HD681 with Ipod Nano 2gen. Output impedance?

[lorriman]

Does anyone know the output impedance of the 2nd Gen Ipod Nano?

I am looking to get a friend the HD681 headphones but their impedance is a mere 32 ohms which means that if the 2nd gen nano has a high output impedance, and I expect it does, then the audio will be affected.

I've tried searching on the web to no avail.

 

[sundial911]

http://gdgt.com/apple/ipod/nano/2nd-gen/specs/
According to this website here and the apple website, the impedance of the ibuds is 32 ohms. There is no given output impedance for the 2nd gen nano. So probably the HD 681 will sound nice with the nano but from personal experience it will work better with an amp. Even a cheap amp like the e5/e6 will do.

 

[lorriman]

Thanks for that attempt. I think I probably posted in the wrong forum.

 

[lorriman]

hmm, forgot about his thread. For anyone accidentally bumping in to it from a search, I tested the Ipod Nano 2nd gen with the required resistor and multimeter and it has an output impedance of 9. That means that it will produce a small bass boost at 80Hz with ibuds (and the HD681) and some minor treble roll off, plus slightly flabby bass overall. Not ideal. A very poor match for balanced aarmatures and even for typical consumer IEMs. Need headphones of 80Ohms impedance for good audio repro, or else match up the Nano with the Fiio E5 amp, which corrects the high output impedance and which itself is near hifi in performance despite the very cheap price (which is probably why Westone 3s where bundled with it). That amp isn't a bad idea for higher impedance phones as well, since the Nano doesn't have much gain/voltage which means likely volume issues.