KK CableII-SO Replacement Audio Upgrade Cable Compatible for HD420 HD430 HD525 HD545 HD565 HD650 HD600 HD580 Headphones. 4.4MM Male Balanced Plug. II-SO (1.5M(4.9ft))

This cable is much, much nicer than I expected, especially for the price point. I have bought many cables that were way more expensive than this one that are nowhere near as nice as this one. This KK Cable II-SO Replacement Audio Upgrade Cable truly is a very nice cable. The headphone connectors have a perfect fit, much better than the Sennheiser original connectors in fact. The 4.4mm plug is beautiful with gold and silver accents and a shiny carbon fiber finish. The braided cable is thick, sturdy and supple at the same time. The braiding is exceptionally nice and consistent. The cable material feels great. The cable color is brownish with black and bronze metal components, which goes well with the black and bronze color theme of my Sennheiser HD660S2 headphones and iFi Go Blu DAP -- Killer combination (see picture!). The sound is great too! I am very happy. Definitely recommended above and beyond all other cables I've seen on Amazon for the Sennheiser HD600 family of headphones.

As a music producer who uses Sennheiser HD600 headphones for mixing and mastering on the road, I ordered this replacement cable thinking that a premium price would mean a premium product. Sadly, that was not to be the case. Firstly - and this is my fault for not reading the description properly - the male connector was the wrong size (4.4 mm) and I needed to spend a further £10 for a 3.5 mm adapter.However, what I'm really disappointed about is the quality of the connection on the left earphone. It is loose and the slightest movement causes the signal to drop out so that the audio comes out of the right hand side only. This issue renders the cable useless for critical listening and making mixing and mastering decisions, and as such it is not fit for purpose. I now need to order another cable. Not impressed.

Make sure you have a 4.4 pentalobe inputs on your amp / DAC, because it uses the Sony standard instead of the XLR architecture. This cable is great. It is soft and doesn't make unnecessary cable noises like the cheap stiff cables. Even though it's soft, the materials look very durable for years of use. Plugs are not too tight or hard to push in/out. This is a very excellent quality cable, especially for the price and being 6 feet.

The build quality is pretty fair for this price.It worked perfectly for couple of months and then the left channel stopped working for unknow reason.I use it with a Massdrop HD 6xx paired with a iFi Zen Dac v2.I didn’t unplug my cable from the dac or headphone.If i twist a little bit the 4.4mm pentacon plug on the cable the left channel works,but sadly in many cases not.Next time i will buy some high quality cable.

6/22/2021 Revised reviewAlthough it's not fully compatible with the OEM cable (which is why I am still taking a star off), a small piece of insulating tape on one side of the connectors solves the problem.I love the separation, the sound image, and the multiple reverberation by the traveling octaves (upper harmonics) that produces realistic concert piano sound.This is steal for the price!Original review:While the sound quality improves over the factory cable (this one goes deeper), some of the polished sound becomes extremely moderate (still sounds good enough to make this a keeper). That would be okay with me, because that's what I expected.My major grudge is that it keeps sliding out of my HD 560 Ovation II that uses the same factory cable as the 520, 580, 600, etc., because the connector at the prongs don't provide a snug fit. It doesn't even go into the 520 because of the endge beyong the neck of the connector, something the OEM cable doesn't have.