DACLadder
Headphoneus Supremus
- Joined
- Feb 16, 2013
- Posts
- 2,280
- Likes
- 2,111
@Wynnytsky Balanced lines (differential) reduce common mode noise or employ "common mode rejection" per your diagram. The induced noise is the same phase (common) on both lines of the pair but when summed in the receive the net result of noise is near zero. The audio signal, with one side inverted, is not common and gets summed in the receiver. Audio - (- Audio) = 2 x Audio. Noise - Noise = 0. The best example of common mode noise rejection is a balanced microphone with 100 ft. of cable. The noise on the line is probably larger than the actual microphone signal but gets 'rejected' at the balanced receiver.
With single phase everything gets amplified. Other examples in the same way balanced DACs and amplifiers reject common power suppy noise and induced noises.
@Articnoise I still use the homemade I2S boards designed back in 2014. All three DACs. Kingwa was slow to adopt LVDS I2S (I2s over HDMI hardware) as he was deathly afraid of being sued by HDMI.org. No worries as all you have to state is "this interface is not HDMI protocol compatible".. HDMI.org still makes money off of cable and connector royalties.
LVDS is superior to TTL I2S as far as preserving jitter and signal quality. This was especially true when I2S Mclk was used to recover I2S audio. With asynchronous firmware Mclk is no longer used but I2S is still king on my DACs. So "garbage in, garbage out" rule still applies. But with each year and newer firmware/ technology there is less and less variation between inputs.
With single phase everything gets amplified. Other examples in the same way balanced DACs and amplifiers reject common power suppy noise and induced noises.
@Articnoise I still use the homemade I2S boards designed back in 2014. All three DACs. Kingwa was slow to adopt LVDS I2S (I2s over HDMI hardware) as he was deathly afraid of being sued by HDMI.org. No worries as all you have to state is "this interface is not HDMI protocol compatible".. HDMI.org still makes money off of cable and connector royalties.
LVDS is superior to TTL I2S as far as preserving jitter and signal quality. This was especially true when I2S Mclk was used to recover I2S audio. With asynchronous firmware Mclk is no longer used but I2S is still king on my DACs. So "garbage in, garbage out" rule still applies. But with each year and newer firmware/ technology there is less and less variation between inputs.
Last edited: