Xpantastic!

Hello Bakis,

The other posters have it right. You should replace the coupling caps. 
Specifically I would replace C549  on voice 5.  

This part fails often, and causes tuning fails.  BTW It must have the 50VDC 
rating or it won't work.

Actually I would change all Cx49 parts (x = voice number), because it sounds as 
if Voice 1 may have this problem also.

However, this does not address the bleedthrough problem you mention on the 
direct out of voice 5.
I have an M12 so I have no direct outs, and can't really comment on this.  

Best Luck

Karl 


________________________________
From: Bakis Sirros <synth_freak_2000@...>
To: Xpantastic group <xpantastic@yahoogroups.com>
Sent: Fri, January 27, 2012 2:30:18 PM
Subject: [xpantastic] hello everyone, Xpander problem, help is needed...

  
hi everyone,

new member here, my Name is Bakis.

recently bought an Xpander and have the following problem:

works and sounds great...  ...apart from voice 5, which, after its shipping to 
me, does not pass the auto tune test.
 
sometimes the 'PW' section of it fails, sometimes the Res section fails, 
sometimes all the sections of voice 5 fail (except the vca section of voice 5 
that never fails). 

 
even if i activate the problematic voice, after its been automatically shut off 
by the Xpander OS, it sounds a bit different from the others in filter tone and 
tuning (of course, as it cannot be tuned,) and very very low in volume. 

another weird thing i noticed: when i direct voice 5 in its 'direct' output 5, 
then, from this output, i can hear all of the xpander voices (together with 
voice 5) but very low in volume. 

all the other direct outputs work as they should, for all the other voices.
 
i performed software reset, re-sitted all ribbon cables and all of the chips in 
the voice 5 section of the xpander voiceboard without success,
i also performed all the tests for the xpander (memory, vmemory, etc...) and all 

are ok, afaik. 

plus i re-sitted chip U106 which is responsible for the panning output section 
of voice 5 (after studying the service manual).

also, i swapped both CEM3374 and CEM3372 of voice 5 with another working voice 
chips (voice 6) and still the fault appears on voice 5. so, both the CEM chips 
are Not the problem... 



and i swapped ALL of the chips of voice 5 with the chips of voice 6 and still 
the same problem appears on voice 5. 


so ALL the chips in the voice 5 section are ok for sure.


and, after hitting tuning many many times and hitting tuning while the machine 
was at various different presets, i noticed that thing:
when the machine was autotuning and it was in a preset that was very complex 
with lots of modulations and vco modulation as well, then voice 5 failed in the 
vco tuning as well, (and, at one time, vco 1 failed!). 

when the machine was autotuning, while it was in a simpler sound preset (some 
brass or synthlead...), then the voice 5 only failed in PWM and maybe Res... but 

it passed vco tuning....!! 

so maybe its a problem in another board of the machine (like the CPU) and not in 

the voice 5 board ?
 
maybe this indicates that i should re-sit the chips in the main CPU /memory 
board as well?? do you think i should take the time and re-sit all the chips in 
the CPU board? would it make sense?
 
(do you think a 'HARD Reset' may fix the problem? how do i do this?)

is there anything specific i should check? everything seems connected.... i 
cannot resit ALL the chips in all boards obviously... but maybe i should resit a 

specific chip from another section of the xpander boards....? any ideas / help?
 
i really do not want to break anything inside the Xpander (i do not want to use 
a soldering iron, after all, everything seems in place), but i can remove and 
easily re-sit a specific chip or two, if needed of course....
 
btw, the seller is very honest and he insisted that the machine worked fine (all 

6 voices) before shipping, and i believe him..

thanks for all your help in advance!

best regards,      :-)
Bakis.


Bakis Sirros - Parallel Worlds / Interconnected / Memory Geist 

[Doepfer_a100] group owner 

www. parallel - worlds - music. com 

www. facebook. com/ pages/Parallel-Worlds/192093934136476 

www. myspace. com/ parallelworldsmusic 

www. myspace. com/ interconnectedmusic 

www. myspace. com/ memorygeist www. DiN. org. uk www. musicamaximamagnetica. com 

www. vu-us. com