Exchange tips and tricks for the Akai MPC4000
By ST3 Wed Nov 11, 2015 3:07 am
Hi All,

The LCD screen on my MPC 4000 went out. The screen lights up, but nothing is displayed. Aside from the LCD screen, the unit appears to be working as I can connect via Aksys to see the hard drive, load programs, play the pads and start and stop sequences. I see that there are a few websites that sell replacement screens for the MPC 4000, but to be honest they are overpriced for a low resolution LCD screen.

I am sure this path has been crossed before, but I not having the best of luck finding an LCD screen for the part number listed in the service manual. I have found a couple sites, but they want you to specify the LCD's resolution and then go from there. I called Akai, but they directed me to one of the MPC parts sites that I am trying to avoid.

Does anyone know of an OEM supplier with a part number that sells the screens? Hopefully for less than the sites that market the LCD screens as MPC 4000 replacement screens.

Thanks
By richie Wed Nov 11, 2015 10:36 am
Buy a Akai S5000 or 6000 and you can use that screen in the 4000.

EDIT: Looks like S5000/6000 is too big.
By ST3 Wed Nov 18, 2015 12:56 am
richie wrote:@MPC-Tutor I cannot 100% say that it can be done without modification.

My initial response to this thread was based on the pictures I saw in Genesis92's thread http://www.mpc-forums.com/viewtopic.php?f=2&t=175302 . I happened to have my S6000 open for another reason, noticing that it was the same screen + board as the 4000 - which likely makes sense considering the date of the 4000/S5000/S6000 production was in the same time period.


Thanks for the heads up. I found an s5000/6000 LCD screen for $59 and am going to give it a shot. That's a lot better than paying $120 to $200 for an S5000 to tear apart just for parts. I think I would cry knowing that I would be cannibalizing such an awesome sampler. :P
By ST3 Fri Nov 20, 2015 4:45 am
richie wrote:@MPC-Tutor I cannot 100% say that it can be done without modification.

My initial response to this thread was based on the pictures I saw in Genesis92's thread http://www.mpc-forums.com/viewtopic.php?f=2&t=175302 . I happened to have my S6000 open for another reason, noticing that it was the same screen + board as the 4000 - which likely makes sense considering the date of the 4000/S5000/S6000 production was in the same time period.


Update: The LCD Screen for the S5000 is a lot larger than the LCD in the MPC 4000, also the the MPC 4000 has more connections on the ribbon cable. Looks like the search continues.
By richie Fri Nov 20, 2015 8:43 am
@ST3 I do apologize for the inaccurate information I shared. I hope that you didn't already spend money over this as I would feel guilty if so.

@MPC-Tutor I'd like to modify my previous posts regarding this to reflect the mistake so no on else buys it for nothing.
By ST3 Mon Nov 23, 2015 1:53 am
MPC-Tutor wrote:The dps16 screen should fit the 4000


Awesome news. I did a google search for dps16 replacement LCD and this was one of the first links that popped up in the results;
viewtopic.php?f=2&t=168589&start=15

Not sure why that didn't come up when I was searching the site?

Anyway, I am now on the hunt for a dps16 screen... or a used dps16.

Thanks,
ST3
By Sense-A Tue Apr 16, 2019 1:59 pm
It seems kind of ridiculous that so many Akai MPC 4000's have screen issues yet there's no affordable supply of replacement LCD's.

Here are some specs that may help myself and others track down viable, affordable options.

First, from the Akai MPC 4000 service manual available here: https://www.vintageshifi.com/repertoire ... Manual.pdf

Image

Part number is EM-812761J IND LCD
Description is IND LCD G321EV5R001

Importantly, it is a 320x240 lcd display module

With this information, we should be able to track down aftermarket LCD's and begin restoring MPC 4000's or even find an upgrade to the very flawed LCD's it shipped with. Problems range from bad backlights to horizontal lines going across the screen. Often the problems are from bad ribbon cables or degrading contact points.
By Sense-A Mon May 13, 2019 4:12 pm
Wow. Is this forum dead or what? I know there's lots of MPC 4000's out there with bad displays. Half the ones on eBay have lines going through the displays. So I expected more people to be interested in this thread.

So I pulled the LCD out of my MPC-4000. Here is the information that is written on the board, which is far more helpful than what the manual provided: Sii G321E TW2294V-0 REV.D

There's lots of Sii G321E TW2294V-0 LCD display modules available on the market. That's what you need to look for. Heck, did you know that the Emerson CSI 2120 uses the same LCD as the MPC 4000, only with a touchscreen overlay that can be peeled off? I got one used for $40. I might post pictures of how I made it work.

Here is some more information you might need to know.

Board Height 96 mm
Board Width 150 mm
Screen Height 80 mm
Screen Width 103 mm
Diagonal Screen 5.125 in
Diagonal Screen 130 mm
LCD Model Sii G321E TW2294V-0 REV.D

A guy on Reverb/eBay is selling an LED backlit model but mentions that he had to modify it some to get it to fit and align with the window in the MPC 4000. He and MPCstuff sell replacement LCD's for $229+ But if you look up the information I've provided you, you can get replacements shipped to you for less than $50.

I'm currently doing some research to convert the LCD signal data to a VGA output. I think I can achieve it with less than $50 worth of parts. This way I can have the screen on a monitor, however, it will still be low 320x240 resolution. In other words, what the MPC 3000 does with its video output. When it comes to these sort of things, arduino forums are often much help since people are doing all sorts of tricks and conversions with arduino boards.
By CharlesRandolph Mon May 13, 2019 11:42 pm
This would be interesting to see. I've Stockpiled lots of MPC 4000 screens so I wouldn't have this issues. One of my main things would be finding someone who could write a Windows 10 Driver for the MPC 4000.

Would you have any leads on that?
User avatar
By JUKE 179r Tue May 14, 2019 9:20 am
@Sense-A... thanks for the research and info. Please keep it coming.
My screen looks like it's bleeding as in having different colors. I was looking at the LED screens for the 4000 on ebay but they are £150/$195.
By Sense-A Tue May 14, 2019 2:30 pm
As an alternative or else backup to the poor quality displays in the MPC 4000, it would be nice to have a VGA output to hook up an external monitor in similar fashion to the add-on vga output that is available for the MPC 3000. Don't expect anything as pretty as AK.SYS Most likely, the best we will be able to get is a mirror view of the low resolution 320*240 pixel dot matrix display on our LCD. See MPC 3000 vga output example here: viewtopic.php?f=4&t=113189

Image

Such an idea is not new. It was desired and discussed in this thread for an MPC 2000: viewtopic.php?f=1&t=141203

It is not easy because the way the LCD data is delivered to the MPC 4000 LCD is called LVDS, or Low-voltage differential signaling. This is different than the RGB (red green blue) signaling that is sent through VGA. You may have to open the following image in a separate window to view it properly:

Image

Here is what we have available on the MPC 4000:

1 FLM  First Line Mark / Shift Direction Select
2 M Alternation Control Signal
3 CL1 LP, data latch (row) / Display Data I/P Clock
4 CL1 CP, data shift (column) / Display Data I/P Clock
5 DISPOFF Controls Display off, 0: off, 1: on
6 D0 Data Pin
7 D1 Data Pin
8 D2 Data Pin
9 D3 Data Pin
10 VDD+5V Power Supply 5volts
11 VSS-GRD Ground
12 VLC-24V
13 VO Contrast Adjustment, usually uses POT that can source 0-5V
14 FGND

I could have pins 3 and 4 backwards....

I spent a few hours researching this last night. I was looking for LVDS to VGA or LVDS to TLL or LVDS to CRT or LVDS to RGB.

There's actually a lot of arduino users who have developed circuit boards to adapt a HDMI or VGA input to an LVDS output, but not the other way around. They are using the LCD screens out of old broken laptops and connecting them to their arduino modules and feeding in external video from HDMI or VGA or from arduino video output. I could link you to many boards that convert the signal in this direction. It's not as easy as just matching up wires. There is heavy calculations that need to take place to convert the clocking/timing. We need a solution that converts in the opposite direction, which is harder to find.

Converting VGA to LVDS is discussed here: https://forum.arduino.cc/index.php?topic=102181.0

Some information about how VGA works, importantly ...clock cycles: https://people.ece.cornell.edu/land/cou ... index.html

Other online discussions about this relate to old arcade users who want to convert old LVDS outputs to drive arcade monitors. This requires a conversion from LVDS to analog RGB.

Texas Instruments actually produces and sells LVDS receiver chips which provide a parallel RGB out. One such chip is the SN75LVDS86 http://www.ti.com/product/SN75LVDS86 Could something like this work as part of a circuit board video adapter? Possibly. I'm not sure yet.

Something like this could possibly be used to split the LVDS output in the MPC 4000: http://lcdparts.net/ms544lc.aspx

I could probably get this to work with an LCD screen I put out of a laptop. But designing something similar to the MPC 3000 VGA board is going to take more research and studying.

Someone who works for Texas Instruments proposed a possible solution here: https://e2e.ti.com/support/interface/f/ ... VDS-to-VGA

"The DS90CF386 FPD LVDS Receiver could do the LVDS to RGB Data conversion followed by a video DAC like the THS8200 for the RGB Data to VGA."
By Sense-A Tue May 14, 2019 2:39 pm
It is strange that no one has produced something like this in the market. Imagine if you could take the dot matrix display out of any old 80's or 90's sampler/synth and convert it to an output monitor? It would be useful especially if you are remotely controlling multiple devices via midi and want to view the native LCD screens on a monitor near your midi controller to see what you're doing on the remote device. But its usefulness is limited and not worth the hundreds of dollars that something like the MPC 3000 VGA output commands.

Which brings me to my next question. Can anyone provide schematics or very close up high resolution pictures of the MPC 3000 vga output? We might want to start by just reverse engineering that one and then building the VGA output for the MPC 4000 and MPC 1000/2500. Imagine if JJ of JJOS could modify the operating system of the MPC 1000 or MPC2500 for use on a higher resolution external monitor? He already did it for the MPC 1000 XLCD large screen available at: https://www.mpcstuff.com/mpc-1000-xlcd- ... i-mpc1000/
By Sense-A Tue May 14, 2019 2:56 pm
Evidently, the VGA display adapter for the MPC 3000 works with the MPC 60ii. viewtopic.php?t=163962&p=1716640

If anyone can link me to the service manuals for either the MPC 3000 or MPC 60ii then I can begin exploring whether or not one of these can be adapted for the MPC 4000 or the MPC 1000/2500. I'm looking for the pinout information. Also, any information about the components on the MPC 3000 vga adapter board itself. Even a high resolution picture would be helpful in identifying parts. Thanks.