Hi.
I like the Morrow MA3. Unfortunately, it's unshielded and despite its sonic advantages, the hum is a bit much.
I suggest you to contact Morrow Audio to find out why it hums.
With signals so small, I think you are going to need to get a shielded cable. Not much more to say about that. Not sure why you thought you could get around that requirement.
Sorry, I disagree.
Given built properly, an unshielded audio connect should NOT hum at all. Needless to say, it should not be too long. Otherwise, it'd hum even with triple shielding over it. Shielding generates extra conductor-shield capacitance, which rolls off HF. Sonically, the music sound compressed & less lifelike. I hate the sonics of shielded cables.
Take mine for example, the 6 pairs of audio interconnects I DIYed & am using for years, are 4N pure solid silver conductors, NO shiled at all, including 2 pairs of interconnects from my TT to my 2 tube phono-preamps. No hum - provided they are built right!
c-J
PS: Pure silver cables sound superb. But you may ask how come pure silver
cables are rarely available in the marketplace. One practical answer is: way way too costly to build & very dfficult to keep pure silver from tarnishing.
Thank goodness, I know the way to overcome them.