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Gungnir MultiBit technical measurements

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atomicbob:
20150926 UPDATE - last section added comparing 1 KHz -90 dBFS Balanced vs. Single Ended between Optical, SPDIF and USB inputs.

Look carefully at the jitter graphs. Gungnir MB jitter is impressively low.  Balanced output has an exceptionally low noise floor. Single ended jitter measurement is a little higher in residual noise floor as expected.

Channel matching is excellent.  Frequency response and square wave response left and right channels are so well matched as to overlay one another.

The 1 KHz -90 dBFS sine Single Ended measurement appears a little noisier than I would have expected and would still entertain the notion of a setup problem, though many corrective actions were attempted.

Balanced XLR measurements were at approximately 1 hr of power on time.
Single Ended RCA measurements were at approximately 3 hrs of power on time.
Balanced XLR through Radial Twin ISO (Jensen transformers) for conversion to single ended output measurements were at approximately 4 hrs of power on time.

The Gungnir MB data presented were collected as follows:
 
1.  PrismSound dScope III, picoscope 5243B
2.  DAC balanced output XLR, unbalanced output RCA
3.  100 Kohm load used for measurements
4.  44 KHz  sample rate, 24 bit depth
5.  USB input – Audioquest Forest
6.  Balanced cable Canare L-4E6S with Neutrik XLR
7.  Unbalance cable DH Labs Silver Sonic Air Matrix RCA
8.  Vaunix Lab Brick USB hub

Balanced XLR output measurements part A

Frequency Response



Frequency Response (y-axis zoom)



Dynamic Range



THD+N



IMD



Crosstalk



Inferred Jitter



Inferred Jitter (x axis zoom)

atomicbob:
Balanced XLR output measurements part B

1kHz @ -90dBFS



20 Hz square wave 0dBFS 6Vpp 10ms



20 Hz square wave 0dBFS 6Vpp 500us



1 kHz gain linearity



Imaging

atomicbob:
Single Ended RCA output measurements part A

Frequency Response



Frequency Response (y-axis zoom)



Dynamic Range



THD+N



IMD



Crosstalk



Inferred Jitter



Inferred Jitter (x axis zoom)

atomicbob:
Single Ended RCA output measurements part B

1kHz @ -90dBFS   The noise has quieted somewhat after 27 hrs of power on time. See reply #6.



20 Hz square wave 0dBFS 6Vpp 10ms



20 Hz square wave 0dBFS 6Vpp 500us



1 kHz gain linearity



Imaging

atomicbob:
Balanced XLR output through Radial Twin ISO (Jensen transformers) for single ended conversion measurements part A

Frequency Response



Frequency Response (y-axis zoom)



Dynamic Range



THD+N



IMD



Crosstalk



Inferred Jitter



Inferred Jitter (x axis zoom)

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