I recently ordered some OPENHEART 4.4mm balanced cables for my Hifiman Ananda Stealth. I couldn't decide between the 8-core and 16-core cables, so I bought both.
The weights are as follows:
- Hifiman original: 51g
- OPENHEART 8-core: 37g
- OPENHEART 16-core: 56g
I tried to measure resistance, but my DMM has some low-ohm drift. As far as I could tell, all cable connections were roughly somewhere around 200 milliohms end-to-end (correcting for lead resistance). I know there are methodologies for more accurate measurement, but honestly I think all these cables are sonically indistinguishable.
All three cables were extremely flexible. The Ananda Stealth came with Hifiman's updated cables that address the complaints about their previous stiff cables.
I was surprised at how flexible the 16-core cables were. The 8-core cables were so "stringy" that they had a tendency to tangle when unhooked. The relevance of this would depend on whether you left them connected all the time or connected/disconnected/packed them up in daily use.
Anyway, that's it. I figured I'd share since I had both in my hands.
My opinion is to consider these factors: (1) looks (2) connectivity (tips, connectors, etc. ) (3) physical characteristics like length, weights, kinkiness, microphonics, etc. ) and buy based on those. I doubt there is any meaningful electrical difference between most reasonably decent cables. Airline freebie headphones? Probably junk cables. Hifiman or decent 3rd party cables, probably all fine electrically.
There are a few things that make a cable influence sound:
It's important to use oxygen-free copper. Crap copper can lead to channel imbalance
It's important that they're built properly. Well-soldered, gold-plated. Bad electrical connections = bad signal transmission.
EMI shielding if needed. If you live near a radio tower, every wire is an antenna and will pick up interference. Similarly, if you live in an apartment building and you have 30 WiFi networks all around you.
Fortunately, none of these things are expensive. You can tick all these boxes in a $10 cable, easy. Everything else is just snake oil or aesthetics.
EMI shielding is only relevant if you expect interference in the frequency region that you are working in.
If you want to transmit a 2.4 GHz signal, then your cables should be very well shielded - there is a lot of noise in the 2.4 Ghz band (since you will always have WiFi and Bluetooth devices nearby which operate in this range too)
But there is no relevant electromagnetic noise below 20 kHz - and in addition to that, the impedances we are working at to connect headphone to amplifier (much less than a few hundred kiloohm) are low enough for EMI not to be an issue (since the stray pickup current will be many orders of magnitude lower than the current of the actual signal)
Oxygen free copper cables aren't humanly distinguishable from a coat hanger last I checked. So I wouldn't really call that important. But if it's cheap anyways, why not?