Making a transaxle with straight cut gears, quiet?

[Dave K]

Any thoughts on how to quiet a straight cut gearbox? simple is better (as opposed to Comanche helicopter style electronic noise cancelation, etc.)

-Dave
Everything should be designed as simple as possible, but not simpler.

 

[Rob45]

If you can hear the gearbox whine a half-mile away, I'd say there's a serious problem with the gears!
Virtually every heavy truck (Classes 6 through 8 in North America) has a gearbox using straight-cut gears throughout, and which are usually dealing with 1650 - 2050 lb-ft of torque.
While noisy, it's not the gearbox you hear when one drives by.