Is it normal for a Lionel Legacy SD-70Ace to have a much lower engine rpm rev volume level than a TMCC SD-70 or a Lionmaster SD-90 ??? In comparison, the sound of the Legacy is about half of the TMCC loco at max volume pot/cab-2 level. Strangely, the TowerCom/radio communication seems to be pretty much the same level on both the TMCC and Legacy locos.
I tried a jumper on the potentiometer but didn't see any difference and I have no other Legacy to compare.