[jasonl]

 
Quote:

Quote:

Do we know which Sabre chip is inside the uDac-2?

Ive read that it uses the ESS Sabre 9022.

uDAC2 doesn't use ESS Sabre chip

 

[khaos974]

May we know what chip is used or is it secret?
If possible, could we know what the output impedance (headphone out) and at what THD* level it ouputs 80 mW into 16 ohms?
 
*ie, if the stated <0.05% THD is applicable at 2*80 mW.
 
Quote:

uDAC2 doesn't use ESS Sabre chip

 

[WarriorAnt]

Quote:

RE: the 'missing 96/24 bit output on the uDAC-2:
 
I've had the same problem intermittently for several weeks on several Mac's and reported this apparent problem with the USB driver to the NuForce help desk over a week ago.  In the meantime, [waiting for the Help Desk to return from CES] I've exhaustively tried different ways to fix the problem including reinstalling a clean copy of both MacOSX 10.5.8 and 10.6.6 on three separate Mac's to eliminate any possibility of a corrupt USB driver but to no avail - the uDac2 refused to play 96/24 bit data.  
 
As I was moving the uDac2 between Mac's today, I accidentally discovered the source of the problem:  In the AudioMIDI setup utility if BOTH the Input and Output settings are 96/24 bits, then the uDAC2 is silent - however if you set the INPUT to 96/16 bits, and leave the OUTPUT set at 96/24 bits you hear MUSIC!!!
 
It looks to me that the USB receiver chip in the uDAC2 is not handshaking properly with the MacOSX USB driver at the 96/24bit sample rate.  This is obviously something that the NuForce folks need to investigate with Apple
 
scs999
 
 

999,
 
I had the same problem.  I tried the  96/16 but that didn't work for me.  I never got to test the second unit NuForce sent to me because it as defective right out of the box. The on/off light indicator never went off, it was always on and there was severe distortion in the left channel from both the RCA out and the headphone out.   I was pretty annoyed by the second unit arriving as it did and a bit more annoyed by Jason's attitude here in this thread. The whole attitude of hey it's not a $1000 piece of equipment so you have to expect noise or whatever really doesn't sit well with me.   I decided I'm going to update my rig now with about 2K worth of new equipment. None of it is going to NuForce.

 

[scs999]

Quote:

Quote:

RE: the 'missing 96/24 bit output on the uDAC-2:
 
I've had the same problem intermittently for several weeks on several Mac's and reported this apparent problem with the USB driver to the NuForce help desk over a week ago.  In the meantime, [waiting for the Help Desk to return from CES] I've exhaustively tried different ways to fix the problem including reinstalling a clean copy of both MacOSX 10.5.8 and 10.6.6 on three separate Mac's to eliminate any possibility of a corrupt USB driver but to no avail - the uDac2 refused to play 96/24 bit data.  
 
As I was moving the uDac2 between Mac's today, I accidentally discovered the source of the problem:  In the AudioMIDI setup utility if BOTH the Input and Output settings are 96/24 bits, then the uDAC2 is silent - however if you set the INPUT to 96/16 bits, and leave the OUTPUT set at 96/24 bits you hear MUSIC!!!
 
It looks to me that the USB receiver chip in the uDAC2 is not handshaking properly with the MacOSX USB driver at the 96/24bit sample rate.  This is obviously something that the NuForce folks need to investigate with Apple
 
scs999
 
 

999,
 
I had the same problem.  I tried the  96/16 but that didn't work for me.  I never got to test the second unit NuForce sent to me because it as defective right out of the box. The on/off light indicator never went off, it was always on and there was severe distortion in the left channel from both the RCA out and the headphone out.   I was pretty annoyed by the second unit arriving as it did and a bit more annoyed by Jason's attitude here in this thread. The whole attitude of hey it's not a $1000 piece of equipment so you have to expect noise or whatever really doesn't sit well with me.   I decided I'm going to update my rig now with about 2K worth of new equipment. None of it is going to NuForce.

When recording on a Mac, the AudioMIDI setup utility is used to set the sample rate & bit depth and for an audio interface which both records [A to D] and plays back [D to A] like the Apogee Duet or Motu 828, etc.  In this case, you normally have BOTH the input and output set to the same settings and the AudioMIDI utility does this automatically this when you set either the input or output.
 
However the uDac2 is only an OUTPUT device [D to A] and when you use the AudioMIDI utility to set the output rate to 96/24 bits, the INPUT in the software [even though there isn't any on a DAC] defaults to the same 96/24 bits.  For some reason, this causes the uDAC2 to cease passing the analog music signal UNLESS you reset the INPUT side to 96/16 bit.  This makes no sense to me but there appears to be a problem with the USB interface handshake at 96/24 that this 'workaround' fixes.
 
Just to be clear, what works every time [for me] is to set the output to 96/24bits first and then the input to 96/16.

 

[lazpete]

iver read it tdid, but the blogger must have quoted you wrong, Jason.

 

[scs999]

Quote:

 
Quote:

Quote:

Do we know which Sabre chip is inside the uDac-2?

Ive read that it uses the ESS Sabre 9022.

uDAC2 doesn't use ESS Sabre chip

 

 
They must have changed DAC chips in the uDAC2 --> See post #126:
 
http://www.head-fi.org/forum/thread/456945/first-impressions-nuforce-udac-usb-dac-amp-with-line-out-and-s-pdif-out/120#post_6239103
 
Apparently NuForce WAS using an ESS9022 Sabre DAC in the previous model uDAC.
 
The new one sounds great - I wonder which chip they're using now?
 
scs999

 

[jasonl]

 
Quote:

Quote:

 
Quote:

Quote:

Do we know which Sabre chip is inside the uDac-2?

Ive read that it uses the ESS Sabre 9022.

uDAC2 doesn't use ESS Sabre chip

 

 
They must have changed DAC chips in the uDAC2 --> See post #126:
 
http://www.head-fi.org/forum/thread/456945/first-impressions-nuforce-udac-usb-dac-amp-with-line-out-and-s-pdif-out/120#post_6239103
 
Apparently NuForce WAS using an ESS9022 Sabre DAC in the previous model uDAC.
 
The new one sounds great - I wonder which chip they're using now?
 
scs999

Sorry,uDAC-2 still uses ESS 9022, it was the front-end chip that got changed and I got it mixed up.

 

[HeadphoneAddict]

Quote:

 
Quote:

Quote:

 
Quote:

Quote:

Do we know which Sabre chip is inside the uDac-2?

Ive read that it uses the ESS Sabre 9022.

uDAC2 doesn't use ESS Sabre chip

 

 
They must have changed DAC chips in the uDAC2 --> See post #126:
 
http://www.head-fi.org/forum/thread/456945/first-impressions-nuforce-udac-usb-dac-amp-with-line-out-and-s-pdif-out/120#post_6239103
 
Apparently NuForce WAS using an ESS9022 Sabre DAC in the previous model uDAC.
 
The new one sounds great - I wonder which chip they're using now?
 
scs999

Sorry,uDAC-2 still uses ESS 9022, it was the front-end chip that got changed and I got it mixed up.

Awww Maaannnn. I edited my post from August to take out the information about the ESS chip, and now I have to put it back in and I didn't save a copy of the original post.  

 

[jasonl]

 
Quote:

Quote:

Quote:

RE: the 'missing 96/24 bit output on the uDAC-2:
 
I've had the same problem intermittently for several weeks on several Mac's and reported this apparent problem with the USB driver to the NuForce help desk over a week ago.  In the meantime, [waiting for the Help Desk to return from CES] I've exhaustively tried different ways to fix the problem including reinstalling a clean copy of both MacOSX 10.5.8 and 10.6.6 on three separate Mac's to eliminate any possibility of a corrupt USB driver but to no avail - the uDac2 refused to play 96/24 bit data.  
 
As I was moving the uDac2 between Mac's today, I accidentally discovered the source of the problem:  In the AudioMIDI setup utility if BOTH the Input and Output settings are 96/24 bits, then the uDAC2 is silent - however if you set the INPUT to 96/16 bits, and leave the OUTPUT set at 96/24 bits you hear MUSIC!!!
 
It looks to me that the USB receiver chip in the uDAC2 is not handshaking properly with the MacOSX USB driver at the 96/24bit sample rate.  This is obviously something that the NuForce folks need to investigate with Apple
 
scs999
 
 

999,
 
I had the same problem.  I tried the  96/16 but that didn't work for me.  I never got to test the second unit NuForce sent to me because it as defective right out of the box. The on/off light indicator never went off, it was always on and there was severe distortion in the left channel from both the RCA out and the headphone out.   I was pretty annoyed by the second unit arriving as it did and a bit more annoyed by Jason's attitude here in this thread. The whole attitude of hey it's not a $1000 piece of equipment so you have to expect noise or whatever really doesn't sit well with me.   I decided I'm going to update my rig now with about 2K worth of new equipment. None of it is going to NuForce.

When recording on a Mac, the AudioMIDI setup utility is used to set the sample rate & bit depth and for an audio interface which both records [A to D] and plays back [D to A] like the Apogee Duet or Motu 828, etc.  In this case, you normally have BOTH the input and output set to the same settings and the AudioMIDI utility does this automatically this when you set either the input or output.
 
However the uDac2 is only an OUTPUT device [D to A] and when you use the AudioMIDI utility to set the output rate to 96/24 bits, the INPUT in the software [even though there isn't any on a DAC] defaults to the same 96/24 bits.  For some reason, this causes the uDAC2 to cease passing the analog music signal UNLESS you reset the INPUT side to 96/16 bit.  This makes no sense to me but there appears to be a problem with the USB interface handshake at 96/24 that this 'workaround' fixes.
 
Just to be clear, what works every time [for me] is to set the output to 96/24bits first and then the input to 96/16.

Our engineering staff mentioned that the problem could be USB speed can not handle duplex mode: with recording and playback both happening at 24/96.

 

[scs999]

@ JasolL:
 
"Our engineering staff mentioned that the problem could be USB speed can not handle duplex mode: with recording and playback both happening at 24/96."
 
I'm wondering why there is even a configurable entry for INPUT in the Mac's AudioMidi control utility in the first place since this is a DAC ??? 
 
As I indicated in an earlier post, it appears that the Mac and the uDAC2 are improperly handshaking in such a manner that the computer thinks there is an INPUT port on this device and allows this input to be configured.  Any other output only device listed in the AudioMidi utility cannot be configured for input since the Input button is greyed out and hence not selectable.  I'm not sure if this problem is due to the hardware or the software.
 
In any event the ability to configure the 'phantom input' to 96/24 bits causes the DAC to malfunction [no sound passthru.]

 

[bcwang]

Quote:

@ JasolL:
 
"Our engineering staff mentioned that the problem could be USB speed can not handle duplex mode: with recording and playback both happening at 24/96."
 
I'm wondering why there is even a configurable entry for INPUT in the Mac's AudioMidi control utility in the first place since this is a DAC ??? 

It's not just Mac.  On the PC, you see the input pins through asio, so the hardware is probably simply mis-representing it's capabilities.  If the input pin is not disabled in asio, the uDac2 fails to output sound as well.
 

 

[thuantran]

It's not, it's simply there in the USB receiver so your OS picked it up. From the bunch of information I gather about Nuforce USB receiver on the UDAC-2 and the HDP, I say very likely they use the Tenor 7022L chip for them, which has input like that and does not support 88.2KHz sample rate.

 

[scs999]

Quote:

It's not, it's simply there in the USB receiver so your OS picked it up. From the bunch of information I gather about Nuforce USB receiver on the UDAC-2 and the HDP, I say very likely they use the Tenor 7022L chip for them, which has input like that and does not support 88.2KHz sample rate.

That may indeed be the case [the receiver chip presenting it's 'calling card', so to speak, to the OS] but in the HDP [assuming the same USB chip is used] a different display in the AudioMidi utility shows the proper scenario: there is no INPUT to be configured as can be seen in the screen shot in HeadPhoneAddict's excellent review [post #1]:
 
http://www.head-fi.org/forum/thread/469767/review-in-progress-nuforce-hdp-24-96-usb-optical-24-192-coax-dac-preamp-and-headphone-amp
 

 
The above dialog is from the version of the AudioMidi Utility in the previous version of MaxOSX 10.5.x [Leopard] where the utility clearly sees NO input port.
 
 
 However in the latest version, which is part of MacOSX 10.6.x [Snow Leopard], we see the erroneously configurable input port:
 

 
 
There appears to be something about the USB receiver chip's 'handshake' that's fooling the OS into thinking there's an input port on the uDAC2.
 
 

 

[scs999]

Sorry, the second screen shot on my previous post [#658] didn't get thru - one more try:
 
"However in the latest version, which is part of MacOSX 10.6.x [Snow Leopard], we see the erroneously configurable input port:"
 

 

[khaos974]

How's the uDac-2 compared to the Duet, the 828 mk2 or the F66?
And how does it fare as an amp compared to the Asgard.