Beolab
Member of the Trade (Reseller)
- Joined
- Apr 16, 2015
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Its like an old great red wine, it matures you more you taste it..
Optical will sound the best. Don't worry about source jitter at all, Dave eliminates it.
Rob
For both tt and Dave, usb is best, closely followed by optical, then last is coax.
Normally dacs are sensitive to source jitter, but my dacs are not, due to the DPLL which eliminates incoming jitter, buffers the data and creates a local clock sychronisation.
So you are just left with benefits of optical which is galvanic isolation, which reduces noise floor modulation thus making it sound smoother and darker. With usb we have galvanic isolation too, but the clock is allready local as timing for usb comes from the dac.
I am currently designing a ADC converter, that will match Dave's performance, and solve a number of issues that plague conventional ADC's - notably huge noise floor modulation, poor anti-aliasing filters, and poor noise shaper performance.
I know from the work with Dave that the perception of depth needs noise shapers of astounding accuracy; indeed, Dave ended up with 350 dB performance noise shapers, in order to ensure that small signals are resolved with zero error - from listening tests, this is needed to ensure the brain can perceive depth correctly.
Now I have designed a ADC noise shaper that exceeds 350 dB performance (note these numbers are digital domain performance only, so it is an idealised noise shaper - I am only looking at the THD and noise of the noise shaper only). To test the noise shaper I can run Verilog simulations, capture the data, then do an FFT on the data, and then check the results. Before I did that, I thought it would be a good idea to run a similar simulation with Dave's noise shaper. In this case, I am trying to evaluate whether it can accurately encode very small signals, so I am using a -301 dB sine wave at 6 kHz. If it can resolve a signal at -301 dB, then we can safely say that small signals are accurately encoded, at least in the digital domain.
So here are the results:
So this is the digital domain performance of the Dave noise shaper, and frequency is from DC to 100kHz (0.1 MHz).
The 6 kHz signal is perfectly reconstituted at -301 dB. You can see a flat line at -340 dB, but this is just a FFT issue. The real noise floor at 15 kHz is at -380 dB, which is about 100 trillion times lower noise than conventional high performance noise shapers. Note also the noise at 100 kHz is at -200 dB - that is extraordinary low for a noise shaper, and shows why I need to do little filtering on the analogue side.
-301 db is better than 50 bits accuracy.
Now to write the code for the ADC!
Rob
I am currently designing a ADC converter, that will match Dave's performance, and solve a number of issues that plague conventional ADC's - notably huge noise floor modulation, poor anti-aliasing filters, and poor noise shaper performance.
I know from the work with Dave that the perception of depth needs noise shapers of astounding accuracy; indeed, Dave ended up with 350 dB performance noise shapers, in order to ensure that small signals are resolved with zero error - from listening tests, this is needed to ensure the brain can perceive depth correctly.
Now I have designed a ADC noise shaper that exceeds 350 dB performance (note these numbers are digital domain performance only, so it is an idealised noise shaper - I am only looking at the THD and noise of the noise shaper only). To test the noise shaper I can run Verilog simulations, capture the data, then do an FFT on the data, and then check the results. Before I did that, I thought it would be a good idea to run a similar simulation with Dave's noise shaper. In this case, I am trying to evaluate whether it can accurately encode very small signals, so I am using a -301 dB sine wave at 6 kHz. If it can resolve a signal at -301 dB, then we can safely say that small signals are accurately encoded, at least in the digital domain.
So here are the results:
So this is the digital domain performance of the Dave noise shaper, and frequency is from DC to 100kHz (0.1 MHz).
The 6 kHz signal is perfectly reconstituted at -301 dB. You can see a flat line at -340 dB, but this is just a FFT issue. The real noise floor at 15 kHz is at -380 dB, which is about 100 trillion times lower noise than conventional high performance noise shapers. Note also the noise at 100 kHz is at -200 dB - that is extraordinary low for a noise shaper, and shows why I need to do little filtering on the analogue side.
-301 db is better than 50 bits accuracy.
Now to write the code for the ADC!
Rob
Congrats, Beolab!It looks exactly like mine.
Now time to perform the 250-hour break-in!