Your assumption there is very, very accurate!
You can read more about the Electro vs. EM64 comparison in the comments section of the Electro review. I'll copy it here for all to see:"The EM64 is quite a bit sparklier than the Electro. The top-end is brighter and bites more, so I’d say the Electro’s top-end is more transparent (i.e. it changes more from one track to another). Obviously, that’s a quality that would be more ideal in mixing, so you can track the differences you’re making more accurately in real-time.
The EM64’s midrange is also a bit more distant, which gives its soundstage a bit more depth. As I said in the review, the Electro’s upper-mids are a hair more forward than flat-neutral. If your engagement is determined by dynamic energy and the contrast between the top- and bottom-ends, the EM64 is more fun and lively to listen to. The Electro’s reference-tuned low-end can make it sound straight-up dull down-low with certain recordings. But, if your engagement is determined by the fullness and intimacy of the vocalist or lead instrument, the Electro’s more forward, vibrant midrange will come across more engaging.
With all that said, I think the EM64 is more ideal for performing than it is for mixing, even though it can serve that function capably too. I feel the reverse is true for the Electro. If you like a touch of brightness and a bit of bite to your IEMs, the EM64 is for you. If you prefer a slightly thicker, smoother, but no-less-detailed sound, the Electro is the one."
