OP
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I'm interested in reducing absolute amount of noise. Does higher voltage power supply reduce absolute amount of noise?
If I turn the volume knob to 3'o clock, the amplifier noise floor doesn't get reduced, but the noise floor of the source is increased. But, the amplifier noise floor is higher than the DAC noise floor anyway.
How do you know this is the case? How is the volume knob on the amp any different from a passive (stepped) attenuator between DAC and amp?The pot is adding noise and distortion at 9 o'clock, and not wide open, less at 3 oclock, way more than anything else in your system, then it's being amplified at full power.
Just look at the ASR review of your amp again.How do you know this is the case? How is the volume knob on the amp any different from a passive (stepped) attenuator between DAC and amp?
I'm thinking about upgrading AIYIMA A07's power supply to either Mean Well RS-100-24 or Mean Well GST60A24-P1J.
RS-100-24 doesn't have to be grounded. GST60A24-P1J has to be grounded.
Yes, this is the correct way to look for leakage currents.When AIYIMA A07 is floating, if I rub the metal case, I feel electric zaps on my fingers.
I don't get this. Doesn't reducing amplifier volume reduce noise floor of the source as well?
Why ? Noise floor is only a problem when it becomes audible and is determined by transducer sensitivity.I'm interested in reducing absolute amount of noise. Does higher voltage power supply reduce absolute amount of noise?
How is output voltage of Topping D10s 1.6V at -20dB or -16dB?You're at 1.6
Does the potentiometer on the amp add more absolute amount of noise at 9'o clock than at 3'o clock? Or, is it the noise relative to signal?The pot is adding noise and distortion at 9 o'clock, and not wide open, less at 3 oclock
This means the noise relative to signal increased as the volume on the potentiometer decreased. The absolute amount of noise stays the same in theory.As we lower the level on Sys, naturally the measurement noise as a percentage rises leading to the graphs that you see. In other words you lose signal to noise ratio with passive volume controls.
I still want to decrease noise floor of the amp. But, TPA3255 measurements do not include noise floor at various voltage levels.Why ? Noise floor is only a problem when it becomes audible and is determined by transducer sensitivity.
I don't know what this means.The grounding is ONLY for the mains filtering.
Between reducing DAC volume and turning down the amplifier volume pot, which one introduces more noise to the entire system? I guess both introduce roughly the same amount of noise unless the amp volume pot actually injects more noise at lower volume levels.The noise floor of the amp is determined by the noise of the amplifier circuit, PSRR (Power Supply Rejection Ratio) of the amp circuit and its internal power supply decoupling/regulation.
I don't know what this means.
That means the power supply is leaking any current to the electrical ground? Is it not good enough? What can go wrong? Should I connect the amp case to the electrical ground even if the power supply is grounded?the safety ground is only connected to a filtercircuit in the power supply on the 115/230V side
Probably AI that made that claim or someone that quoted a response from AI (or Paul or similar 'guru') that made a comment not actually related.Does it help to use a grounded power supply, then? Someone else pointed out that it protects RCA cables and PCB print-outs from being burnt.
If a power supply grounds itself through RCA cables, would RCA cables not pick up some noise from the power supply? I know AIYIMA A07 is grounding through RCA cables unless it is paired with a grounded power supply. The power supply noise is routed through the amp, the DAC, and my computer to the electrical ground.A 2-prong and 3-prong power supply that has a DC output both are isolated from mains.
If a power supply grounds itself through RCA cables, would RCA cables not pick up some noise from the power supply? I know AIYIMA A07 is grounding through RCA cables unless it is paired with a grounded power supply. The power supply noise is routed through the amp, the DAC, and my computer to the electrical ground.