Post your views and questions about the Akai MPC2500
By xparis001 Fri Apr 21, 2006 3:57 pm
Hello all,

The resolution to the popping issue has been discovered. by me :)

The random popping in the output issue happens when the USB cable is left plugged in. Some computers have poorly grounded usb connections, and this can cause random popping in the output of the 2500.

I just recorded playback of the song demo (the 4 demo sequences in order) 10 times without the usb cable plugged in - no pops.

Plugged in the usb cable, played the demo song - didnt even get through the first sequence without a pop.

not all computers have this problem it seems. My Dell does, my buddy's mac laptop doesnt. We tried it on the mac 2x with no issues. same usb cable.

This has probably been made obvious to everyone because with 1.1, we didnt have to unplug the usb cable anymore. I'll probably still leave it in, and just unplug when its time to record.

By _Stilo_ Fri Apr 21, 2006 4:44 pm
Sorry to disillusion you - but I had the pops even when no USB cable was plugged in.

It might be one reason however...I will test if I can reproduce what you described tonight.




Stilo.
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By jahrome Fri Apr 21, 2006 5:26 pm
After several months...I have still yet produced any pops....

Are you sure that your gear is grounded properly...or, if you are using digital gear/computer in your set-up, is everything sync'd to a good clock source?
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By Fist Full of Dollaz Fri Apr 21, 2006 6:34 pm
jahrome wrote:After several months...I have still yet produced any pops....

Are you sure that your gear is grounded properly...or, if you are using digital gear/computer in your set-up, is everything sync'd to a good clock source?


how do u ground an mpc?

By _Stilo_ Fri Apr 21, 2006 8:07 pm
So, I tried it again with the USB cable...not able to produce any clicks or pops whatsoever. That can't be the only cause. I once had the problem that only noise comes from the outs when playing the pads after unmounting the USB connection from the PC however, like someone mentioned some time ago.

I thought like you jahrome, before I had the problem myself quietly badly once...and since then I wasn't able to reproduce it. I really don't know if it's a certain setting or interface problem, or if it's rather just random. I use no digital gear, and when it happened there definitely was no USB cable attached.



Stilo.
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By jahrome Sat Apr 22, 2006 1:28 pm
As far as grounding...if you are just using the MPC alone, you shouldn't have much problems.

However, if you are several items in your studio connected to several power outlets, you can have some grounding issues, which will usually result in a hum versus pops and clicks. I only mentioned it as a way to troubleshoot and get to the source of the problems.

If you have grounding issues, you may have to add or remove ground lift plugs. One of the best ways is to attach all your gear to one or two regulated power conditioners.

_Stilo_, when you have/had these issues, was your MPC connected to any other devices?
Last edited by jahrome on Sat Apr 22, 2006 5:58 pm, edited 1 time in total.

By _Stilo_ Sat Apr 22, 2006 5:34 pm
jahrome wrote:_Stilo_, when you have/had these issues, was your MPC connected to any other devices?

Upon reading your post, I checked how I connected the devices that have contact to the MPC. It looks like the mixer over which I sample the turntables is actually powered from another power outlet. I also do remember having it connected to the MPC when I had the popping issue. So it might have something to do with that. I already suspected the Record Ins to have something to do with it, but couldn't provoke it to happen again yet.


Stilo.

P.S.: Please don't bother typing the underscores in my nick 8)
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By Jkizzla Tue Apr 25, 2006 8:45 am
Iv never suffered from pops but twice after transfering lots of files via usb onto the mpc, the mpc would produce a horrible crackling fuzz noise when I tryed to play the samples I had imported. At first I thought it was the samples. I took out the usb cable and record ins but still no change. but, when I rebooted my MPC the next day the samples all worked fine.
I suggest a reboot and take out usb cable before using files you have transfered.
I can't say for sure its the usb transfering that causes the fuzz but I know that both times I have brought more than 1 or 2 pgms and wavs over onto my mpc via usb the fuzz has happened.

By _Stilo_ Tue Apr 25, 2006 10:00 am
Jkizzla wrote:Iv never suffered from pops but twice after transfering lots of files via usb onto the mpc, the mpc would produce a horrible crackling fuzz noise when I tryed to play the samples I had imported.

Yes, that has been discussed here as well already, and I experienced it myself for the first time a few days ago (see 4 posts above). The only thing that helps is a reboot, but it doesn't seem to damage anything.


Stilo.
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By dablunt Wed Apr 26, 2006 9:57 am
[quote="jahrome"]After several months...I have still yet produced any pops....
quote]


dito

By thaimoney Fri Apr 28, 2006 3:56 am
i do get those pops,but refering to what fist full of dollaz said. is having an actual sync clock piece you put in a rack helpful compared to the internal clocks of the mpc and pro tools?