We could sync the props/engines on the DC-6. Either engine #2 or #3 could be selected for the others to slave to.
What sort of sync was it , RPM or actual magneto firing.
This goes back to my original question at start of this thread asking for an explanation to the difference in sound between a connie, L 1049 say, and the Douglases. Someone commented before that the PRT probably had a lot to do with the difference.
Regarding syncing on the DC6 was there a significant difference in sound when in sync or just less vibration. Although the criteria was probably to obtain equal thrust (power) from all engines.