[Android Software Development] ephexxis:
okay ill break this down for ya. it is pretty confusing thinking about gain vs volume, digital vs analog, etc when you consider all these tools we've added to the process.

Digital Gain. Also referred to as Preamp(lification) gain. The songs you have stored on your phone are obviously digital media files. data. bits comprised of samples and timecode data. when it was encoded in digital and perhaps compressed, the engineer already did a bunch of processing to clean up the data and normalized its gain as part of the process. Digital, or preamp gain is something you can adjust now that you're trying to play back the file, which is ultimately converted into an analog signal (electricity) so it can power headphone/speaker drivers and physically recreate sound. DG is referred to as preamp gain because it occurs before the data is sent to your DAC, which is where signal amplification would occur if you were using an amplifier, like with most of these portable DACs we have discussed.

the reason its always safe to attenuate (tune downwards, reduce) preamp gain is because it affects the entire digital data set, which has been normalized. try to visualize for a second, the image of an audio waveform. raising the digital gain is like boosting that waveform up above where it sits normally while the normalized dB range (there are better terms for this but I'm having brain issues), remains static. essentially because the digital file has a compressed dynamic range (you could think of it like a static range really, though I'm not sure that's an actual term used), moving that waveform up into the ceiling and beyond causes it to clip, get distorted, and for the purposes of conversion to analog, destroys the fidelity of the data.

when you amplify an analog signal, you're increasing the power of the signal, as its being sent to your listening hardware. since this part happens after the digital data (ideally enhanced and purified to your liking before have) is has been turned into a physical electrical signal, applying amplification is boosting the power of the converted data which at that point as had as much of the noise and stuff either processed out or compensated for by the user. so the electrical signal produced by your DAC is pretty clean and to recall the earlier waveform visualization, amplifying the signal is like moving that information up, like before, only the range it sits in comes with it. so with a proper attenuation of preamp gain, you increase your headroom such that you can amplify the analog signal quite a bit and you're not affecting the bad data, or pushing the audio into that ceiling anymore.

TL;DR digital gain = the gain of your music files before converted to audible sound

Signal amplification = more power to analog audio signal once it's been converted.

Hardware gain = the volume setting on your phone. if you lower digital gain you can set the volume to whatever because this is also amplification just done by your phones onboard hardware, within whatever confines are built in.

hope this helps.

---------- Post added at 07:08 AM ---------- Previous post was at 06:57 AM ----------

HTC may be doing poorly as a company but they have made some excellent phones that are highly regarded by the people who owned them. I'm encouraged by google contracting with them, it's like the leg up they needed to get back in the game, and with the phone's carrying stock android, the UI component is a nonissue and they get to focus on just hardware. I'm excited to see what they put together especially in the onslaught of midrange powerhouses that keep being announced. it'll be a while before i buy another samsung device, with all the way more affordable and dev friendly handsets becoming a mainstay in the market.