Marcel, you are welcome.
Right observation since I wrote that I would use sigma delta DACs for cooking a pizza.
When I was in Auburn last year Mark and Jam pressed me hard to build a DSD DAC.
Even though we weren’t very convinced, especially Roberto, we finally decided to give it a try.
In the end I have to change my mind, after the last adjustments the DSD DAC sounds very good.
Roberto still prefers the PCM DAC, I prefer both, so much so that in the Sonic Empire version we are working on we will implement both with some improvements.
IMHO the DSD DAC it’s more detailed and the soundstage is better, while the PCM DAC has better midrange.
Depending on the music I listen to I prefer one or the other.
We had a listening session just last tuensday, the differences between the two DACs are getting smaller and smaller.
Both DAC were driven by the FIFO Lite with DRIXO oscillators.
For the DAC Lite we have used a Zanden filter follewed by a diamond buffer.
The DSD DAC was configured as folow:
– JLSounds I2SoverUSB
– Simple DSD converter to DSD256 (FPGA project posted on diyaudio)
– FIFO Lite working in RTZ mode
– 5/6 MHz oscillators followed by a pair of doublers for each sample rate family to reach 22/24 MHz
– differential to single ended buffer
We also have tried single ended output from the DAC, decoupled with 33uF Mundorf EVO oil. Maybe it sounds still better, but the output voltage was too low (divided by 4, RTZ and single ended).
There was a clearly audible difference when we have used the 22/24 MHz DRIXO directly. With 5/6 MHz DRIXO and doublers the DSD DAC sounds better. Which means that subharmonics don’t matter much.
Obviously the FFT wouldn’t detect any difference, but that’s another topic.
- This reply was modified 8 months ago by The Well Audio.