Frequently asked questions
1. Do S/PDIF and I2S work simultaneously?
2. What does a galvanic isolator do?
4. Is there an effect of the galvanic isolation since it brings jitter?
5. I can playback sample rates up to 384kHz, but no DSD?
6. Is I2SoverUSB will be working with my DAC?
Yes, they work simultaneously up to 192kHz, because S/PDIF is specified up to 192kHz. For higher sampling rates only I2S is working. 2. What does a galvanic isolator do?
The aim of the galvanic isolation is to eliminate common noise originated by the computer and to avoid ground loops. 3. What does a reclock do?
The reclock significantly reduces the jitter caused by the galvanic isolator. For example IL715 has 100ps typical pulse jitter.
If connection lines are longer than 15cm, there is no problem to have second reclock just before the DAC.
4. Is there any sense of the galvanic isolation since it brings jitter?
The galvanic isolation should be considered related to the reclock. Numerous listening sessions held with different listeners clearly show that presence of galvanic isolation and reclock after that makes sense.
5. I can playback sample rates up to 384kHz, but no DSD?
Please check the foobar_ASIO_setup.pdf If I2SoverUSB detects DSD data, pin8 must be 3.3V. 6. Is I2SoverUSB will be working with my DAC?
If your DAC meets any of the standards which I2SoverUSB supports – yes. 7. Should I use an external power supply?
To extract maximum benefit from asynchronous audio transfer, we recommend to use an external low noise power supply especially for oscillators and reclock. 8. Are 32 bit depth for real?
Yes, they are real. If source can playback them and the record is with 32 bit resolution. One can check that with a digital oscilloscope (persistence display mode). Connect the first probe to LRCK line and synchronize with this signal, connect second probe to DATA line. To filter the most significant bit, reduce the gain of the signal by 30-40 dB and you should see the following pictures:
