And I forgot to mention that this is true as long as we do not "saturate" the input sensitivity of a power amplifier by feeding it with an inadequate input signal to it.
Here a little experience and intuition is necessary.
A simple series resistor can do the trick, if we know the output voltage and impedance values of the sound source (PC sound board) and the respective input voltage and impedance values of the amplifier we use.
As a general rule, a device such as the Line Out of a sound card will not have problems feeding most power amplifiers.
If there is distortion (excess voltage for the amplifier input circuit), a series resistance of 500 k at 1 Mg will do the job correctly.
Here a little experience and intuition is necessary.
A simple series resistor can do the trick, if we know the output voltage and impedance values of the sound source (PC sound board) and the respective input voltage and impedance values of the amplifier we use.
As a general rule, a device such as the Line Out of a sound card will not have problems feeding most power amplifiers.
If there is distortion (excess voltage for the amplifier input circuit), a series resistance of 500 k at 1 Mg will do the job correctly.
It is not important here if it is the output of a PC, a turntable cartridge or a preamp, Ohmn's Law is one and always
apply
Or do we forget that we cannot couple Bits with analog signals without going through a DAC ?
Impedance matching - Wikipedia
apply
Or do we forget that we cannot couple Bits with analog signals without going through a DAC ?
Impedance matching - Wikipedia
Using made-up values:
If my laptop is at 50% output, then my amp's dial needs to be at 40% to get volume level X. If my laptop is at 100% output then my amp needs to be at 20% to get volume level X. So my thinking was that some speakers might sound better, or at least behave differently, when they get that extra 20% of power from the amp. But I get the feeling my understanding is fundamentally flawed... Are both of those actually putting out the same amount of power?
The speakers end up getting the same power, just with different signal to noise levels. Look up gain matching.
Rob.
nobody said that.. I just mentioned floats and many more bits. That's not equivalent to what you stated here..
Only stating it doesn't make it more true..
While for the completely wrong reasons, academia50 stated the correct answer:
Same voltage + same impedance of the speaker will yield the same power, regardless of where in the chain the gain is applied. As long as you stay within digital or analog limits of the specific devices this applies. So any apparent difference might be found somewhere else: thinks like distortion, noise etc. And then in general(!), you get best distortion and noise figures close to the maximum's of what the devices can do.
Allowing for headroom (program peaks) this, I believe to be true. I'm also thinking, in retrospect, that some of the posters in the thread could have an issue of not enough input power. My setup is a bit older school and if I use a laptop to drive my (separate) DSP I find that the laptop has around 6db lower sensitivity than my separate CD player. Then the DSP isn't operating at optimum levels. Boosting the laptop output just raises the noise floor (here at least). I have equipment to raise the laptop output level. This gives what my DSP wants while allowing for headroom.
Hi Brad. I understand your problem, Doug has stated the same and it's not uncommon. Some speakers just take a little waking up. It's not going to matter what your gain structure is, the speakers just don't sound great at lower volumes. If they are bass shy or a bit forward in the midrange, some EQ will likely help them sound better at lower volumes.
As for gain structure, you shouldn't have any problem running your source at 100% - assuming no EQ or boosts in the source - because you are coming out digital via HDMI. One would hope that your receiver can adjust so as not to clip its own DAC after it has done its EQ.
Like Doug, I tend to set my amp input levels near the loudest music levels I ever want, then let the preamp do the level adjustments. That helps keep a good S/N ratio all the way across.
As for gain structure, you shouldn't have any problem running your source at 100% - assuming no EQ or boosts in the source - because you are coming out digital via HDMI. One would hope that your receiver can adjust so as not to clip its own DAC after it has done its EQ.
Like Doug, I tend to set my amp input levels near the loudest music levels I ever want, then let the preamp do the level adjustments. That helps keep a good S/N ratio all the way across.
I don't see what the wrong reasons are, this answer from robwells is what I think.
"The speakers end up receiving the same power, only with different levels of signal to noise. Look up the gain match."
I just didn't think it necessary to develop the technical part anymore ...
Then why answer BradH's question with "yes"? Yes, noise and distortion will get amplified as well, so if down the line there is more noise, extra noise energy will be present, but that will hardly mean that speakers are driven any harder really. Surely it might not sound the same of noise get audible.
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I missed that, which changes things. The 0 and 1 will not cause problems with the maximum output....
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