[upstateguy]

Quote:

Yes, exactly. I waited for your response before further comment.
 
It was the "low jitter" thing that had me thrown off a bit. I think that it is upsampling alone that bothers people, and is considered to be inferior to native/bypassed/non upsampled data. I would tend to think this way because the SRC chip is literally calculating all of the interpolation needed to "fill in the blanks" necessary to make a new/higher sample rate, and doing it on-the-fly so to speak. I can easily see now this may be tolerable going from say 44 to 88, but when going from 44 to 96 there is some work to be done.
 
I think there may be some confusion here, and it may be thought that when the SRC upsamples, that what comes out is something better than before, something totally new and independently retimed. Seems like a lot of listeners have to say that this is not the case. What goes in affects what comes out. PS Audio says that their customers claim that upsampling does not help a good source, but makes it into something inferior to the original native sampled data. I think the Gamma2 sounds pretty good, but I'm not done playing around yet.

I think most of the newer modern DACs upsample, in fact the only DAC that comes to mind that doesn't is the Havana.
 
If that were not the case, DACs like North Star, Benchmark, Lavry 11, etc., wouldn't use it....

It's not PSAudio's customers but PSAudio themselves that make the claim that  running the data through the SRC is sonically inferior to bypassing the SRC when dealing with a high quality low jitter source.
 
Quote:

After a couple weeks with the modded HiFace, I failed to hear a difference.  I decided to mentioned this to the modded hiface designer, just out of curiosity, to see what his response would be.  He said that the DAC's upsampling was making all my sources sound the same.  Since I can't disable my DAC's upsampling, I haven't been able to verify this.  Using another DAC wouldn't help either since if I do hear a difference, I'd be always wondering if it's down to the other DAC's characteristics as opposed to the one I currently have.
 
Anyway, it's this information given to me that made me say that I was of the impression that upsampling DAC's interfere with or even nullify the benefits of the HiFace.
 
However, I have my suspicions about this, especially when I read another post here by JKenny who said that each time he investigated the system for those who aren't hearing a difference with his HiFace, he usually finds a problem and listed one as the user burning CD's with iTunes, as well as, of course, using an upsampling DAC.  It's sounding as though one should always be able to hear a difference???
 
Anyway, here we are now, reading testimonials of differences heard while using upsampling DAC's.
 
I'd love to get to the bottom of this myself.
 
Is the 24/96Kbits/sec Optical Output from an iMac the same as USB out from a NetBook PC?  I'd love to see whether or not this is the case.  I'm suspecting not.

It still is unclear what differences you didn't hear. 
 
Did you notice that the HF plays about 3dbs louder or
 
that it has brighter or treble tilted sound signature, or,
 
did it sound exactly like the optical output from your macbook and you were not able to distinguish between the two?
 
USG

 

[aimlink]

Quote:

It still is unclear what differences you didn't hear. 
 
Did you notice that the HF plays about 3dbs louder or
 
that it has brighter or treble tilted sound signature, or,
 
did it sound exactly like the optical output from your macbook and you were not able to distinguish between the two?
 
USG

To me, it sounded exactly the same.  No difference in volume or treble.
 
I am able to switch back and forth quite quickly too.

 

[upstateguy]

Quote:

To me, it sounded exactly the same.  No difference in volume or treble.
 
I am able to switch back and forth quite quickly too.

That's curious because it has been fairly well documented that the HiFace plays about 3db louder than most other transports.
 
Are you sure you hear no volume differences?  If so, we should look for corroboration on this from some other macbook users?  Perhaps the macbook has a very high digital volume output level?
 
When you switch back and forth, do you have to change an output setting from  something like  "HiFace kernal streaming"  to "usb audio dac" ?
 
Could you post a screen shot of your choices?
 
USG

 

[upstateguy]

@aimlink 
 
I just asked Bubu 1 to join us in this discussion.  He has a macbook also and doesn't hear a volume difference between his optical out and HiFace USB.
 
USG

 

[Sebhelyesfarku]

I hear difference between the MBP optical out and the hiFace, the latter being brighter. Louder? Not sure.

 

[Bubu1]

Is it possible that the hiface is the proper level and other transports are not?  Has anyone compared other transports to optical out?

 

[mmerrill99]

Aimlink,
I emailed you that comment when I was away on holidays - bad communication is a problem when in a rush.  Here's what I said "I suspect why you don't hear much difference between optical out & the Hiface is because of your DAC's upsampling - it will make everything sound the same & prevent the low jitter signal from the Hiface showing it's true colours - can you turn this off?"
 
It should have read "I suspect why you don't hear much difference between optical out & the Hiface is POSSIBLY because of your DAC's upsampling - it COULD make everything sound the same & prevent the low jitter signal from the Hiface showing it's true colours - can you turn this off?"
 
I went on to say, in the next email: "The low jitter output of the Hiface is being negated by the upsampling of the DAC. There is no such thing as a "jitterless digital sound production" - all digital devices have jitter. What upsampling does is apparently change this jitter into other forms of distortion & adds it's own distortion - this is argued about & you will find many different answers to this. Why not try it without the upsampling turned on & tell me if what I say is true?"
 
Sorry, if you have been confused by this - I thought I was being clear but obviously not. I hope that this clarifies my statement.
The DAC (based on the Sabre ES9008) in your Headroom Desktop is doing a better job of upsampling than most other upsamplers (it works differently to other upsamplers) BUT in my experience with this DAC chip family (& others reports also), different inputs to this DAC sound different (even though the ESS marketing dept claim it to be jitter immune). So all I can suggest that if optical in & SPDIF in sounds the same to you & the stock Hiface & modified Hiface sound no different to you then there is something wrong in your system! That is my view.
 
Sorry if it is not what you want to hear! I'm not going to post any further on this - all I wish to say is as above.

 

[Bubu1]

John,
I noticed that adding the attenuator made the differences between the modded Hiface and optical very obvious. I have done this using both my ESS9008 based DAC and another from Headroom that is similar to the one aimlink uses (it uses AD1896 for upsampling to feed the cirrus CS4398 DAC chip). Is it possible that its not the DAC per say, but the connection between the Hiface and the DAC that is the culprit.  The headroom equipment that aimlink and I have use RCA jacks for coax. Perhaps impedance mismatches or reflections are somewhat masking the jitter-reduced signal coming from the modded hiface? Your thoughts are greatly appreciated.  

 

[aimlink]

Quote:

That's curious because it has been fairly well documented that the HiFace plays about 3db louder than most other transports.
 
Are you sure you hear no volume differences?  If so, we should look for corroboration on this from some other macbook users?  Perhaps the macbook has a very high digital volume output level?
 
When you switch back and forth, do you have to change an output setting from  something like  "HiFace kernal streaming"  to "usb audio dac" ?
 
Could you post a screen shot of your choices?
 
USG

I hear no volume difference doesn't necessarily mean that there really isn't one.  Don't forget that this is a subjective issue that we're discussing.  I feel like I'm being held down here and that my assessment is absolute.
 
I switch back and forth in my sound preferences output from 'Digital Out' to 'M2Tech HiFace'.  

 

[mmerrill99]

Aimlink,
Let me make one last suggestion - try ripping a CD to WAV. Do this using something equivalent to Exact Audio Copy on the PC.

 

[aimlink]

Quote:

Aimlink,
Let me make one last suggestion - try ripping a CD to WAV. Do this using something equivalent to Exact Audio Copy on the PC.

Anyone know what would be an equivalent to Exact Audio Copy?
 
I currently use XLD to rip CD's.  I don't know if it's worthy of this exercise.

 

[mmerrill99]

Try it & rip to WAV instead of ALAC & let us know the results.

 

[aimlink]

Quote:

Try it & rip to WAV instead of ALAC & let us know the results.

No difference either.....
 
Did we genuinely expect otherwise??

 

[mmerrill99]

Yes, I expected a difference & hoped it was your problem!
What SPDIF cable are you using?
You don't have anything between the Hiface & the Headroom Desktop, do you?
Anything else that might be of note?

 

[aimlink]

Quote:

Yes, I expected a difference & hoped it was your problem!
What SPDIF cable are you using?
You don't have anything between the Hiface & the Headroom Desktop, do you?
Anything else that might be of note?

Would you explain why you expected to hear a difference?
 
My SPDIF cable is a Esoteric ED15-0.5M
 
I have nothing between the HiFace and the HeadRoom Desktop.
 
USB cable is USB 3.0 Male to Female Cable 0.5m 5ft