Should cable length affect ohms very much?

evilsofa

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I've got a Fiio E6, which is a tiny little headphone amp that outputs 16mW when under a 300Ohm load, and 150mW under a 16Ohm load. I've been using it with a 15 foot long 3.5mm 22AWG extension cable from Monoprice and a pair of 25 Ohm IEMs with no problems. I needed to increase the length of the cable, so I got a 25 foot long version of the same cable. It didn't work; with the volume all the way up, I would get a bit of sound all distorted.

Is the new cable just a bad cable? According to this calculator, at 22AWG, a 15 foot wire makes 0.242 Ohms and a 25 foot wire makes 0.404 Ohms. Should that be next to nothing as far as the amp is concerned, or is there something I don't know about Ohms?
 

evilsofa

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After sleeping on the problem, I realized I have a PC to test the cable on. Duh. I've found that the issue is something else entirely; the IEM's plug is slightly too small for the jack in the extension cable.
 

OFaceSIG

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Anytime you're dealing with an analog signal quality and length of cable can have an effect on the end product audio.
 

B00nie

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Anytime you're dealing with an analog signal quality and length of cable can have an effect on the end product audio.

While that's true, generally with these lengts issues like the OPs should not exist. Audio cables are not subjected to only resistance but also impedance and capacitance (reactance) which make things considerably more complex. Still I think OP found his problem with the non-standard plug size :)
 

xCWolf

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If you have a DMM/VOM you can just measure the resistance. cheap ones at harbor freight are like 6 bucks and it should be accurate enough for that.
 
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