from an electrical perspective, we should first determine the load(headphone/IEM), and then make the amp section to go with it. knowing that some loads will make the pairing job a lot easier.
so the concept of amazballzz DAPs without consideration for the headphone/IEM can look a lot like empty marketing nonsense.
most TOTL DAPs like the sony stuff have been consistently misleading people with eye candy. highres, whatever cable nonsense inside the DAP, and fancy chipset tech that doesn't really deliver. look at that graph we pulled out of our asses that no engineer would ever support, it means not a thing, but hey doesn't it look like we're selling something great?
they can't stop talking about all those irrelevant stuff to get us thinking it should matter. they hope we'll go aggro on fake targets and forget about what really matters, which is the signal getting out of your headphone, the actual sound. hires DAPs being one of the fake target to focus on. a so called highres DAP is a DAP that can
play highres files. nothing more. there is zero guaranty about a DAP having highres fidelity at the output jack, and even less about highres at the output of the headphone/IEM. and that's for an obvious reason, almost no portable device will do better than 16bit on most measurements once plugged into the load(IEM) at the user's loudness setting.
the ZX1 and most sony DAPs talk non stop about highres, the highres golden logo, the highres icon on the screen when you play highres file, the special chipset and special DAC made for better highres and lower noise. but then you measure the output of the DAP even unloaded and you get close to the specs of an old iphone(who am I kidding, an iphone is always old, think different). so it's worth keeping in mind that in front of marketing tricks, we're not all Pen&Teller and we get fooled way more often than we would wish.
now some cellphones have horrible sound, some have very audible hiss with most IEMs, some have way too high an output impedance and it messes up with the signature of many multidriver IEMs. some will distort when the IEM has too low an impedance... and so will some DAPs!
I'm not saying that cellphones are the dope and that DAPs are for stupids. just that if you care about features, buy for the features. but if you care about actual sound fidelity, then buy for measured fidelity into a specific load, not because some marketing guy gave you the illusion of fidelity with a few gimmicks.
but that's me daydreaming, as DAPs typically don't show measurements into loads or any significant measurement for that matter. oh well, there you go, now you know that almost nobody is actually selling high fidelity. if they did they would give the specs that really demonstrate it, they would love nothing more than to show how they do what the other guy doesn't many countries even allow that kind of advertising "buy us because the other brand does only this". instead we get misleading badly written and incomplete nominal chipset specs, as if it was what you should expect getting out of the headphone jack. because it's BS but legally it's not, they just don't say clearly that it's the measurement from the chipset manufacturer. or they only write the one spec that looks ok, and "forget" to put down the other ones on the website. misdirection, magic trick, we're amazed. marketing is magic.
so what should I do?
maybe if I'm ready to put 2000$ into a DAP and perhaps as much into IEMs, I could first put 450$ into a QA401 audio analyzer and a few resistors and cables to check myself the fidelity I get out of those DAPs.
maybe I'd get some expensive DAP, because why not I have the money. it looks nice and is nice to use. that's already a good reason to get it. if people look at me in the street like they wish to steal it, then I'll feel special for a time, maybe I'd enjoy that too.
or maybe I'd get a good DAC/amp that will work well with my headphone, and give me a sound that is objectively or subjectively better than any DAP alone.
or maybe I can't be bothered with carrying bricks, portable gear shouldn't forget the portable part. so I'll just get rid of my TOTL IEM that's such a bother to drive well with a non hissing, low impedance non distorting source, and instead get a portable headphone, easy enough to drive so that I can use it with my cellphone. life is simple, life is good.
maybe it's just to commute anyway so who cares about sound fidelity when overwhelmed by noises. maybe I'll just get cheap isolating IEMs, or just ear plugs. maybe I'll just listen to audiobooks anyway so who cares about fidelity and I'll use a pair of etykid IEMs into my old sansa clip. greatness for 2 digits(true story bro).
people have choice and they all want something different. science will not tell me what I desire. I'm not that objective yet ^_^. at best it can help not being fooled as often as without science. but even that doesn't matter to everybody. some are fine with being fooled if it makes them happy. the question of what to buy goes way beyond the question of best sound. and even then, what is best sound with headphones? we don't even have a frequency response target we can confidently say will sound neutral to your ears. so we can rely on objective measurements to follow an ideal, but when that ideal is unclear(up to a point), you listening to the gear and you using the gear will still be a big factor in how much you'll value a device. believe me I wish there were simple answers "go buy this and this and you'll have the best sound ever". but I'm not aware of enough measurements done to determine such combo, and even then I bet we wouldn't all buy the same stuff. we're just that kind of creatures.
