blargh4

blargh4 t1_j6vnk8l wrote

I don't know about that specific one but computer headphone jacks often have higher output impedance, and the Zero is quite sensitive to that, any significant amount of source impedance will make the make the low-frequency "subwoofer" audibly louder than the other driver.

AFAIK the measurement guys usually use a source that's known to have a near-zero output impedance, like the Apple dongle.

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blargh4 t1_j6ovarm wrote

If there's some kind of accessible bootloader/debug port, maybe, but it'd be a lot of work and you'd probably need to obtain the developer documentation/toolchain for whatever DSP they're using - likely not readily available to random individuals (and probably all in Chinese).

Depending on the chip they use, the firmware could also be mask ROM like ye olde video game cartridges and unmodifiable.

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blargh4 t1_j6kb69r wrote

Reply to comment by pinkcunt123 in DCA Expanse Synergy by LuckyX222

the Expanse is the one planar I'm aware of that doesn't have a flat impedance, so you'd probably get some frequency response shift even assuming the amp's frequency response is flat into a resistive load, which isn't the safest assumption for tube amps.

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blargh4 t1_j6jmezt wrote

Well, understanding this stuff is basically a chapter of an introductory electronics textbook, so that's understandable.

The front panel jack connects directly to the motherboard. It's intended for headphones, so that should be the right place to connect them. It's possible the rear output will also detect that it's a headphone and connect it to the appropriate amp, but I think it's likely to have the same capabilities. There are also line-level outputs, which *may* give you more voltage than the "smart" headphone jack, but they can't drive much current so I personally I doubt you'd get better results with low-impedance IEMs. These audio chips are fairly complex, they mix multiple functions for each jack, and I don't think you can easily find a spec sheet for them, so unfortunately I can only guess.

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blargh4 t1_j6j5n0t wrote

What makes you think that’s where the amp is?

I suspect the headphone jack’s impedance detection feature is probably too “smart” for its own good and is artificially lowering the gain to get you more range on the volume knob.

I would caution against using the line out, it’s going to distort the frequency response with the Zero’s.

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blargh4 t1_j67vpbk wrote

Reply to comment by entivoo in These are not the same by disco_g

People have been researching the audibility of various distortions of audio signals since at least the 50s, we have a pretty dang good idea of what is audible and what is not when measured in controlled conditions in terms of absolute volume, harmonic distortion, intermodulation, phase shift, crosstalk, etc. But most importantly, we know beyond reasonable doubt that human senses are very sensitive to bias, and the humble $9 Apple dongle is unlikely to fare well in a sighted a/b test.

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blargh4 t1_j62ajy2 wrote

“Sufficient” is a question of what you listen to and how loudly. My normal listening level with loudly mastered music is about 75db peak spl and I can’t remember the last time I needed more volume than what a dongle could drive into the HD600s.

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blargh4 t1_j5q4gjl wrote

I don't think that's necessarily true with IEMs. Haven't seen the Hexa measured but the Blessing 2 (which I hear these are knockoffs of) would give you more upper mids and treble with higher source impedance, the impedance rises between 2.5khz-10khz or so.

(could be affecting OP, depending on how shitty his phone is!)

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blargh4 t1_j5nmhtq wrote

>The US site makes no sense (or am I missing something??):

no, it's gibberish, I think something must have got lost in translation between engineering and marketing (and finding this JEITA standard for power measurement is isn't turning up much).

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blargh4 t1_j2fs7kb wrote

In practice, less than we'd like. I would apply the same caveats you would looking at a speaker frequency response measured in someone else's living room. The acoustics of the tiny "room" your head/ears create in conjunction with a given headphone (to say nothing of the subjective qualities thereof) could be quite different. But measurements made on the same rig are useful for gauging the overall tonal differences between two cans... to a point - for example, to my ears my AKG K371s have some very prominent peaking near 6khz I don't see on any measurements made on the GRAS artificial heads.

I've yet to see compelling evidence that at normal listening volumes "dynamics" is something separate from frequency response and your usual illusory differences that have nothing to do with the actual sound.

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blargh4 t1_j2cbpxm wrote

Reply to comment by ZevireTees in Ohm My Lord by ZevireTees

> I don't understand how you would be able to run 1500 ohm headphones

depends entirely on their sensitivity... possibly very easily.

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blargh4 t1_j2c8fdq wrote

Sennheiser HD6XX (or HD600 if you find it on sale, $350 is a bit steep when the 6xx is $200) is a pretty safe choice.

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