

EDIT: found some more information on it:

Qudelix-T71

Discrete 7.1 Surround USB DAC The Qudelix-T71 is a USB DAC (Digital-to-Analog Converter) that is designed to receive and process multi-channel audio from a host source device. Unlike most conventional USB DACs that only receive two-channel stereo audio, the T71 can receive up to 8 channels of...

www.qudelix.com

It does do Virtual Surround Sound processing but they're not making a big deal about that, which makes me think it's not very good. But they also offer a T71 IEM that has got a number of "real" surround sound drivers built into the IEM (so their IEM is an actual 7.1 device itself, a driver for each channel) which is designed to be used with the T71 DAC, but God knows how that could ever work successfully.

 

[neutroncode]

if your DAC did everything it currently does with it's 20 band parametric EQ but then combined with it being seen as a multichannel DAC (say 7.1) that was combined with a good virtual surround implementation as good as Creative SBX then this would be the end game DAC

Currently 20-band PEQ in DAC V1 takes quite a lot of CPU time, so probably 7.1 -> 2 downmixing with preservation of spatial effect of rear and side channels (it is what we would expect from Gaming mode when game/app is placing sounds around the listener) will be too much for CPU with 20-band PEQ.

I will put into to-do to analyze this feature and evaluate whether CPU of DAC V1 allows to do high quality downmixing of 7.1 -> 2 with preservation of surround effect coming from rear + side channels. Gaming mode/7.1 downmixing was not considered initially because in practice it is impossible to simulate real surround effect we get with 7.1 audio system with headphones which send purely directional sound to our ears. There is no algorithm which can simulate surround effect in headphones because in practice all this is limited by elementary physics, maybe algorithm can emulate to some subtle degree but the result will be very subjective (some would not hear any 3D effect at all due to personal perception of sound and hearing).

Therefore, delivery something which would be questionable was not on a roadmap, but DAC V1 is driven by user wishes and requests, so why not trying 7.1 -> 2.0 with Surround too. Here the main factor in play will be available CPU time needed for DSP for preserving the surround clues from side + rear channels.

 

[piaseczek]

Thumbs up! That is very good.



Correct, but that's not the point. The user experiences leakage/grounding current effects at the output of the DAC which make him think the noise is from the DAC - when it isn't. Welcome in hardware support wonderland...

So the new neutron is better than hifime (70pF). Interesting product.

Hifime Hi-Speed USB Isolator v2

The Hifime High-Speed USB Isolator is designed specifically for audio and supports USB Hi-speed mode that is required by many Audio devices. It will prevent ground loops, prevent interference and protect your equipment against power surges.

hifimediy.com

 

[piaseczek]

@MC_RME, measured capacitance between USB-C Input and USB-C Output ports is around 22-24pF for the just produced 2 test Isolator V1 boards. It is quite low. In general, parasitic capacitance shall not affect audio performance of the connected USB DAC if its internal parts are powered via LDOs.

Will there be a preorder promotion?

 

[Robbo99999]

Currently 20-band PEQ in DAC V1 takes quite a lot of CPU time, so probably 7.1 -> 2 downmixing with preservation of spatial effect of rear and side channels (it is what we would expect from Gaming mode when game/app is placing sounds around the listener) will be too much for CPU with 20-band PEQ.

I will put into to-do to analyze this feature and evaluate whether CPU of DAC V1 allows to do high quality downmixing of 7.1 -> 2 with preservation of surround effect coming from rear + side channels. Gaming mode/7.1 downmixing was not considered initially because in practice it is impossible to simulate real surround effect we get with 7.1 audio system with headphones which send purely directional sound to our ears. There is no algorithm which can simulate surround effect in headphones because in practice all this is limited by elementary physics, maybe algorithm can emulate to some subtle degree but the result will be very subjective (some would not hear any 3D effect at all due to personal perception of sound and hearing).

Therefore, delivery something which would be questionable was not on a roadmap, but DAC V1 is driven by user wishes and requests, so why not trying 7.1 -> 2.0 with Surround too. Here the main factor in play will be available CPU time needed for DSP for preserving the surround clues from side + rear channels.

Hey, well that's great that you can take a look to see if Virtual Surround is implementable! I wasn't expecting that. From my own point of view 48kHz would be optimal for use with Virtual Surround gaming, as most games are in 48kHz last time I looked, and from what you were saying earlier in the thread then limiting it to 48kHz might save you some additional CPU cycles. I agree that Virtual Surround in headphones doesn't work for everyone, but it does work for me & some others I have discussed with on forums & gaming lobbies, but for instance it's only the Creative SBX that works for me - I've tested audio files that have been created using quite a few of the existing Virtual Surround tech out there, and it was only Creative SBX that works for me, and only at a specific setting on their Surround Variable, which can be set from 0-100 for that variable, and there's only a small window that works for me in that setting - the way they work it is the value you choose from 0-100 changes the position of the virtual speakers, that's what I've found. So you might find it challenging to create a Virtual Surround that works for everyone, and I couldn't be sure it would work for me until I test it. Following is a thread on 7.1 Virtual Surround that I created, and there's a 7.1 test file that I use to fine tune & test my Virtual Surround Sound (listed in first post of following thread):

Virtual 7.1 Surround Sound processing in Headphones

Hi, I thought I'd start this thread as a gaming virtual 7.1 surround sound enthusiast in headphones. We can let this thread develop into whatever we like on the topic of Virtual 7.1 Surround Sound processing in headphones, and perhaps I'll continue to edit this first post with links to useful...

www.audiosciencereview.com

It's possible you might find that approach to testing useful when you're thinking about your implementation of Virtual Surround Sound. Whatever happens it's crucial that the DAC is seen as a 7.1 device in Windows, that way it can take 7.1 channel information from the game and then the DAC does it's magic to convert it into Virtual speakers in your headphones. (Windows Sonic & Dolby Atmos Headphones didn't work for me, but Creative SBX did.). It's also crucial that there is close to "zero latency" associated with the audio processing & delivery, as gaming sound cues can be vital in a first quick reaction to a situation (and of course the sound cues have to line up with what you're seeing on the screen in terms of latency would kill realism of gun shots in first person shooters for instance). I might be able to help you test the effectiveness of your Virtual Surround Sound implementations if you like - in terms of what works for me at least.

(Maybe limiting PEQ to 10 band on each channel (left & right driver), and whilst limiting to 48kHz might give enough overhead for virtual surround processing, as an idea.)
(Maybe it would be useful to have a configuration setting for putting the DAC into 5.1 mode or 7.1 mode, as some games might not do 7.1 for instance, but I'd say 7.1 is the main one.)