Judge Dredd
A-16917 DCS

Our Judge Dredd started exhibiting sound problems. The first being low volume output even at the maximum setting. After a couple months it started having loud pops and crackling through all speakers.

I've identified all the caps in the low and high pass sections of the board.

Replaced C20 and C21 (the big radials), and high pass capacitors 35, 37-45 and 49. Replaced the blown right backbox speaker.

The sound out of the backbox speakers is now very clean. Getting ready to do the caps in the low pass section.

What controls the volume output as that needs corrected as well?
img1j (resized).pngimg2 (resized).pngimg3 (resized).pngimg4 (resized).pngimg5 (resized).png

Recapped the low pass section of Judge Dredd and the sound is now very clean out of both low pass and high pass sections but overall volume output is very low. The TDA amplifiers have been replaced as well.

I also am working on the sound board for an NBA fastbreak we purchases that was missing the amplifier and heatsink from the A-20516 audio visual board. Again, I have clean sound out the both the backbox and cabinet speakers but very low volume output from the cabinet header.

Is this going to be an issue with a resistor somewhere in the stream?

Isn't U5 a sound rom on DCS a16917 boards?

Worked on this board a little more today. Toned low pass section and discovered that one of the legs on U27 did not have a good solder joint. Replaced and socketed the TL084 at U21 as well. Tested the board. Have the good volume level out of the cabinet speaker woofer but low volume output out of the backbox speakers.

Continuity tested the high pass section as well as checked the resistors.

So, only issue remaining is low volume output on the backbox speakers relative to the cabinet speakers. Swapping the backbox to the cabinet header brings good volume from the backbox speakers.

Gonna try solve the puzzle on this hacked up board now. I dont really care about salvaging the board, just solving the puzzle.

I have good sound quality but low output to the backbox speakers (cabinet speaker sounds great).

Since the same filtersig feeds both the low and highpass filters I'm struggling to figure out why the backbox (highpass) volume is so much lower than the cabinet (lowpass) volume.
pasted_image (resized).png