[wildebassman]

I know there are fluctuations in the voltage from area to area and even sometimes within your own system from time to time, when for example the the voltage drops or goes up by 10% will this affect the playback on my cd player, will it play the music at a higher or lower pitch?
Please clearify this for me.

Thanks,

Dennis.

 

[balou]

most likely the voltage will fluctuate because some other component in your cd player needs current. because there is no such thing as a perfect power supply, voltage will unavoidably drop if some components need instantly a high current.

local voltage changes don't occur that often (only if you move from an area with 220v to 230v or so), and because they are after the regulated power supply in your circuit, they mostly do not matter that much.

and long time voltage changes do not really matter either, as long as the voltage is above the minimum working voltage the opamps/dacs/etc in your player. as said above, the power supply filters and regulates down the voltage to a much lower voltage anyway

the problem are the very short time voltage fluctuations (from local components, as said above).
imagine this: the DAC chip needs a stable reference voltage, often 5V. it then routes this through a resistor network which operates as a voltage divider. this is how the analog sound is generated. now, if say for example the voltage isn't exactly 5v, but fluctuates around 4.99 and 5.01v. this also means that the output of the dac will fluctuate too - this is to say the volume. roughly saying, voltage equals volume. so with a fluctuating voltage in your cd player, volume will also fluctuate. and you may know the effect of fast-fluctuating volume by the name "noise"

oh and it's the same too with for example the opamps: fluctuating input voltage, fluctuating output voltage, and voltage equals volume.

so no pitch change, mostly noise.

 

[DaKi][er]

Your cd player has a crystal oscillator that sets the timing of everything, these things are really quite stable in their frequency and changes in voltage and temperature don't change their frequency much at all, and all these changes are 100X less than the amount needed for anyone to be able to perceive a change in pitch at all

Further, just about everything has all its power fed through regulators that cut out a massive amount of the voltage fluctuation and output stable voltages that everything run off there after

 

[wildebassman]

I ask this because I want to put a line filter in my system, most electric devices now in Europe are said to work on 220-240 volt, I measured 225 volt in my house system and I want to put this device in front of my amp and cd player that's why I asked:

http://www.china-highend-hifi.com/prod0212121723.htm

Cheers, Dennis.

 

[mono]

Your CD player has it's own integral power supply. What's that supply like? If for example it's a switching type, the incoming AC noise is pretty irrelevant compared to noise output by it, and the supply's output remains regulated to the proper level without concern for what the input voltage is, so long as the input voltage level is *high enough* for the supply to function properly (which is certainly the case at 225VAC on a PSU spec'd for 220-240VAC.

Such an add-on filter might make the most difference on an unregulated supply that varies output based on input and has no particular consideration for line noise. Your amp could fall into this category (depending on it's design) but it seems unlikely, and I doubt the CD player does. If uncertain about them you might examine their PSU subcircuits or for the amp what is spec'd to power it if the PSU is not built-in.