Not sure where these references to noise are coming from. My Duplex has always operated dead silent. No noise No hum. Nothing.

My filter pack has also been modified with the Roscoe #19 Fire filter, so it's completely safe out to at least 60 minutes (tested), even with the vanes wide open. With an extra replacement bulb stashed for safekeeping, I'm probably good-to-the-grave.

These days the Duplex does, however, share significant time with a DIY red (635nm) safelight, filtered through Rubylith. Some of the VC and/or Eastern European papers like that guy a lot better.