I took a pair of my old early 90's DACs from the storage and fed bunch of measurements through both. Source for both was MuFi V-Link192 at 44.1k output. As result of doing this at midnight I forgot to change the output to 16-bit, so you may see some truncation quantization effects too... Both of the DACs claim 18-bit resolution.

 

Participants:

 

1) Crystal Semiconductor CS4328 64x oversampling 1-bit DAC chip with 8x interpolation and fifth-order modulator. IOW, so it's pretty much a "DSD DAC". S/PDIF receiver is Yamaha YM3623B.

 

As numbers:

THD: 0.003%

IMD: 0.004%

 

1 kHz tone:

 

 

 

Digital silence:

 

 

 

19 + 20 kHz IMD test tone:

 

 

 

Frequency response:

 

 

 

0 - 20 kHz sweep, wide band:

 

 

 

16-bit J-test:

 

 

 

Impulse response (note vertical scale):

 

 

 

 

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2) Burr-Brown DF1700P 8x oversampling digital filter configured for 18-bit output and PCM1700P 18-bit R2R ladder DAC. S/PDIF receiver is Crystal Semiconductor CS8412.

 

As numbers:

THD: 0.007%

IMD: 0.024%

 

1 kHz tone:

 

 

 

Digital silence:

 

 

 

 

19 + 20 kHz IMD test tone:

 

 

 

 

Frequency response:

 

 

 

0 - 20 kHz sweep, wide band:

 

 

 

16-bit J-test:

 

 

 

Impulse response (note vertical scale):

 

 

 

 

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Conclusions:

- 2.8 MHz sampling rate of CS4328 is quite apparent from the wideband sweep spectrum.

- DF1700 + PCM1700 has higher distortion.

- Jitter figures are similar and anyway depend on the S/PDIF receiver chips.

- Impulse responses are very similar, by eye almost the same.

- DF1700 + PCM1700 is more silent when playing silence.

- Amount of noise-shaping noise from the 1-bit 2.8 MHz CS4328 is minimal.