misureaudio
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Some spectral estimates are presented here, about three Bricasti DACs.
Two M3 DACs are examined first, an early (March 2019) non Mdx sample and a very recent (presumably first half 2022) M3h Mdx.
A M1SE DAC, with last-revision (May 2019) non Mdx digital board is further examined.
Tests are made with a National Instruments PXI-1033 having two PXI-446x Dynamic Signal Analyzers. Those are connected to a host PC, which is equipped with LabVIEW software and custom made acquisition and analysis tools. A SFDR (Spurious Free Dynamic Range) of 118dB is declared for the PXI-446x series DSAs.
The DAC under test is used as generator, driven by ASIO USB.
Foobar2000 is the audio player software. Appropriate plugins are installed to allow DSD playback in DoP mode when required, via ASIO USB.
The ASIO driver is the TUSB 1.6. (A newer one exists but it showed a problematic behaviour, so I decided to stick to the former version).
Test files containing the multitone stimulus signal are generated by Matlab and saved in flac format when PCM.
Multitone signal is calculated with an attenuation coefficient of -0.25 dB with respect to the maximum allowable digital value. (What you see in the spectral estimates reports the level of the single tone components, with obvious attenuation, while the signal, in the time domain, reaches peak values near the allowable maximum).
Alternatively the same multitone signal is converted in DSD128 using the TEAC editor, to test the DSD capabilities of the DACs.
Tests are made with a 4Ms-long acquisition buffer, allowing 20 passes to calculate a RMS average. Entire test with multitone stimulus, sampled at 192kHz-24bit, lasts about 7min 40secs.
4-th order Blackman-Harris windows are used in calculating the spectral estimates.
Here the report about Bricasti M3 non Mdx.
Firmware version 1.03. S/N 1012
Bricasti M3 non Mdx: PCM decoding, linear reconstruction filter:
Bricasti M3 non Mdx: PCM decoding, minimum phase reconstruction filter, Sync Fine mode:
Bricasti M3 non Mdx: PCM decoding, minimum phase reconstruction filter, Sync Wide mode:
Bricasti M3 non Mdx: DSD decoding, DSD2PCM conversion from DoP DSD128 signal:
Bricasti M3 non Mdx: DSD decoding, NDSD Native DSD mode from DoP DSD128 signal:
Bricasti M3 non Mdx, 1kHz, 0dBFs signal, 4 passes RMS average, Sync Fine mode:
Bricasti M3 non Mdx, 1kHz, 0dBFs signal, 4 passes RMS average, Sync Wide mode:
We report here, instead, about the M3h Mdx.
Firmware version: 1.08. (S/N not reported: borrowed sample, serial not printed on the device)
Bricasti M3h Mdx: PCM decoding, minimum phase reconstruction filter:
Bricasti M3h Mdx: DSD decoding, DSD2PCM conversion from DoP DSD128 signal:
Bricasti M3h Mdx: DSD decoding, NDSD native conversion from DoP DSD128 signal:
Bricasti M3h Mdx: PCM decoding, 1kHz, 0dBFs signal:
(In the new Mdx configuration, there no more switchable options (Sync Fine/Sync Wide)
Bricasti M3h Mdx, same multitone signal at a level of -90dBFs:
Two M3 DACs are examined first, an early (March 2019) non Mdx sample and a very recent (presumably first half 2022) M3h Mdx.
A M1SE DAC, with last-revision (May 2019) non Mdx digital board is further examined.
Tests are made with a National Instruments PXI-1033 having two PXI-446x Dynamic Signal Analyzers. Those are connected to a host PC, which is equipped with LabVIEW software and custom made acquisition and analysis tools. A SFDR (Spurious Free Dynamic Range) of 118dB is declared for the PXI-446x series DSAs.
The DAC under test is used as generator, driven by ASIO USB.
Foobar2000 is the audio player software. Appropriate plugins are installed to allow DSD playback in DoP mode when required, via ASIO USB.
The ASIO driver is the TUSB 1.6. (A newer one exists but it showed a problematic behaviour, so I decided to stick to the former version).
Test files containing the multitone stimulus signal are generated by Matlab and saved in flac format when PCM.
Multitone signal is calculated with an attenuation coefficient of -0.25 dB with respect to the maximum allowable digital value. (What you see in the spectral estimates reports the level of the single tone components, with obvious attenuation, while the signal, in the time domain, reaches peak values near the allowable maximum).
Alternatively the same multitone signal is converted in DSD128 using the TEAC editor, to test the DSD capabilities of the DACs.
Tests are made with a 4Ms-long acquisition buffer, allowing 20 passes to calculate a RMS average. Entire test with multitone stimulus, sampled at 192kHz-24bit, lasts about 7min 40secs.
4-th order Blackman-Harris windows are used in calculating the spectral estimates.
Here the report about Bricasti M3 non Mdx.
Firmware version 1.03. S/N 1012
Bricasti M3 non Mdx: PCM decoding, linear reconstruction filter:
Bricasti M3 non Mdx: PCM decoding, minimum phase reconstruction filter, Sync Fine mode:
Bricasti M3 non Mdx: PCM decoding, minimum phase reconstruction filter, Sync Wide mode:
Bricasti M3 non Mdx: DSD decoding, DSD2PCM conversion from DoP DSD128 signal:
Bricasti M3 non Mdx: DSD decoding, NDSD Native DSD mode from DoP DSD128 signal:
Bricasti M3 non Mdx, 1kHz, 0dBFs signal, 4 passes RMS average, Sync Fine mode:
Bricasti M3 non Mdx, 1kHz, 0dBFs signal, 4 passes RMS average, Sync Wide mode:
We report here, instead, about the M3h Mdx.
Firmware version: 1.08. (S/N not reported: borrowed sample, serial not printed on the device)
Bricasti M3h Mdx: PCM decoding, minimum phase reconstruction filter:
Bricasti M3h Mdx: DSD decoding, DSD2PCM conversion from DoP DSD128 signal:
Bricasti M3h Mdx: DSD decoding, NDSD native conversion from DoP DSD128 signal:
Bricasti M3h Mdx: PCM decoding, 1kHz, 0dBFs signal:
(In the new Mdx configuration, there no more switchable options (Sync Fine/Sync Wide)
Bricasti M3h Mdx, same multitone signal at a level of -90dBFs:
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