MPC1000 audio out issue

Hello maybe can you help me with this issue with my MPC1000 working on JJOS2XL.
Looks to be a hardware issue: absolutely no audio output is working on both R-L output and headphone. Only output 1-2-3-4 are working properly. Analog input also working properly (visual feedback) but I can not monitor the sound when played. I tried to switch on the free OS, same issue. I open the MPC to check the visual aspect of the audio board component and so not see any visual issue (capacitors looks still good!).

Anyone would know what component could be tested and or changed to avoid buying a new audio board?

I am able to sold with classic standard tools but I am not so skilled to diagnostic the origin of the issue. Thanks for your help !

Do you get any signal out of the headphones? Might be a good idea to check just to check if it's a hardware or software issue.
I'm assuming all your samples are set to the correct output channel on the last page of the programme menu, the default setting is always TRK, which always routes through the main L/R outs anyway, but I always change them to ST just out of habit as that enables the FX sends.
Most likely an issue with the physical outputs on the back, old crapped out wiring or solder - but good idea to check the headphones too just to be sure!
Good luck!

Hello Moot, thank you for your feedback and sorry for the late reply.
I have no signal on the headphone too.
I have indeed set every sample to every output possible (1 to 4 and stereo output+headphone), it is only working on 1 to 4 output.
I have not seen any physical damage on any capacitor or other physical component .

Oh! That may be a whole other issue in that case, the audio outputs are likely fine - my guess is it has to be something on the main PCB, as the chances of the main L&R outputs AND the headphones out both crapping out simultaneously are very low..
I get out of my depth rather fast with electronic stuff, personally I'd bring it to a qualified electronics technician & see if they can isolate the faulty component.

Thank you Moot for your investigation, indeed that looks quiet difficult to solve by myself. Finger crossed to find someone with the exact same « symptoms » that could highlight the faulty component. Cheers

Service Manual http://www.synfo.nl/servicemanuals/Akai ... MANUAL.pdf

Quick check. When you go to Mode, Other, to Master Level, make sure it is on 0dB. If you turned it all the way up to -42dB then you might not be able to hear anything out of the headphone out and stereo main outs. That would be easy software fix.

On page 8 of the service manual, you can enter TEST mode and test each function of the MPC 1000. This includes A/D signal tests. There's an AUDIO test in the F3 portion.

The L4033A501B AD/DA BLK Board has the main outs and a jumper cable that leadsd up to the front headphone L/R jack. This is the analog/digital conversion board. So you can start here and try to trace the audio signal back until you find it. You have to do this while the mpc 1000 is on and playing sound, so it is a dangerous procedure. Well, you have 12volts and 5 volts DC on that board. Maybe enough to sting ya. Just be careful probing around with multimeter, lots of light, concentration.

Another suspect board could be L4033A502A OPE-R block. The LVOUT and RVOUT. Also check for good grounds.

I have not heard any cases of outputs dying on people. The fact that three analog audio out jacks all died on you at once means that it is likely a software issue or the audio path feeding all three outputs is damaged somehow with a bad component failing to pass the audio signal through.



I would also reach out to MPCstuff and ask to speak with a tech regarding audio out problems. First ask if they've heard of a similar problem that you describe. If they can help you identify the suspect board requiring replacement, then you can return the favor by buying the part from them. They may help you in order to get a sale. MPC stuff sells the ADDA PCB board for 225.50 You might be able to get a discount on black Friday next week if that is the part you require. https://www.mpcstuff.com/akai-mpc-1000- ... pcb-board/ There's lots of capacitors on this board that i suppose could fail, although i have not heard any other cases of this being a problem with akai mpc1000s.

I'm hoping you just need to turn your Master Level to 0dB and that solves everything.

Spoiler: Problem solved !!

Thanks a lot Sense-A for this big analysis.
You actually pointed the faulty part that was the jumper cable that I considered then to check :
I dismantled the rear AND the front cover: I could observe that the jumper cable was badly inserted…
It probably happened some years ago when I changed some plastique push button by the front cover.

I am very happy that there is nothing more too serious , so thanks a lot again to you both who helped me

Glad you found the problem!

All working OK again now?