Audio interference from 5D PSU

I have external Focusrite Clarett Audio interface this accepts my audio inputs and supplies signal to my external speakers. This uses Thunderbolt as a main connection to my Mac.

When I plug in the Drobo 5D (Thunderbolt) and power it up, I’m getting audible interference out my speakers. If you listen closely to the actual power supply the same noise is being produced.

Drobo have kindly supplied 2 additional power supplies so now I have 3 and they all behave and sound differently.

The original power supply makes an audible noise after about 3 hours of being on.
The second makes noise all the time.
The third also makes noise all the time but not as loud as second.

The noise is a high pitched whine. Not 50hz hum.

This leads me to believe that I’m never going to get this sorted using Drobo power supply??

I’m also disappointed with the fan noise from the 5D, I have to switch the Drobo off completely when recording using microphones in the room.

Has anyone got over these problems with audio gear?


That sounds like probably out of the typical Drobo owner’s use experience. As for the power supplies, perhaps some sort of power conditioning before or after the Drobo power supply?

If the fan is too noisy (they’re definitely not silent) then maybe moving it to a soundproof closet when recording?

hi steveroyall,
just to also add a note, i have done live recording with drobos before and never had that problem.
the only possible differences are that the connection was usb instead of firewire, and in the uk it had a uk plug socket with a surge protector.

maybe if you can try usb as a test, or can look into how to best add surge protectors in the mix (so to speak), does that make a difference at all with the noise?

edit: it might also be worth trying another power socket in a different room too, just in case that socket, or power ring, is possibly the cause too?)