Is it possible for a power supply to affect sound quality?

[manueljenkin]

The place to start with would be to understand how a transistor behaves with power supply fluctuations.

 

Start with the most abstract model around. Ideal power supply. Then look into one level deeper but still a abstraction - power supply rejection ratio. Then start looking into non linear power profiles of transistor operation, their internal capacitance resistance parameters etc and quantum effects.

 

In short, yes power supply quality will affect sound.

[manueljenkin]

Speaking of good quality SMPS, I think burson fun should be given a chance. Really inexpensive and sounds great.

[manueljenkin]

7 minutes ago, John Dyson said:

It is more about how a circuit all together, including power supply functions.   Few circuts contain a transistor by itself.  In fact, when we start talking about 24bits of resolution, everything in a circuit needs to be considered, including the circuit board being a part of the circuit.  After you do a bit of upper RF/lower microwave design, which still has similar aspects to 'normal' circuitry, you start thinking of a circuit in a more holistic standpoint.   That trace is part of the circuit just as a big fat inductor (depending on where in the circuit.)  Even the layout or even 3d space in the circuitry itself is part of the circuit.

 

One problem that apparently happens is that the traditional concept of a audio frequency schematic representing a circuit that is in an environment with non-audio frequency aspects.  Often, an 'audio only' design will result in vulnerabilities.    To be safe, you use an RF (probably UHF/lower microwave) sensibility when looking at the circuit as a whole.  Of course, the proportions are different than an actual microwave design -- but the fact that layout might have to e carefully considered.   This 'layout' thing also extends to power supply characteristics,  (Please, if you REALLY want reliable low noise -- use a shielded transformer.)

 

Similar in concept is when you design an RF amplifier, a more optimal, linear design will be created if the audio frequency & lower characteristcs are considered (e.g. intermodulation distortion.)   There are concepts where audio-range feedback is used in an RF-only amplifier to mitigate certain kinds of distortion.

 

I haven't done an EE design in decades, but one thing that I found -- often, it is more complex than the superficial picture on a schmatic.  Don't think in terms of 'parasitics' in the deisgn, but instead the components that used to be called 'parasitics' are a natural part of the design -- sometimes actually considered as part of the schematic.   Of course, great experience EVENTUALLY support shortcuts, but too often it seems like the experience/developing expertise step in career evolution is skipped -- then we end up with fragile combinations of componentry..

 

John

 

Agreed 100%. Transistors are very pedantic devices in terms of behaving wild to random aberrations. A high frequency noise can still harm the normal functioning of transistor even if our input sigal is in audio band.

 

Benchmark had an article on RF noise consideration when designing their amps.

[manueljenkin]

A couple of doubts to Stephen JK and and Jonh Dyson.

 

Isn't a choke actually an R-L circuit (something like what is used in tube lights starters).

 

I have doubts about using ferrite beads/chokes in power lines. While they can help limit high frequency signals and hence hf noise, won't they also slow down the transients of power delivery. Considering transistors power consumption cycle is complicated, I do expect it to change the performance a little.