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Quick measurements: Holo Audio Spring DAC v1 Level 1

pkane

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This DAC has been measured before, but I think my results are sufficiently different to warrant yet another data point. This is stock Holo Spring v1, Level 1, R2R DAC. Measured using ADI-2 Pro FS ADC and REW.

Some of the highlights:
  • Lower THD+N -108.1dBFS @1KHz
  • Lower jitter
  • Cleaner multi-tone
1KHz, -2dBFS, 44.1KHz, balanced output @ 3.926V:
SINAD-OS-Mode.png


Distortions vs. Frequency:
THDN+Freq.png


Distortions vs. Level:
THDN+Level-using-ADI2-Pro.png


Jitter J-Test:
JTEST-using-ADI2-Pro.png


Multitone signal:
Multitone-using-ADI2-Pro.png
 

Angsty

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This DAC has been measured before, but I think my results are sufficiently different to warrant yet another data point. This is stock Holo Spring v1, Level 1, R2R DAC. Measured using ADI-2 Pro FS ADC and REW.

Some of the highlights:
  • Lower THD+N -108.1dBFS @1KHz
  • Lower jitter
  • Cleaner multi-tone
1KHz, -2dBFS, 44.1KHz, balanced output @ 3.926V:
View attachment 131256

Distortions vs. Frequency:
View attachment 131257

Distortions vs. Level:
View attachment 131249

Jitter J-Test:
View attachment 131250

Multitone signal:
View attachment 131251
I can’t recall seeing a nicer multi-tone.
 
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pkane

pkane

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A discussion of DSD vs PCM came up in another thread with Holo Audio R2R DACs being mentioned. Measurements using a mic and speakers showing large frequency differences in the audible spectrum were shared. I decided to record the output of Holo Spring v1 being fed by DSD256 and then by PCM384 to compare the two using DeltaWave. Recording was done by ADI-2 Pro FS at 176.4k, with the same musical recording that's used by Gearspace Diffmaker thread.

Here's the result:

1629510693417.png


Spectrum of the null (difference) file:
1629510855318.png


Phase difference:
1629510882916.png


And now, the same null (difference) waveform adjusted for audibility using some perceptual metrics in PK Metric plot:

1629510982808.png


Needless to say, there's very little audibly different between these two recordings using DSD256 and PCM384 when captured at the output of the DAC.

As a calibration run, here's Holo Spring playing 1kHz DSD256 tone, recorded by ADI-2pro at 176.4k:

Holo-DSD256-OS-174.png


And here's the same with PCM384:

Holo-384-OS-174.png
 
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Blumlein 88

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If he doesn't, please share your guess. Transients ? Do you seriously believe that recording the output of the DAC is an accurate representation of what reaches our ears? I know my repeated comps yield consistent results, I have no doubt your test is earnest. It simply is not relevant to show how the same music, made of impulses, excite differently certain frequencies of the room and thus our ears , whether it's PCM or SDM processed : thank you for showing it doesn't come from some DSP trick that would modify the frequency response. It is also very possible and respectable that you're not sensitive to time domain the way I am
I'd say you don't quite understand how this test works. How do you think the time domain isn't addressed here?
 
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pma

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1KHz, -2dBFS, 44.1KHz, balanced output @ 3.926V:

Is there any dither used in the generated test signal? Do you have a spectrum analysis of the test tone itself?
 
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pkane

pkane

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If he doesn't, please share your guess. Transients ? Do you seriously believe that recording the output of the DAC is an accurate representation of what reaches our ears? I know my repeated comps yield consistent results, I have no doubt your test is earnest. It simply is not relevant to show how the same music, made of impulses, excite differently certain frequencies of the room and thus our ears , whether it's PCM or SDM processed : thank you for showing it doesn't come from some DSP trick that would modify the frequency response. It is also very possible and respectable that you're not sensitive to time domain the way I am

What reaches our ears first goes through the DAC, which is where the difference was measured. Consistent results don't indicate correct results. As I pointed out before, you are conflating too many things and then making a conclusion about the source format that is not justified by your measurements.
 

Le Concombre

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What reaches our ears first goes through the DAC, which is where the difference was measured. Consistent results don't indicate correct results. As I pointed out before, you are conflating too many things and then making a conclusion about the source format that is not justified by your measurements.
As I pointed out before the feed and thus the path inside the Spring is the only variable.
 

Le Concombre

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I'd say you don't quite understand how this test works. How do you think the time domain isn't addressed here?
there is no measurement of how transients excite the room differently whether the feed and thus the path inside the DAC is PCM or DSD. If you believe that measuring the phase is a correct measurement of transients and represent correctly how the room and thus our ears react to music impulses, please explain
 

Le Concombre

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Are you saying that when you record amplitude in dB as a function of frequency for the whole length of a track it shows transients ? or are you saying that transient should have appeared as phase shifts ? Another non sense or I'm missing something pertaining to transients in anything you posted ?
 
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