I might be able to provide some clarity from my experience. I received my iSine 20s at the end of last week and have experimented around with a bunch of different sources, amps, both cables etc. The majority of my listening is either coming from an iDeivce or my computer using streamed music (mostly tidal hifi or mqa masters, but I've also listened to Apple Music and Spotify with the isines).
While my iPhone 7 plus can drive isines using the standard 3.5mm cable and the apple lightning to 3.5mm adaptor, the cypher cable sounds MUCH better direct out of the iPhone. This makes sense given there is a dedicated dac and amp in the cypher cable. However, I have found that the isines scale very well with amplification using the 3.5mm cable, so if I connect my iphone to my dragonfly red (via apple usb 3.0 cck), ha-2, or mojo, the isines sound just as good or better than they do straight out the cypher cable. With the DFR, the sound is pretty comparable. To my ears, the instrument separation is a little better and things are generally a little tighter with the DFR, but I prefer the decay out of the cypher cable. I prefer the sound of the 3.5mm cable through the mojo than through the cypher cable alone, although the cypher cable is closer in quality than it has any business being.
All this is more of a reflection of the really great job that audeze has done creating synergy between the cypher cable and the isines. To me it is remarkable that a $50 cable can suddenly get similar response out of the isines as a $200-$500 portable dac/amp; however, if you are using a source with a solid dac and amp, you will be very happy with the isine 20s using the standard 3.5mm cable. Hope that helps