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Leslie 147A/B3 hum

 

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Hi - new to me Leslie 147A - connected via 6 conductor cable to my B3 console. ?

Wiring to 6 pin socket is as follows:?
Pin 1 - brown
Pin 2 - Leslie half moon?
Pin 3 - gray and other leg of Leslie half moon
Pin 4 - blue
Pin 5 - jumpered to 4
Pin 6 - black

AO-28 was recapped about 3 years ago and had no hum with Leslie 770

Sample here:

Appreciate advice and pointers to troubleshoot?

Joel
 

Joel , Always remember that the Leslie must be to the right of the organ or it will hum.
Your picture wasn't showing enough info. Try moving it as far to the right of the organ as?
possible.? ( setting in front of the keys to the right)

Jim Mc
 

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Will do and report back


On Apr 21, 2020, at 5:26 PM, Diayne McComis <diayne@...> wrote:

?Joel , Always remember that the Leslie must be to the right of the organ or it will hum.
Your picture wasn't showing enough info. Try moving it as far to the right of the organ as?
possible.? ( setting in front of the keys to the right)

Jim Mc

 

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Having just watched your Youtube video, I suspect that the volume of the hum increased as you opened the swell pedal. If so the hum is getting into the organ circuits somewhere. A likely cause, as Diayne suggested is the magnetic field from the Leslie motors interfering with the manual matching transformer at the left hand end of the organ. Leslie speakers, or indeed anything with a motor or transformer that may generate a mains frequency magnetic field need to be kept away from the left hand end of the organ.

On 22/04/2020 06:44, Joel Conover wrote:
Will do and report back


On Apr 21, 2020, at 5:26 PM, Diayne McComis <diayne@...> wrote:

?Joel , Always remember that the Leslie must be to the right of the organ or it will hum.
Your picture wasn't showing enough info. Try moving it as far to the right of the organ as?
possible.? ( setting in front of the keys to the right)

Jim Mc
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