Volume Control on PSR 740

Please Some one tell me , why I cant control the volume on a PSR 740 from the keyboard when I connect the L and R of the back to a mixer or a PA. I need to control the volume some time. Will a foot Volume switch solve my problem.? Please help . Thanks

Girish

Yeah, unfortunatly the 740 has to be routed through an external volume pedal to control the audio outs. If you don't need the internal speakers on, you CAN use the headphone out jack to feed your amp. That will allow the volume knob to work, but you'll ONLY hear the amp. Pretty stupid, I think.

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Uncle Dave

Uncle Dave
Now, I have the internal electronics circuit of 740, and so I am able to clarify the question of rear outputs control volume:
Indeed, observing the electronics, it's clear that was intentional from Yamaha to let the internal speakers as monitores affected by the panel volume button and not the rear outputs. (For the rear outputs all we know that the foot pedal volume control that).
And so, it is very easy to change the default wiring from Yamaha. It's enough open the keyboard and move two wires from two points of the circuit, before the volume control knob, to other two points whose are the middle points of the control volume knob (this is as normaly, made by two variable resistores on the same axis).
The printed circuit board for this, is independent of the CPU, ROM(s) board, and very accessible.
However I think Yamaha is right and I have not changed the default.

Regards
Carlos Rodrigues

Jumping in late on this one ... just received both my 740 and the fc7 volume pedal. The volume pedal controls both internal and external speakers at the same time. Rather than open the 740 and rewiring it .. could you make a volume KNOB thingy and plug it into the footvolume plug and have a volume knob to control both speakers systems? What would be involved in making such a 'volume knob' .. (not very conversant in electronics .. as is probably evident)..

Hugh DeLong hugh@azstarnet.com