[EliasGwinn]

If it is working with 192 kHz going into the Toslink, then you have the 192 kHz update.

Best,
Elias

 

[music_man]

thank you mr gwinn.

music_man

 

[techenvy]

has anyone compared the benchmark dac 1 usb to the hiface usb?
 
thanks

 

[G-U-E-S-T]

Quote:

has anyone compared the benchmark dac 1 usb to the hiface usb?
 
thanks

Guess not, techenvy
 

 

[Bmac]

 
Hi Elias,
 
I was reading through John Siau's interviews in the Benchmark feedback newsletter and found the answer to the following question very interesting:
 
"EAN: The audio world is often filled with tweaks and gizmos that claim to improve the sound of audio; many of those improvements don’t show up in test measurements? Are there some audible differences that just can’t be measured? Or do you believe that the claimed improvements are not really there?
 
Siau: I firmly believe that we can measure many defects that are not audible. I am sure that there are a few audible defects that we are not detecting with our test equipment, but I believe these are rare. It may surprise you that I have measured significant differences in speaker cables. People have claimed audible differences in cables, and it turns out that differences can be measured! BTW, zip-cord isn’t half bad! But maybe this is a topic for another day."
 
I was just wondering if you could elaborate on how and what differences John was able to measure in different cables and the subjective impressions of the measured differences if any. It would be great to hear what an independent third party like yourselves was able to find.
 
Thanks.
is a topic for another day.EAN: The audio world is often filled with tweaks and gizmos that claim to
improve the sound of audio; many of those improvements don’t show up in test
measurements? Are there some audible differences that just can’t be measured?
Or do you believe that the claimed improvements are not really there?
Siau: I firmly believe that we can measure many defects that are not audible. I am sure
that there are a few audible defects that we are not detecting with our test equipment,
but I believe these are rare. It may surprise you that I have measured significant
differences in speaker cables. People have claimed audible differences in cables, and it
turns out that differences can be measured! BTW, zip-cord isn’t half bad! But maybe this
is a topic for another day.EAN: The audio world is often filled with tweaks and gizmos that claim to
improve the sound of audio; many of those improvements don’t show up in test
measurements? Are there some audible differences that just can’t be measured?
Or do you believe that the claimed improvements are not really there?
Siau: I firmly believe that we can measure many defects that are not audible. I am sure
that there are a few audible defects that we are not detecting with our test equipment,
but I believe these are rare. It may surprise you that I have measured significant
differences in speaker cables. People have claimed audible differences in cables, and it
turns out that differences can be measured! BTW, zip-cord isn’t half bad! But maybe this
is a topic for another day.EAN: The audio world is often filled with tweaks and gizmos that claim to
improve the sound of audio; many of those improvements don’t show up in test
measurements? Are there some audible differences that just can’t be measured?
Or do you believe that the claimed improvements are not really there?
Siau: I firmly believe that we can measure many defects that are not audible. I am sure
that there are a few audible defects that we are not detecting with our test equipment,
but I believe these are rare. It may surprise you that I have measured significant
differences in speaker cables. People have claimed audible differences in cables, and it
turns out that differences can be measured! BTW, zip-cord isn’t half bad! But maybe this
is a topic for another day.

 

[Roseval]

http://www.hydrogenaudio.org/forums/index.php?showtopic=75627&st=25

 

[Bmac]

Thanks for the link!

 

[EliasGwinn]

Hi Bmac,
 
John did a test w/ a variety of different 'types' of cables driving passive speakers. 
 
To give a brief summary, the tests proved that the major defining characteristic of a speaker cable is its inductance.  Inductance causes much more sonic variation then 'skin effect', the commonly quoted culprit.  Especially with long speaker cables (> 20 ft), very audible changes in frequency response begin to occur because of the LCR filter created w/ the speaker. 
 
In other words, a speaker has a complex impedance that varies radically w/ frequency and coil temperature.  Passive crossovers create even more radical variations.  The higher the inductance of the cable, the more the frequency response of the system will be affected by these variations.
 
The output impedance of the amplifier will further exaggerate the variations.  For this reason, a low output impedance will give the most linear results.
 
Best,
Elias
 
Quote:

Originally Posted by Bmac /img/forum/go_quote.gif
 
I was just wondering if you could elaborate on how and what differences John was able to measure in different cables and the subjective impressions of the measured differences if any. It would be great to hear what an independent third party like yourselves was able to find.

 

[Bmac]

Thanks Elias!

 

[axellone]

 
But you never tried to use an AKG K1000 with dac1?
It' was a wonderful surprise!

 

[ANagorny]

Hi Elias!
 
First of all, thank you so much for the great products and for your patience in answering hundreds of questions here!
 
I recently purchased a DAC1 HDR, and have a bit of an issue with the channel imbalance - it seems to be shifted to the left channel a bit. As you suggested earlier in this thread, I measured the AC voltage between the 2 and 3 pin of the XLR outputs while playing 60Hz sine signal.
 
The results I have got are below:

 
Could you please let me know if this is within the specification, and if there is any way for me to correct this imbalance (maybe by some internal calibration controls inside the DAC1)?
 
Really appreciate your help!!!
 
Regards,
Anatoliy

 

[EliasGwinn]

Hi ANagorny,
 
That looks about right.  You will want to keep the volume control at or above the 11 o'clock position. 
 
Let me know if I can answer any more questions for you.
 
All the best,
-Elias

 

[ANagorny]

Thanks for answering so promptly, Elias!
 
I can still hear the imbalance though - and the problem goes away when I switch to Calibrated setting. Is there any way to individually adjust channel balance in the DAC1 HDR and reduce the level of left channel?
 
If I am not mistaken, I remember you mentioning somehting about L/R calibration controls in DAC1 USB...
 
Thanks again!

 

[EliasGwinn]

There is a L/R calibration pot.  It is factory calibrated to achieve a balance within 0.01 dB when the volume knob is near 2 o'clock.
 
Where do you usually have the volume knob while listening?
 
Thanks,
Elias

 

[ANagorny]

My listening position is around 12 o'clock, and 2-3 o'clock when I really crank it up
 
I have actually got some comments from John Siau on the Benchmark board, he kindly recalculated my voltage measurements into dB:
 

[size=small]Pot Rotation[/size]	[size=small]L (Volt)[/size]	[size=small]R (Volt)[/size]	[size=small]Imbalance (dB)[/size]
[size=small]9 o'clock[/size]	[size=small]0.024[/size]	[size=small]0.021[/size]	[size=small]1.160[/size]
[size=small]10 o'clock[/size]	[size=small]0.108[/size]	[size=small]0.1[/size]	[size=small]0.668[/size]
[size=small]11 o'clock[/size]	[size=small]0.272[/size]	[size=small]0.26[/size]	[size=small]0.392[/size]
[size=small]12 o'clock[/size]	[size=small]0.497[/size]	[size=small]0.488[/size]	[size=small]0.159[/size]
[size=small]13 o'clock[/size]	[size=small]0.825[/size]	[size=small]0.817[/size]	[size=small]0.085[/size]
[size=small]14 o'clock[/size]	[size=small]1.303[/size]	[size=small]1.289[/size]	[size=small]0.094[/size]
[size=small]15 o'clock[/size]	[size=small]1.735[/size]	[size=small]1.71[/size]	[size=small]0.126[/size]
[size=small]Maximum[/size]	[size=small]1.899[/size]	[size=small]1.871[/size]	[size=small]0.129[/size]
[size=small]Calibrated[/size]	[size=small]1.271[/size]	[size=small]1.272[/size]	[size=small]-0.007[/size]

 
I am quoting his reply as well, I think it will be useful to the community here:
 
Quote:

Balance is adjustable, but is factory preset to high accuracy. It is unlikely that the setting has been lost, so please check the following before adjusting the balance control:
 
1)      Make sure that all 4 XLR output attenuator jumpers are set identically. This is this most common cause of an imbalance. Factory preset is 20 dB.
2)      If you are using the XLR outputs, insure that a normal listening level is achieved near a 12 o’clock volume control position. If normal listening levels are not obtained near 12 o’clock, change the XLR output attenuator settings. XLR outputs can be adjusted over a 30dB range to optimize the gain-staging between the DAC1 and your power amplifier.
a.       If normal volume is achieved well below 12 o’clock, increase the attenuation (i.e. change from 20 dB to 30 dB).
b.      If normal volume is achieved well above 12 o’clock, decrease the attenuation (i.e. change from 20 dB to 10dB or 0 dB).
3)      If you still have an imbalance, reverse the L and R XLR connectors. If the imbalance does not change, the amplifier balance is mismatched. If the imbalance move to the opposite speaker the DAC1 may need adjustment.
 
To adjust the DAC1 HDR L/R balance, we recommend using an accurate calibration recording and a meter:
1)      Set the volume control at 12-o’clock.  For maximum accuracy, press "MUTE" on the remote, then press "On" on the remote to allow the motor to drive the pot clockwise to 12 o'clock.
2)      XLR outputs should be measured between pins 2 and 3 of the XLR outputs.
3)      If the L and R outputs measure differently, adjust the L/R BAL pot. This is the 9-turn pot located directly behind the right-hand headphone jack.
4)      Output should now be well balanced when the volume control is above 9-oclock.
5)      Below 9-oclock some volume-control imbalance is normal as the volume control goes approaches full off.
6)      Caution: Do not attempt to set the balance control with the volume control at a fully clockwise position (errors will be large). Set balance only when the volume control is at 12-o’clock.

 
If the factory-set precision is 0.01dB, then my unit seems to be a bit off... I am not exactly clear about how the L/R pot actually works and how much it changes the balance, so would be great to hear some comments about it. Thanks!