[andrew7316]

Years ago I had an Aune DAC/headphone amp; I'm thinking it may have their first USB amp, but I cannot remember for certain. Regardless, I can remember hooking the thing up and being utterly underwhelmed by it, additionally, it had a lot of little glitches, such as the line-out not working, or only working partially.
 
I was completely disappointed in the product and wanted a refund. However, as I discovered, the problem wasn't the Amp, but rather the power supply: it simply wasn't delivering the right amount of power for the Aune to perform as it should. Since this incident, I don't think I've ever had an issue with a miss-matched power supply, but that is in part because I now pay attention to this, whereas I used to think along the lines of, "If the little lights come on, it's working."
 
So as a general question to those who have a lot more experience with headphone amps than I, how important is the power supply in terms of sound quality? Consider for a moment that my aforementioned experience could be considered a stupid mistake: I was using the wrong power cable, and this could mess up any electronic device; fine. However, is there actual merit, in terms of sound quality and overall performance, to tweaking one's power supply?

 

[psun786]

Years ago I had an Aune DAC/headphone amp; I'm thinking it may have their first USB amp, but I cannot remember for certain. Regardless, I can remember hooking the thing up and being utterly underwhelmed by it, additionally, it had a lot of little glitches, such as the line-out not working, or only working partially.

I was completely disappointed in the product and wanted a refund. However, as I discovered, the problem wasn't the Amp, but rather the power supply: it simply wasn't delivering the right amount of power for the Aune to perform as it should. Since this incident, I don't think I've ever had an issue with a miss-matched power supply, but that is in part because I now pay attention to this, whereas I used to think along the lines of, "If the little lights come on, it's working."

So as a general question to those who have a lot more experience with headphone amps than I, how important is the power supply in terms of sound quality? Consider for a moment that my aforementioned experience could be considered a stupid mistake: I was using the wrong power cable, and this could mess up any electronic device; fine. However, is there actual merit, in terms of sound quality and overall performance, to tweaking one's power supply?

Most today's amp come with a dedicated power supply, either build within the unit or as an seperate block. The design and quality of PSU is "essential" for a good amp and probably one of the components that people pay most attention when they look at dissect pictures. But what ever the manufacture decided to include should be sufficient for the circuitry & not meant to be altered... Unless you are a modder & know exactly what you are doing.

High-end audiophile does "upgrade" their power cable sometimes (better shield from electric interference) ... These can get very expensive and rarely improve the sound quality (but very sexy) unlike audio cable.

 

[OJNeg]

Power supplies are used for almost everything. Let's start from the beginning. Your wall outlet will deliver 120 Volts of alternating current (assuming you're in the States). That's enough volts to give you a nasty shock. However, most electronics normally don't need 120 volts, OR alternating current. This is the first purpose of the power supply. I'll try not to get too technical, but basically the primary of the transformer is connected to the AC outlet, and the secondary of the transformer will essentially step down from 120 V, to whatever you need. Great, now you have the appropriate voltage, but you want DC instead of AC. Next will come a bridge rectifier, which essentially converts to DC. Then the power supply board is what regulates the voltage and supplies power to the amplifier board. If I've lost you, I suggest you read up on transformers and bridge rectifiers, it's actually a very simple process.
 
Do you have a laptop? Notice how you don't connect laptop directly to outlet, because you need that big stupid power brick? Well, that brick is essentially a step down transformer and a bridge rectifier, which supplies the power that your laptop needs. You'll notice that some headphone amps are designed to run off these sort of power supplies instead of having their own transformers. Others will have their own step-down's and power supplies.
 
Now to answer your question more directly, yes, power supplies do matter. They can introduce noise into the amplifier section, which is obviously a bad thing. Rule of thumb is, you want a reliable, regulated power supply to feed into your amplifier.