[lionel marechal]

I am looking for a DAC/Amp (a la Matrix mini, audio gd, ...) , 200-400$ max, that would be work directly though USB with my synology NAS. Smaller like HRT microstreamer are candidates as well (would it work?).
 
Compatible :
I have an old edirol UA25 and a HPDAC (built by misterX) that work well.
I believe all the GD audio (prior to USB32 update) are working, but I am unsure.
 
Not compatible:
I was looking at the TEAC UD H01, but read that its not compatible.
 
If you have experienced one way or another and could share your experience, that would be grea!
 
Lionel
 
Compatible DACs - Update 5/30/2013
Edirol UA 25 (Own)
HPDAC (w)
Audioquest Dragonfly (head-fi)
Music Streamer II (head-fi)
Peachtree audio nova (Forum Audiophile)
Odac (Forum Audiophile)
Micromega myDAC (DSM >= 4.2) (Forum Audiophile)

 

[bigtim]

Hi Lionel,

I'm using an Audioquest Dragonfly out of my Synology NAS. It's great for files up to 24-bit/96kHz but anything higher res won't play.

I've got my iTunes library on the NAS accessing it through the DS Audio app. Great stuff

 

[lionel marechal]

I have udpated the list at the top of the thread and will keep it updated.
Lionel
 

 

[musixs]

I think coonnecting your DAC to the USB socket of Synology NAS is not worth it. If I'm not mistaken the Synology is pre equiped with an internal DAC if connected via its USB output.
I just bought DS114 NAS and were trying to connect my Theorem 720 via the Synology USB sockets using their Audio Station apps as the controller. However as it turned out, the volume control in the Audio Station apps was actually functioning when it wasn't supposed to if the Synology were only function as a digital tranporter..
Might be wrong but I think it make sense..

 

[sojs]

What's the advantage of directly connecting to NAS as opposed to going thru PC USB?

 

[Roseval]

I think coonnecting your DAC to the USB socket of Synology NAS is not worth it. If I'm not mistaken the Synology is pre equiped with an internal DAC if connected via its USB output.

Sorry but this is total nonsense.
A DAC is a Digital to Analog Converter.
Nothing analog about USB.
 
Compatible DACs
As usual devices can only communicate if they share the same protocol.
Linux supports UAC1 and UAC2 (USB Audio Class)
 
Obvious Synology supports UAC1 hence all DACs like the Dragonfly (also UAC1) will play.
Don't know if Synology support UAC2 but if it does all DACs not needing a driver for OSX or Linux will play as well

 

[musixs]

 
Compatible DACs
As usual devices can only communicate if they share the same protocol.
Linux supports UAC1 and UAC2 (USB Audio Class)
 
Obvious Synology supports UAC1 hence all DACs like the Dragonfly (also UAC1) will play.
Don't know if Synology support UAC2 but if it does all DACs not needing a driver for OSX or Linux will play as well

 
Please enlight me:
1. Can we amplify digital signals so that they would produce louder sound? OR do we need to convert digital signal to analog format before we could actually hear any audible diference?
 
2. At which point of interface does this signal (Digital? or Analog?) can be amplify?
 
3. On my personal encounter. I connected the USB socket of the Synology DS114 to my DAC/Amp (Theorem 720). I could hear songs out through of the Theorem 720 headphone output. HOWEVER, how is it that the control command (via Ipad) DIRECTED TO THE SYNOLOGY (using Audio Station app) is able to increase/reduce the sound volome out of my headphone?
 
4. Cypherlabs dac/amp if I'm not mistaken able to bypass i-device internal DAC. When I did this to my Ipod-Theorem stack, the volume control on my Ipod simply doesn't work. I believe the ipod is simply functioning as a Digital transporter.
Would that be releveant to this Synology instance..?
 
5. Perhaps a USB/DAC simply able to bypass the Synology's DAC, as Roseval has pointed out. Would that be right?   

 

[musixs]

  What's the advantage of directly connecting to NAS as opposed to going thru PC USB?

 
My experience with the NAS system is new and there are yet other possibilities that I'm still eager to find out. However just like to share some thought on it, which might perhaps be kind of relevant to you as well.
 
For me the idea of streaming digital media out of these devices is wonderful. It simply reduce large portion of the wiring needed on those more conventional audio/video system. However I'm not so sure how does sound quality coming out of this digital streaming differ from the more conventional system.            
 
With this NAS, I think the device could connect to several users and still able to give direct control to different perform tasks at the same time. Would that be possible with a Personal Computer..?

 

[Roseval]

1. Can we amplify digital signals so that they would produce louder sound?
 
In case of a analog signal an amplifier simply produces more juice.
In case of a digital signal we have the samples. We can multiply them with any factor of choice. Note that we don't change the electrical signal, that would fry our chips but change the numerical values of the samples
 
2 At which point of interface does this signal (Digital? or Analog?) can be amplify?
As our audio gear don't understand digital, we need a DAC, a digital to analog converter
Digital volume control must be applied before the conversion, analog volume control can only be applied after the conversion
 
3 That is an example of digital volume control
 
4 Correct, if you bypass the DAC of the iPod simply sends it digital to the receiver
 
5 Of course, you have media player running on the Synology. It sends the digital audio to a device on the bus.. If this is the onboard audio it will be converted to analog there.
If it is a USB port, it send the samples to a USB DAC and they will be converted there.

 

[Roseval]

  With this NAS, I think the device could connect to several users and still able to give direct control to different perform tasks at the same time. Would that be possible with a Personal Computer..?

 
This is called UPnP/DLNA
That is the protocol driven streaming AV
In case of Windows, from Vista on Win is fully DLNA compliant.
You can do exactly the same with a Win PC
In case of OSX, Apple doesn't support DLNA, they have their own proprietary protocol called Airplay

 

[sojs]

I am using Synology NAS and it's connected to my router, so that all my PCs in my house can have access to the music files.

 

[musixs]

 
 

   
This is called UPnP/DLNA
That is the protocol driven streaming AV
In case of Windows, from Vista on Win is fully DLNA compliant.
You can do exactly the same with a Win PC
In case of OSX, Apple doesn't support DLNA, they have their own proprietary protocol called Airplay

 
Interesting..!! will read on this UPnP/DLNA after. 
Never really get in touch of this digital world ever since I passed my Uni. years..
Thanks for sharing dude.. 

 

[musixs]

  1. Can we amplify digital signals so that they would produce louder sound?
 
In case of a analog signal an amplifier simply produces more juice.
In case of a digital signal we have the samples. We can multiply them with any factor of choice. Note that we don't change the electrical signal, that would fry our chips but change the numerical values of the samples
 

 
Hi Roseval, your insight got me intrigued and so I watched some videos at you tube on the subject. Particularly the one by Martin Mallison. 
Since I can't ask Martin on the subject, perhaps I should try with you then. If you don't mind sharing further...
 
Questions for you:
 
1. With the digital volome control. Is it right that to reduce/increase the volume we simply change multiplying factor of the bits by the desired dB change so that the out come is a DIFFERENT BINARY sequence ??
 
2. If the above assumption is correct, would that means we have simply altered the digital signals not to the original sequence the records intended to be?
 
3. By supposed if we were to change the amplitude of the signal would it be "better" if we do it in an analog volume control after..? ("better" in a sense less alteration and thus higher fidelity of the recording to the signal outcome ??)
 
Thanks Roseval.. Hope you don't mind with the extended discussion...     

 

[Roseval]

ad 1: we do change the value of the samples. That is inherent to any kind of DSP
ad 2: we do so on the fly hence what we send to the DAC will differ from the recording if that is what you mean to say.
ad 3: by design we lose some of the dynamic range but if this is damaging is a different question. Modest digital volume control is in general not audible.
You found Mallison already. There is a likewise paper on the subject by ESS: http://www.esstech.com/PDF/digital-vs-analog-volume-control.pdf
 
Best
 
Vincent

 

[musixs]

  ad 1: we do change the value of the samples. That is inherent to any kind of DSP
ad 2: we do so on the fly hence what we send to the DAC will differ from the recording if that is what you mean to say.
ad 3: by design we lose some of the dynamic range but if this is damaging is a different question. Modest digital volume control is in general not audible.
You found Mallison already. There is a likewise paper on the subject by ESS: http://www.esstech.com/PDF/digital-vs-analog-volume-control.pdf
 
Best
 
Vincent

 
Noted for the reference. Thanks Vincent..
 
 
Cheers,
Gunawan