Sampler limitation on MPC-2000; It doesn’t play FM bass well

JVC wrote:... Low frequency sound on MPC-2000 is OK to me, but if the sample has high and low-end at same time, 2000 don't would produce distorted sound.

I meant to say "... 2000 would produce distorted sound."

My first MPC2000 classic came with the sinewave sub bass tone........That was bass nirvana !!!!!! Ill sample a latley bass on the 2500 and see.

dryad-66 wrote:My first MPC2000 classic came with the sinewave sub bass tone........That was bass nirvana !!!!!! Ill sample a latley bass on the 2500 and see.

I've made sub-base sinewave WAV files for my XL long ago. XL can play the samples well. Actually, when it is played with XL, it adds a slight bit of buzzy sound to it, which sounds kinda nice...

How are you recording the MPC and what have you got it plugged into when you are recording it?

Whilst neither vintage MPC is the pinnacle of audio quality something sounds wrong there to me. You can hear slight crackling as the note fades away which shouldn't be there. I have a small old Spirit mixer I use as a sub mixer and the pots on it are a bit knackered on a few channels, that has the same effect on anything I plug in on those channels.

I will replicate this test for you using my XL when I get some time later today. And I'll also sample my TX through the analogue ins although my TX is way noisier than your sample from memory! Let alone the DX-100

When I had the MPC-60 here I also had some big speakers that could reproduce down to 30hz, if I'd sample a note from my SH-101 into the 60 it would totally rob the bottom end unless you dropped it down (pitched it down more). I guess that would be harder to hear with my current setup but was funny to hear.

Also to add re smearing on the 2000/XL, this is mostly true when pitching samples up or down as they used the simplest/cheapest sample interpolation algorithms on the 3k series compared to the 1k to make them more affordable.

To be honest when playing the sample back without pitching it up or down, so as is from memory it should sound just like the source.

Also re glitching have you tried re-seating your ram/cleaning the pins with IPA/Alcohol (Not beer )
I had this issue along with some random crashing and doing that fixed those issues

I recorded 2000XL and MacBook Air with Quattro USB (which is connected my old MacBook) directly from line out.
I simply played the exactly the same WAV files from MacBook Air and XL, and recorded it.
My 2000XL's pot and RAMs are fine. My XL hasn't crashed even once.
We all know that 2000XL sounds darker than modarn DAC, so the result didn't surprise me.
You should use my sample (latelyC3.wav) and test it.

The 2000XL only sounds darker when you pitch samples away from the root note. It's converters are not lo-fi but pretty well regarded for their time Burr Brown's, actually the exact same ones as in the MPC-3000! If you look at the schematics they are almost identical in their output stages.

From input to output the audio is almost identical, there is something wrong with your MPC as I will prove.
It's also chomping away your top end

Here is what my MPC sounds like: https://we.tl/NuiNQ8abXe

And here are some spectral diagrams that back this up:

So here is your original file:


Here is my MPC playing back your file which I transferred across:


And here is your MPC, clearly cutting upper frequencies at anything above 16k!

Wow!! How can that happen? Did you test the output from my MacBook Pro as well?

Hi vinyl_junkie,
Come to think of it, it the 16K cut off might be caused by Quattro. But, I'm more concerned about the trailing noise that happens when the FM bass sample is triggered with my MPC. If the MacBook Pro sample also shows the 16K cut off, then we can safely say that Quattro USB is the bottle neck (which would be an another discovery for me.)
For the sound quality of MPC2000, I even noticed with MPC-2000 classic. They didn't sound same as, say, CD players. I always thought that it is that way with MPC-2000 series. Of course I'm talking about root pitch sample.

Anyway, thank for running test. It is quite likely that something is not well with my MPC.

I didn't originally, but here you go.
Looks ok.


Apparently the MPC-2000 classic has a bug in the filter, so the filter is always at 1% resonance. It's never completely off.
But this shouldn't affect the top end this much, I'm not sure what's causing that.

vinyl_junkie_1620 wrote:I didn't originally, but here you go.
Looks ok.

Apparently the MPC-2000 classic has a bug in the filter, so the filter is always at 1% resonance. It's never completely off.
But this shouldn't affect the top end this much, I'm not sure what's causing that.

Umm, so it really is my MPC-2000XL, not all 2000XL suffers the same issue? (It is good to know that my Quattro USB is OK though.)
I never thought that my 2000XL would have issues like that. I'm glad that I posted it. I would've never thought of it.
I've heard about the 1% resonance bug on 2000 classic, but I thought it was a myth.
But, my MPC is 2000XL (I replaced 2000 classic with XL long ago). Does XL have the same resonance bug that you mentioned?
I have a 8-out board installed on my XL (I rarely use it), I'll record the output from the 8-out.

P.S. I just checked your WAV file. You are right, I don't hear noise like my XL. Sounds very clean to me.

I'm not sure about the resonance bug, I can't confirm that but I have heard people mention it.
Do you have a analogue synth that has white noise or anything that can produce it that's not sample based? I.e. not JV-1080 as that's 32k sample rate so you'll naturally loose the top highs.

Try sampling that in the MPC and see what happens, If there was nothing wrong it should look like this on a simple spectrum analyser.

I reseated the RAMs on my XL and tested again. It is same result, didn't improve the sound.
The noise is very consistent. It always sounds the way I posted.
I also tried 8-out. The result is the same as stereo line out.

vinyl_junkie_1620 wrote:Do you have a analogue synth that has white noise or anything that can produce it that's not sample based? I.e. not JV-1080 as that's 32k sample rate so you'll naturally loose the top highs.

Try sampling that in the MPC and see what happens, If there was nothing wrong it should look like this on a simple spectrum analyser.

I purposely avoided sampling with my XL. I wanted to narrow down the root cause (could be ADC or DAC, or even both bad even).
I should try sample with XL, then export the WAV file to MacBook Air. That way, I can test ADC (and not the DAC) on my 2000XL as well.

But, I'm already convinced that where is something wrong with my XL's DAC. Since noise is on, even from 8-out, I think there is something wrong in processor level.
I don't have analog Synth (I have Kurzweil K2000 and and borrowed Micro Korg with me), but I have a white noise generator called AM radio!
But I should just get a WAV of white noise (I don't trust my XL's ADC now, I have a sound test CD, so I'll take white noise from the CD) and trigger it from my XL, record it with my Quattro.

That is very strange that the same issue is also on the 8 out board I guess as you say it goes beyond the DAC's but something more with the machine itself.

This will sound strange but have you tried other cables?