Exchange tips and tricks for the Akai MPC4000
By cortoni Tue Dec 03, 2013 11:46 am
Hello,
This is my first post here. Since January, date at which I bought the MPC, I've always been able to solve my newbie-issues, many thanks to the forum :) But this time I can't find a 'simple' solution to my problem! Let's describe it:

I perform live acts on my MPC4000, some techno-music style. As you probably know, there's a huge need for low and high pass filters during DJ-sets/live-sets, for example to make transitions between tracks.

As I am short of Q-links, I wonder how to replicate the Traktor DJ-software's filter with only one Q-link.
It behaves as follows: one single potentiometer controls both LP and HP filters. When you turn this pot from minimum value to center, you increase the LP cutoff. At the center, both filters are "bypassed", you have the original sound. Then, only when you go into the second half of the pot (from center to maximum), you increase the cutoff frequency of the HP. So it's a way to have 2 distinct filters on one potentiometer.

I managed to get something working, but it is probably not optimized at all, and I hope to find a better solution.
Just trying to do it on one drum program for now. Here is what I did:

- Select a triple filter (assigned to all pads)
- Set the first filter to a LP 2-pole and the second to a HP 2-pole
- Set them both with an initial frequency of 0 (so the sound is cut off by the low-pass for now)
- In Q-link setup, let's send a CC (CC79 for example) from 0 to 127 with Q-link 1

Then I go in the modulation matrix:
- CC79 --> TF cutoff 1 ==> 100
- CC79 --> TF cutoff 1 ==> 100
It makes the LP's cutoff increase twice faster than the CC79. So the maximum value is reached when the Q-link is in central position, going in the second half doesn't do anything more as the filter is already completely open.

For the hi-pass it's more complicated as the initial cutoff cannot be negative, and this is where I don't like my solution.
I have to set another CC (CC80) to offset the cutoff in the mod matrix.
- CC80 --> TF cutoff 2 ==> -100
- CC79 --> TF cutoff 2 ==> 100
- CC79 --> TF cutoff 2 ==> 100
This ensures me that the first half of Q-link turn increases the HP cutoff from "-100" (=0) to 0. But the problem is I have to set CC80 manually in the sequencer, I can't have it tightly attached to a Multi/Program.

Is there a way for me to properly offset the high-pass cut-off? or maybe a completely different method to have this function working?

Feel free to tell me if I'm not clear. Thanks in advance!
By dustymaestro Wed Dec 04, 2013 5:47 pm
I don't think the features your asking about are on the unit. A work around maybe a q link sequence. You could also try having that effect pre recorded. What's on the other Q link knobs and faders? Why can't you have cc messages attached to a multi/program?
By cortoni Wed Dec 04, 2013 10:47 pm
Hi, thanks for your answers.

@ Dustymaestro
Indeed, Q-link sequence could be interesting to set this "offset CC" without programming it in the sequencer's track. But I would have to use 2 Q-links for that, right?
The other five Q-links are busy with: pitch, FX (flanger, reverb & pitch shifter), and amplitude envelope decay. And there is really none of them I would like to give up.

@ Ntalec
No it's pretty the opposite, I've actually left Traktor & DJ stuff, with whom I felt I had not enough control over my own tracks. Plus, MPC 4000 is perfect to control all the hardware (synthesizers, guitar pedal, effects), as Traktor merely can send a MIDI clock :)
I'm happy with my current setup, just trying to get the best from my 4000. In fact, it's just about saving one Q-link. From this point of view, your idea of a controller is good, I could just buy a MIDI controller (Behringer BCF or BCR) plugged in the MPC to expand the possibilities of live handling. This way it would be easy to control all the CC's. I'll give a look if I can't get my idea working :)

Back to the subject, instead of a CC controlled by the sequencer, I also tried to use the auxiliary envelope set like this: no attack, max sustain, max release. Then in the mod matrix:
AUX ENV --> TF Cutoff2 (Hi-pass) ==> -100
So that anytime a note is hit, the HP cutoff has an offset value of -100 (=0). Then with the Q-link controlling HP cutoff from 0 to +200, it could achieve what I want.
But in practice, it isn't working and I can't understand why.
Anyway, I keep searching for an answer, any help on how to achieve that is welcome, even if it seems an odd idea.
Thanks!
User avatar
By Coz Thu Dec 05, 2013 10:28 am
cortoni wrote:Anyway, I keep searching for an answer, any help on how to achieve that is welcome, even if it seems an odd idea.



This seems like a lot of faffing around for what should be a relatively simple task. If you've run out of Q-Links you could look at a separate controller and map more controls.

Alternatively (and this is what I'd do), you could buy a hardware analogue filter and patch it into the mixer you perform with. You could then use the 4K's low pass globally and the hardware filter for high/band pass. 8)
By cortoni Thu Dec 05, 2013 1:10 pm
Coz wrote: This seems like a lot of faffing around for what should be a relatively simple task. If you've run out of Q-Links you could look at a separate controller and map more controls.

Yes, that's definitely because I use many machines ; and in a live context, space is a big concern, that's why I would like to avoid a controller. Or maybe a small one, some kind of Akai LPD8/Korg Nanokontrol with MIDI OUT.
But I'm totally fond of your second idea! (that's totally how I am, wheeling and dealing with modulations, CC, etc, and not seeing obvious solutions :Sigh: ) Plus, it would allow me to keep using the MPC 6-poles filter which sound awesome instead of the 2-poles of the MPC triple filter.
I'll look for a rack multi-mode filter, analogue or digital (I've 2U left in my rack case, so space is not a problem here). Let me know if you have some recommendations about that. Many thanks!
User avatar
By Coz Thu Dec 05, 2013 1:36 pm
The MFC 42 has always served me very well for filtering duties. A few years ago I had it patched into the effects loop of a Rane mixer and the 4K sounded great through it. The simple wet/dry effects control of a DJ mixer seem to work well in that situation.

I've got it patched into a Mackie Onyx mixer these days so it's convenient to filter sounds from anywhere and run them to the 4K or into Cubase.
By cortoni Thu Dec 12, 2013 1:10 am
Finally bought an Alesis Akira (1U rack) as an insert for my mixing desk's main output, the multi-mode filter sounds pretty nice, and there are some other useful effects (bitcrusher, vowel filter, vocoder). The big advantage is the ability to completely bypass the unit with a footswitch, which allows me to have everything clean after messing with the filters.
Free Q-links again, yeah! 8)
Many thanks!
By rogue scrunt Thu Dec 12, 2013 8:07 am
cortoni wrote:Finally bought an Alesis Akira (1U rack) as an insert for my mixing desk's main output, the multi-mode filter sounds pretty nice, and there are some other useful effects (bitcrusher, vowel filter, vocoder). The big advantage is the ability to completely bypass the unit with a footswitch, which allows me to have everything clean after messing with the filters.
Free Q-links again, yeah! 8)
Many thanks!



good score, the Akira is hard to find