MPC3000 Output Problem (HELP)

Hey there!

I encountered a strange problem right after replacing the backlight (some of the red liights were on for no reason, for example. the play button light which wouldn't go off. and the pad bank switch also turned on the Full Level Light.

I somehow managed to solve this problem by checking the ribbon cables were completely on. I must have accidentally knocked it out of place.

Relieved, I decided to check if everything else was OK, now it seems the right stereo out is totally ignoring main stereo volume knob.
I noticed something was wrong as soon as I tried to preview the sample, the right channel was outputting much more louder than the left.

I assigned a sample on one of the pads and it turns out and again (now with the stereo mains turned all the way down), the right channel is still playing much louder than the left.

I already tried switching the cables around, plugged in some headphones.
Same deal.

Any thoughts?

fknchino wrote:Any thoughts?

While inside your MPC you have possibly partially disconnected the cable from the Volume PCB (under the Stereo Volume knob/front panel) to the AD/DA PCB.

Check that the cable is connected/seated properly, both on the Volume PCB (connector W701) and the AD/DA PCB (connector P103).

If you removed the cable, maybe you didn't put the connector back on the pins correctly.

Yep I see the problem now! one of the tiny red cable, more specifically the one sitting farthest away has been disconnected somehow. Now to put it back in........

Have a look at the other pins in the connector/plug, try to put it back in the same way.

It might have a little tab sticking out the side of the pin on the end of the wire, that has to go in the same orientation as it is on the other pins, so it locks into the connector/plug housing.

SimonInAustralia wrote:Have a look at the other pins in the connector/plug, try to put it back in the same way.

It might have a little tab sticking out the side of the pin on the end of the wire, that has to go in the same orientation as it is on the other pins, so it locks into the connector/plug housing.

The problem is that the wire has been yanked off the tab/pin, just wire showing.
Btw cheers for the help Simon.

No probs, good luck with it.

SimonInAustralia wrote:No probs, good luck with it.

No luck, the tiny red cable wont seem to stay in. Unfortunately I don't have a solder. I might need to replace it with an entire new cable. The cable though seems very stuck on the volume pcb, would it be safe to take it out with some pliers?
Not very experienced at these things unfortunately.
Where would I look if I were to get a replacement?

I don't think I would use pliers to remove it, as it might not be a removable connector, it might be permanently connected at that end, I have not had a close look at it.

fknchino wrote:

SimonInAustralia wrote:No probs, good luck with it.

No luck, the tiny red cable wont seem to stay in. Unfortunately I don't have a solder. I might need to replace it with an entire new cable. The cable though seems very stuck on the volume pcb, would it be safe to take it out with some pliers?
Not very experienced at these things unfortunately.
Where would I look if I were to get a replacement?

if you have enough slack, you could twist the wires back together and cover with electrical tape. Or else simply get some wire - desolder the ends and re-solder.

Or use outputs 1-8 in the meantime.

Shostakovich wrote:

fknchino wrote:

SimonInAustralia wrote:No probs, good luck with it.

No luck, the tiny red cable wont seem to stay in. Unfortunately I don't have a solder. I might need to replace it with an entire new cable. The cable though seems very stuck on the volume pcb, would it be safe to take it out with some pliers?
Not very experienced at these things unfortunately.
Where would I look if I were to get a replacement?

if you have enough slack, you could twist the wires back together and cover with electrical tape. Or else simply get some wire - desolder the ends and re-solder.

Or use outputs 1-8 in the meantime.

Don't quite understand. the wire has pretty much ripped off from the connector itself and theres a tiny bit showing. The least I can do which I've already tried was stuffing it back into the hole where it belongs and that didn't seem to work.

I think that the white connector on the end of the cable is not a removable plug, but possibly a solder in PCB header/connector that can not be removed.

This means that you are probably going to have to desolder the connector to repair/replace it.

I suppose that some possible solutions might be...

- extend/solder the loose wire onto the opposite side of the Volume PCB, joining it onto the same pin that it came off of, but on the other side of the PCB where the header pins are sticking through and you have the existing soldered connection.

- see if you can cut the end of the header/connector at that one pin, remove the single pin section of header/connector, leaving the existing pin exposed, solder the loose wire onto the exposed pin.

- desolder just that one pin, cut that end of the white plastic header off, solder the loose wire directly to the pcb in place of the removed header section/pin.

- desolder the whole header and replace with a new one onto the same cable, or a with a new cable (with or without replacement header/connector) that has the correct connector at the other end to join onto the AD/DA PCB.

- source a replacement Volume PCB with the two (four) cables already connected, and swap yours out for the replacement.


The soldering/desoldering solutions would require some equipment/skills, if you don't have these, maybe you could remove the Volume PCB and attached cables, and take it to someone with the equipment/skills to fix for you.

Or take the whole thing to someone and pay them to deal with it.


A temporary workaround might be to remove the Stereo Volume cable from the AD/DA PCB, at the other end of the cable, so that both left and right volumes are running at full and equal level, or just run the Stereo Volume at full, until you sort out a proper fix.