MPC 60II Distorted samples... With hacked memory.

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MPC 60II Distorted samples... With hacked memory.

By The Grublet Thu Dec 16, 2010 2:30 am
Any of the hardcore schematic folk know what the probability that the hacked mod is causing the distortion... just got the machine the other day... already went thru the input switch (high mid low), and re-did the input pot to make sure it wasn't on that side...


everything looks good on the sample in board (whatever it is called)...

I am going to swap the input board on my good (working)60II to see if it is at all (that) board... :roll:



I can see what they did with the hack mod, and I don't SEE anything obviously wrong... but being that memory can cause this, I'm guessing that it is there....


Like I said, anything from the gurus would help... test points, stuff like that..


I am hearing audio, and at a very low volume, very low high input sensitivity... no bass and distorted...


I can see the readout on the sample screen and it responds as it should.




HELP A GUY OUT!
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Re: MPC 60II Distorted samples... With hacked memory.

By peterpiper Thu Dec 16, 2010 3:07 am
So you also got a working 60?
I would try to load a disk from that working 60 into the new 60.
theoretical it should show you if the problem is caused by the memory hack (good samples are played distorted)

peace

I thought about it: If the good samples from the working 60 are distorted in the new 60 it could also be the output stage :)
So I would also try to save a sample sampled with the new 60 and load it in the working 60.
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Re: MPC 60II Distorted samples... With hacked memory.

By The Grublet Thu Dec 16, 2010 3:30 am
I am going to see if I can cross OS's on the floppy format... good call though..


I guess if the good 60 sample is loaded into the bad 60 and it plays normal, then I know the hack works...


I mean it does read all 26 seconds of sampling time.... so this could be a working hack, and I should be able to repair the sample board....


If it does not play in the broken 60, and comes out distorted, I will know it is probably the hack...



I don't think it is output stage... i checked the individual ports, the main outs and the headphone jack, and all 3 seem ok, but who knows...


keep em coming, and thanks for the idea.
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Re: MPC 60II Distorted samples... With hacked memory.

By The Grublet Thu Dec 16, 2010 3:45 am
CORRECTOMONDO...


Love it when people school me on dumb shit...


so it plays normally on the shitty one with the sample problem... memory should be fine.




WHAT NOW??




I NEED HUNTER OR ROHAN to take a walk thru this with me.

or you got more game peter :D ?
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Re: MPC 60II Distorted samples... With hacked memory.

By The Grublet Thu Dec 16, 2010 5:34 am
OK... so it was neither the sample board nor the memory....


I swapped out the 2 sample boards... and the one from the bad one works in the good one (and I am leaving it in because I already cleaned out the high mid low switch and re soldered some ish.




WAAAAAAAAAA?HHHHYHYYYHYYH???




ill keep swapping boards



FML
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Re: MPC 60II Distorted samples... With hacked memory.

By mr_debauch Thu Dec 16, 2010 6:02 am
okay so... some stuff plays fine (ie: stuff you sampled into the other machine and loaded in the hacked one) and some stuff plays distorted ( ie: stuff you recorded into the input of the hacked machine)

first thing I suggest is resetting the system to the defaults.... maybe a field is set that is causing a problem...
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Re: MPC 60II Distorted samples... With hacked memory.

By The Grublet Thu Dec 16, 2010 7:13 am
what is the 3.1 reset procedure?


I have come to the following conclusion:


both sample and output boards on both are ok...


both headphone jacks and volume knobs are working (but scratchy)

the good main board is all g, both floppys are g, and as of now it sits like this:






expanded mem board -----> good machine

non expanded board -----> bad machine

(swapped em)


Marion ------> good machine (from bad machine)




Maybe a reset is an order?


couldn't tell ya at this point.


heeeelllppppp :lol:

Re: MPC 60II Distorted samples... With hacked memory.

By MPCHunter Fri Dec 17, 2010 5:22 pm
Did you purchase the 3.10 upgrade directly from Roger Linn or is a bootleg copy from another machine? If it is a bootleg copy, it may have some bad bits floating around in the chips.

skylab001 was messing around with this issue back in this post and thought it could be due to faulty voice ROMS.

Have you changed all the electrolytic capacitors in the machine? Due to the age of the machine, I would assume most of these are past their useful life.
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Re: MPC 60II Distorted samples... With hacked memory.

By The Grublet Fri Dec 17, 2010 9:47 pm
Have you changed all the electrolytic capacitors in the machine?


Thanks hunter... figured you or rohan had some diggs....


NO, could you link a pic of wtf those look like? :lol:



Here is my diagnosis:


The good one now has:

clean case, marion, expanded (hacked) board, and the better of the two sample boards...

It sounds good, has a good tone, etc... so i'm happy with this one... (pretty ecstatic actually with this one for undisclosable reasons as of yet!)...

because now with 26.2 seconds and scsi dumpability, not to mention the very soon addition of a card reader or floppy-->Ide card reader (instead of chaining the external port like i did with my 3k)... PRETTY PUMPED


The one that is ugly, previously described as "broken"... has the standard sample time, no longer has marion...

But to me... this one still sounds dirtier for some reason... ??? After doing a parameters reset to all of the functions, it did even out the input gain level.... I guess I never really took mental note of the input volume number on the sample screen (maybe it was at 99?)


Im going to do a simple test of the same sample in both to verify if i am just crazy, or if one sounds worse.



so replacing those things you mentioned is always a good call after a certain number of years? even in the 3k as well?
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Re: MPC 60II Distorted samples... With hacked memory.

By The Grublet Fri Dec 17, 2010 10:01 pm
all the goldish yellow ones? or the weird blue ones as well?


and im assuming not the big ones on the power supply?



also, what are the things that look like this on the output channels?

Image
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Re: MPC 60II Distorted samples... With hacked memory.

By mr_debauch Fri Dec 17, 2010 10:10 pm
The Grublet wrote:
Have you changed all the electrolytic capacitors in the machine?


Thanks hunter... figured you or rohan had some diggs....


NO, could you link a pic of wtf those look like? :lol:



Here is my diagnosis:


The good one now has:

clean case, marion, expanded (hacked) board, and the better of the two sample boards...

It sounds good, has a good tone, etc... so i'm happy with this one... (pretty ecstatic actually with this one for undisclosable reasons as of yet!)...

because now with 26.2 seconds and scsi dumpability, not to mention the very soon addition of a card reader or floppy-->Ide card reader (instead of chaining the external port like i did with my 3k)... PRETTY PUMPED


The one that is ugly, previously described as "broken"... has the standard sample time, no longer has marion...

But to me... this one still sounds dirtier for some reason... ??? After doing a parameters reset to all of the functions, it did even out the input gain level.... I guess I never really took mental note of the input volume number on the sample screen (maybe it was at 99?)


Im going to do a simple test of the same sample in both to verify if i am just crazy, or if one sounds worse.



so replacing those things you mentioned is always a good call after a certain number of years? even in the 3k as well?


yeah that volume control had me the first time around too haha... the damn gain switch on the back in decent on medium on mine or else you wind up with that volume down at some stupid low level and increasing it one point goes too far some times... though the upside is if you are tryng to over drive it you easily can.
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Re: MPC 60II Distorted samples... With hacked memory.

By The Grublet Fri Dec 17, 2010 10:19 pm
:D

It was actually pretty easy to detach the hi/mid/low switch to disassemble and clean...


But yeah, I think that for whatever reason (maybe just physically plugging and unplugging all the ribbons and power cables on the machine may have fixed something??) its way better than before...

in combination with the setting sample sens to 50... but im telling you, the sample quality before (very quiet mind you) was so distorted it was unrecognizable and unusable by anyones standards... so at least i have 2 working machines.... but Ill test them tonight with a snare or something to see if the ugly one is still dirtier.

(they usually are) :D
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Re: MPC 60II Distorted samples... With hacked memory.

By The Grublet Fri Dec 17, 2010 11:10 pm
SOUNDS GOOD NOW.... WHO KNOWS.
:shock:
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Re: MPC 60II Distorted samples... With hacked memory.

By mr_debauch Sat Dec 18, 2010 3:07 am
well maybe some cable re-seating, and part dusting did the trick. these are old pieces of electronics. things were odd back then... you have to think, that mpc is from an era where you would smack electronics when they didn't work right and that would fix the problem. remember hitting the top of the tv?
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Re: MPC 60II Distorted samples... With hacked memory.

By The Grublet Sat Dec 18, 2010 6:52 am
I use the "drop test" method on a regular basis.... I did clean some circuit boards and whatnot... but its money now!
:twisted: :twisted: :twisted:
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