Maker Pro
Maker Pro

I have a Bose Wave system with no audio

Driver meaning the speaker itself? If it blew the speaker coil out you can measure for resistance on the speaker terminals, should be single-digit ohms. You can also set a multimeter to 20VAC range and measure for output to the speaker when it should be playing.

Does it seem to power up and work okay except for no audio? Typical faults might be the power supply itself but if it's powering up, probably not that (but you can still measure for DC voltage to the amp board), otherwise a common fault would be blowing the output transistor(s) which might be discreet or might be integrated into a power amp IC chip.

For those you'd have multimeter set to 20VAC and measure for signal getting to the input pin of the transistor or amp chip, measure for power 200VDC range getting to the power input. If you have both present you should be getting AC output to the speakers, unless it's an IC and has a mute circuit in effect.

If you can find a schematic or at least post detailed high resolution pictures it might help. I leave it up to you to decide whether you're capable of safely troubleshooting an open AC mains powered piece of equipment.
 
Bose Wave radio/ CD has no audio from radio, CD, earphone. Power up display working and CD is reading.
dave9 when you say power amp IC chip, is it the TDA 7376B.
I got the pin connection diagram for it and can take readings with meter
 
Last edited:
Yes that's a good place to start. Measure for DCV on the VCC pins, and ACV [audio signal, when sound should be playing], between IN1+ and IN1- (for one channel) and between IN2+ and IN2- (2nd channel).

If you have both power and signal to it, measure for AVC between OUT1+ and OUT1-, and between OUT2+ and OUT2-.
 
in1-and in1+ = 16.9v ,in2- and in2+=0v , out2+and out2- =0v, out1+
and out1-=0v and the VCC reads 16.6 on both 1 and 2
 
Last edited:
IN1+/- reading is AC or DC? If AC I suppose a gain stage prior to it could cause that, but if DC it looks like something failed prior to the amp chip and fried it.
 
Top