I definitely have continuous 58-59 Hz hum (detected by a tuner app on my phone that has freq. readout) with either or both volume controls up. Wearing the bass on a strap, I can rotate and get the bass in a position where the hum all but goes away (exactly like every other single coil pickup equipped bass I’ve owned), but if I turn a few degrees either way, it comes up quickly.
I’ve spent hours and days shielding and grounding this bass. Nothing I’ve done has changed the hum in the slightest. That’s why I’m convinced the pickups are single coil or have only one of the two coils connected to the leads.
By the way, the DC resistance of the pickups are;
Bridge: 9.37 K ohms
Neck: 9.27 K ohms
I have good continuity between the sleeve of a cable plugged in the output jack to the bridge & even to the tuner posts. 0.2 ohms between the jack ground and bridge, 0.6 ohms between the jack ground and tuner posts (continuity through DR coated strings…)