Chosen Solution
I have a Yamaha DGX-220 and the volume output is very low. Can I fix that, or must I refer ta specialist?
Hi, As @ruggb suggests this requires testing the circuit as the audio outputs are supplied by a single audio amplifier IC, which may be the problem It could also be the master volume potentiometer VR551 that is the problem though. Here’s the service manual for the keyboard. Go to p.8 to see the block diagram and find the Power amp IC551 and next to it is the master volume control VR551. This is just to give context as to how the audio is supplied to the speakers. There is no detailed wiring schematic for the board, only a board layout so this will have to be worked out if wanting to test the volume control. On p.29 and p.30 Test #13 it shows what equipment is needed to test the volume and what audio levels are expected. You may have to contact a reputable, professional electronics repair service (perhaps specializing in electronic piano or keyboard may be best) and ask for a quote.
just a guess, but it is likely a component failure in the audio amp circuit. Some serious troubleshooting must be done.
Laurel, you could ask your technician to replace 4 resistors at the amplifier board. 2pc 4.7k just infront od the amplifier ic, replace 100ohm. And 2pc 10k replace by 1k, under the ribbon wire.
