So consider me a noob with little knowledge in electronics/physics/amps for this one. But Im a good kid so don’t be mean to me .
Here’s a bunch of questions I would love some answers explanations to.
I have a liquid spark DAC and AMP. So the DAC gets input from USB and I believe uses a power supply for power. Now the DAC RCAs out to the AMP.
Now I believe the DAC works at its specified voltage to do its job and uses some sort of VRMs to achieve this voltage, correct?
Now the DAC outputs a signal to the RCA which has some voltage. What is the voltage here and what determines it?
Does it send more voltage if I turn my Operating Systems volume louder? (the DAC has no volume control on it).
If the voltage does indeed get higher the louder you go, is there a limit? Is there further voltage regulation at this point?
For example I understand that audio interfaces work using more voltage than straight up DACs and they have a volume knob. I hear the more you push the knob the more voltage goes out, I have heard numbers up to 5V.
Signal enters the amp via RCA connection. Does the AMP do any voltage regulation at this point? Is there a limit as to how much or how low of a voltage it can receive to function?
Amplification happens, boosted signal goes out to headphones. A lot of measurements consider a 2V input to the amplifier (Why?) to do measurements on the output.
What if I manage to get a higher input to the amplifier lets say 5V, does this mean I can expect more power than others have measured in the Amplifiers output?
Am I going to get better or worse measurements in this scenario (SINAD etc…)?
Firstly a DAC translates the digital signal of 1s and 0s into a analogue voltage. The “normal” line Vorlage that you will see with an RCA Output is about 2.1V. that means that a full scale signal, so only 1s should give an effective voltage of 2.1V while only 0s would yield 0V on the RCA’s. The audio signal moves in-between that.
Lowering the volume on the Operating system recalculates the digital value resulting in a lower amplitude sent to the DAC. If you digitally louden it the amplitude will rise towards the limits of the dac (the usual 2.1V) until it clips of the upper part of the signal.
Regarding the “voltage regulation” it’s more like the DAC chips produce the correct voltage directly with an added output stage that amplifies the signal a fixed value towards the rated output.
The Amplifier input will depend on the design. There are times it will be amplified a fixed amount and then via the volume knob leveled down towards the output stage, while other times the output stage in itself gives of the gain with the RCA input directly on a FET gate.
The 2V input for the Amp measurements just reflect the standard line Signal which is usually what an amp should be designed to so the measurements give the amp the best case scenario since the high input signal will give a good signal to noise ratio for the amp.
Some amps can deal with a lot more signal while others will clip and be very unhappy with you.
Usually more input should yield better SNR until something gets overloaded at any point. Thus source volume control should be avoided and output stage volume control should be the best.
But the difference is negligible with decent equipment and outside of edge cases
Right this does clear thing up a lot actually. I think I am starting to grasp the whole process way better.
So the DACs then are designed around the fact that a standard digital signal from devices (regular consumer devices at least) will equal to about max 2.1V analog signal after complete processing and maybe slight amplification.
So the AMPS then are designed to expect a line signal anywhere from 0 to about 2.1 V to amplify. Thus measurements and performance are measured from a 1 to 2 volt input as expected.
In the case of a high voltage input resulting performance would be better but amp internals (and especially headphone amps I guess) are basically 99.9% chance not designed to handle a much bigger signal so something would overload.
Pretty much yes. But whether an amp is capable of dealing with more voltage is simply down to the specific amp. I remember some Topping or SMSL amp which specced its power output with like 4V input which is kinda disingenuous imo.
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