Post your views and questions about the Akai MPC2500
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By richie Thu Jan 24, 2019 11:04 pm
It's not clearly listed in the service manual.

I remember it being a RK14K12-D series, so you can also order RK14K1230D0R while you are at it in case the one you chose did not work out for you.
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By richie Fri Jan 25, 2019 8:31 pm
That's because Akai didn't list the part name based on the real naming but based on their naming convention.
By misterfade Fri Jan 25, 2019 10:26 pm
richie wrote:That's because Akai didn't list the part name based on the real naming but based on their naming convention.

Ah, ok got it. But is the RK14K1230D0R the same for both rec/main? They seem to be different.
By Wreckon1 Mon Mar 22, 2021 5:37 am
Hey guys,
Were you able to figure out the ALPS model number of the replacement record/volume pots? Do you know if they are different or if they are the same?

Thanks
By misterfade Mon Mar 22, 2021 12:54 pm
Wreckon1 wrote:Hey guys,
Were you able to figure out the ALPS model number of the replacement record/volume pots? Do you know if they are different or if they are the same?

Thanks

Mine aren't too bad now so I didn't get around to replacing them yet but I would like to eventually.

I still don't know if that part is the same or not because looking at the MPC Stuff site it says they're different. I might end up just getting it from their site to be safe even though the price is high.

https://www.mpcstuff.com/mpc-2500-volum ... y-encoder/
By okto Tue May 11, 2021 3:44 am
I have more information than anyone EVER wanted about this. It's compicated and not straightforward, so strap in. :P
misterfade wrote:I can't seem to find "rd14k12d" anywhere.

So, Akai sort of took the Alps (now Alps Alpine) part number and mixed it up to make the Akai part number.
The Alps RK14K is a series of potentiometers, and the Akai service manual gives us clues to which individual ones they are.
rec: vr rotary RD14K12D L20 C203x2

"RD14K12" is the series,
"D" indicates a vertical pot for volume
"L20" corresponds neatly with 20mm, one of the available shaft lengths for an RK14K-series pot,
"C" indicates an exponential or "audio" resistance taper, decreasing clockwise,
"203" is the code for a 20kOhm resistor (20 followed by 3 zeros),
"x2" because it is a stereo pot.
main: vr rotary RD14K12D L20 3B103x2

"3B" indicates a linear resistance taper increasing clockwise with increased resolution at the low and high ends,
"103" indicates 10kOhm.

Assuming my decoding of Akai's gibberish part number is correct, current Alps part numbers for these (according to the attached data sheet this information comes from) are as follows:
Record level: RK14K12D0-F20-C0-C203
Main out & Q-link: RK14K12D0-F20-C0-V103

Now here's where it gets trickier: those are ordering codes when you're ordering parts direct from Alps by the thousands. In practice, there are part numbers for common configurations that they produce regular runs of.
For the main out and Q-link pots, that part number is...doesn't exist.
For the record level pot, that part number is...doesn't exist.

That unfortunately is all I have for the moment. I'm going to poke around and see if I can find anything that will suit, but basically Akai custom-ordered some pots from Alps and they don't make them anymore, unless you want to buy a thousand of them.
By okto Tue May 11, 2021 4:22 am
There is an option for the Q-link and main out pots which has a straight linear resistance taper, but the shaft is 5mm too long, so it will have to be trimmed so the knob can fit flush: RK14K1230A0X
I can't comment on whether the special resistance taper the original part uses is critical or not, I have a couple on order and I'll report back once I get them installed.
The RK14K1230D0R part number that has been shared in a couple threads appears to be the same part number with a threaded bushing, but I can't decipher the "0R" at the end of the part number and Mouser does not indicate what resistance taper it is or what the pinout is. They're out of stock til mid-June, but I have those parts backordered as well so I can hopefully give a Real Definite Answer about which pots are correct.

Unfortunately it still looks like the reverse-taper the record gain pot needs is not available except by special order.