Noble K10 Universal measurements: https://clarityfidelity.blogspot.com/2016/08/noble-audio-kaiser-10-universal-new-ver.html
Impedance dips to around 14 Ohm at around 10KHz, which means it'll draw less voltage there than anywhere else on its FR, which explains the 10KHz dip. It also means that a typical 2 Ohm output amplifier will slightly overdampen the 10 Khz region, resulting in slower-than-normal decay of those frequencies.
Whether that produces desirable SQ or not... ¯\_(ツ)_/¯
Ideally, it looks like you will want to drive these through amps that have 1 Ohm or less output impedance.
junkiTypically you should have an output impedance that's 1/8th the earphone's impedance. 2 ohms won't be the end of the world, and 10kHz isn't the worst place to overdampen.
The Campfire Audio Orion and Andromeda are between 4 and 8 ohms in the bass region - THAT'S bad news.
junkiI tried the Andros with a phone that had over 2, maybe 5 ohms OI, and I was amazed at how awful it sounded. Razor thin bass, with snare drums that sounded like they were being hit by pencils. I wish I used something more suitable.
thefitzThere has formed somewhat of a consensus that around 2 ohms is ideal for the Andromeda, and that typical 'audiophile' devices with really low impedance are too bassy - of course that really depends on what you want out of it. I have a set of Novas that I tend to prefer with lower impedance, but I think they are tuned with less bassto begin with.
The shame to me isn't just that phone outputs are inconsistent and often higher than ideal - it's that theres usually no information about that, and also no information given about IEMs until measurements are taken, often just by hobbyists. The 64 Audio range is a great example, with most of them tuned for really high impedance you get with stage monitoring gear. But of course the consumer market didn't know that, and the impression of nearly the whole range was dark, bassy, and veiled to some.
Thanks to junki for spreading this info specific to the K10. Will be interested to see if any of my sources have that effect.
Impedance dips to around 14 Ohm at around 10KHz, which means it'll draw less voltage there than anywhere else on its FR, which explains the 10KHz dip. It also means that a typical 2 Ohm output amplifier will slightly overdampen the 10 Khz region, resulting in slower-than-normal decay of those frequencies. Whether that produces desirable SQ or not... ¯\_(ツ)_/¯ Ideally, it looks like you will want to drive these through amps that have 1 Ohm or less output impedance.