HI RON
I just picked up both of these boxes within the last two weeks the r84 only played full blast when i got it, the volume control seems to be the original, but i may swap that from the r86 as a test. i will double ck that shorting bar tonight to make sure its not on dual. you ask...<is the correct jumper installed on the "bad" pre-amp ?> by this do you meen the above mentioned shorting bar? or are you asking something else? the shorting bar is just a little rectangle 2 slot deal on both units. there is a some what local jukebox junkie that im told rebuilds thes amp units in the $100 price range, but i hat to have another chunk of $$ in vested in this unit. with moving the speaker whires on the transformer or what ever, i was able to get the volume down to a level where it can at least be played without blowing the windows outta the place..lol so if im cant figure something out on here, i may just live with it as is, unless some one on here can hook me up
withe a cheap working preamp board....... would the 4 football shape deals on the actual amp heatsink fins have anything to do with vol. control? just wondering
thanks again