DACs

Bryston BDA-2 DAC

ARTICLE INDEX

On the Bench

All distortion measurements were within an 80 kHz bandwidth, and I used the XLR balanced outputs of the BDA-2 DAC. All digital test signals were at -5 dB unless otherwise stated.

At 16/44.1, 1 kHz sine wave, and 0 dB, the output was 3.9 volts, which is the maximum voltage the unit can produce. Distortion was 0.002%.

Bryston BDA-2 DAC

 

With the same signal at -5 dB, which is a more realistic level, the output was 2.2 volts, and distortion was 0.004%. If you compare these results with the BDA-1, you can see that the BDA-2 has a small, but measurable improvement. (Note however, that the "transport" for the BDA-1 tests was the BDP-1 music server.)

Bryston BDA-2 DAC

 

Using 19 kHz and 20 kHz sine waves, at 16/44.1, there were only two small side bands near the fundamentals, and there was no visible B-A peak at 1 kHz.

Bryston BDA-2 DAC

 

IM distortion came in at 0.005%, using a 16/44.1 test signal.

http://www.hometheaterhifi.com/media-servers/media-servers-reviews/bryston-bdp-1-music-server-and-bda-1-dac/page-4-the-bdp-1-and-bda-1-on-the-bench.html

 

The measured frequency response for 16/44.1 was 10 Hz - 19 kHz, ± 0.1 dB, with a 0.8 dB roll-off between 19 kHz and 20 kHz.

Bryston BDA-2 DAC

 

The results for 24/96 and 24/192 were the same, so I will illustrate just the 24/192 graphs.

At 1 kHz, THD+N was 0.009%. This is truly excellent!

Bryston BDA-2 DAC

 

With 19 kHz and 20 kHz, there were no visible side bands, and there was a visible B-A peak 104 dB below the fundamentals.

Bryston BDA-2 DAC

 

IMD at 24/192 was 0.002%.

Bryston BDA-2 DAC

 

The measured frequency response at 24/192 was flat to about 25 kHz, followed by a decline of 7 dB out to 90 kHz.

Bryston BDA-2 DAC

 

Now, here is a 1 kHz sine wave digital signal played from my computer connected to the BDA-2 through the USB input. The distortion is the same as with the coax input, but notice the improved noise floor, which is significantly lower than with the coax input.

Bryston BDA-2 DAC

 

I also measured the jitter reduction of the DAC by inducing a specified amount of jitter in a 10 kHz sine wave and measuring the jitter in the signal from the S/PDIF output jack on the BDA-2. With the signal jittered at 531 picoseconds, the output had a measured jitter of 448 picoseconds, which is a 16% reduction. In other words, the DAC could reduce the jitter with its asynchronous design, by 16%. This is a new measurement for consumer A/V reviews, so we have to wait and see how this compares with other DACs tested down the road.