Picked up some 120 Ohm 2W resistors and installed them inline with the fans. This effectively dropped the power to the fans from 20V down to about 12V. They run almost silently now (as designed) since they are intended to run at 12V being PC case fans.
There is something almost magical about having the projector be so quiet. If you get close to the fans, you can hear a gentle ‘whoosh’ sound – but that’s it. Not enough to intrude on the movie at all.
We watched Austin Powers (the original) — I checked the temperature during the movie a few times. After running for 2 and a half hours (there was some amount of warm-up) — the internal temperature was only 5C higher than it was with the original fans. Safe enough for me.
I’ll keep monitoring the temperature(s) to see that its stable. I’m sure that once I ceilnig mount the projector things will change a little as well.
The next modification will likely be some HVPS maintenance and possibly the addition of a fan to help keep it cool.
I’m also anxious to get my setup more stable, as I’ve been moving things around so much the setup isn’t all that great. The convergence drifts more than I’d like — and my mechanical setup is off at the moment. Always things to do..