Discussion about the Korg PolySix synthesizer

Johannes - could it be somewhere in the mixer (some bad opamp where 
the synth section comes in) ?




--- In PolySix@yahoogroups.com, "stagerhodes" <stagerhodes@...> wrote:
>
> Hi Johannes,
> 
> i will try your tips and see what happens...only one thing , the 
> distortion is more proeminent with EG Intensity to full positive 
> position (all turned right) not negative as you understood...
> thanks !!!
> 
> --- In PolySix@yahoogroups.com, Johannes Hausensteiner <johau@> 
> wrote:
> >
> > Hi Art,
> > 
> > No,the flanger does not have any influence on the synth section,
> > technically.
> > So, what  I get from your post is that there are (possibly) two
> > problems:
> > 1) some kind of distortion plus modulation; more prominent when 
the
> >     VCO is set to 16' or 8', and EG intensity is turned up
> > 2) the presets (Piano 1, Piano2, Clav) do not make any meaningful
> >     sound but only a short "blop" (or something).
> > 
> > ad 1):
> > please find out more about the circumsatnces of the distortion.
> >    (VCO-1/VCO-2/both, Saw/Square/Pulse wave, VCF cutoff, VCF 
> resonance,
> >    etc.)
> > 
> > ad 2):
> > - check the connection between KLM-317 and KLM-292.
> > - select Piano1 and turn of of the pots on KLM-317 belonging to 
> Piano1
> >    (e.g. cutoff = VR27; make a mark on the pot before to find the
> >    original setting). Listen to the sound or measure with DVM on 
> KLM-292
> >    on IC11/pin7 and check whether the voltage changes.
> > 
> > 
> > Good luck!
> > 
> > Johannes
> > 
> > 
> > 
> > stagerhodes wrote:
> > > thank you !...well, the controls are working, only it makes a 
> kind of 
> > > distortion which is more audible in the 16' and 8' octaves, it 
> > > reduces it in the 4' ( a distortion with some kind of 
> modulation ), 
> > > the bad effect will be more noticed too if one set the EG 
> Intensity 
> > > to center or full counterclockwise (negative envelope). I tried 
> to 
> > > memorize 2 patches and the programmer seems ok, the patches are 
> > > there, so i just don't know what to do next...
> > > I must say that it seems the top panel was (may be the unit 
> crashed 
> > > in the floor or something) bend in the master tune pot area, 
> after a 
> > > close look i saw one of the screws fixing the Flanger board , 
in 
> its 
> > > place with a small PCB fragment attached, and the board broke 
in 
> one 
> > > of its edges (screw area). I took out the flanger board and it 
> seems 
> > > no damage in any of the pcb traces...anyway does any 
malfunction 
> in 
> > > this board reflects in the synth section sound (with flanger 
> turned 
> > > off) ??
> > > Oh, the preset sounds are not ok, just a short beep (low 
> frequency), 
> > > the strings and brass are OK
> > > regards
> > > Art 
> > > 
> > > 
> > > --- In PolySix@yahoogroups.com, Johannes Hausensteiner <johau@> 
> > > wrote:
> > > 
> > >>The PCB looks OK; no damage due to leaked battery as in the 
> Polysix
> > >>is visible.  According to the pics (silkscreen) the battery 
which 
> is
> > >>mounted seems to be original or genuine replacement.  So I 
wuuld 
> not
> > >>suspect a threat like in the P6.  It largely depends on the 
> battery
> > >>make, which seems to be good quality in this unit. So as long 
as 
> the
> > >>battery retains sufficient voltage (more than 2.5V) I would not
> > >>worry about it.
> > >>This does not surprise me, since the Trident MK I programmer 
and 
> the
> > >>MK II programmer are completely different. MK I was designed 
> before
> > >>Polysix, MK II afterwards or the same time obviously useing the 
> same
> > >>technique in both (edit mode, etc). Amazingly they did not use a
> > >>microprocessor for the patch manager in the MK I but an all-
> hardware
> > >>type of design.
> > >>
> > >>Regarding your original problem: it may be (even likely) that 
the
> > >>battery is dead or at least discharged and all memory patches 
are 
> gone
> > >>producing no or meaningless sound. Are the knobs and switches 
> working
> > >>in "Manual" mode? How do the presets ("Piano 1", "Piano 
> 2", "Clav")
> > >>sound?
> > >>
> > >>According to the schematics there are on KLM-317 three sets of 
> pots
> > >>for the presets; you may set your favourite sound patches there.
> > >>(The Yamaha CS-60 and CS-80 had a similar kind of "Patch 
> Memory"..)
> > >>
> > >>Johannes
> > >>
> > >>
> > >>stagerhodes wrote:
> > >>
> > >>>Hi,
> > >>>just uploaded 8 photos of the board, hope they're ok now for 
you 
> to 
> > >>>try to help me.
> > >>>regards,
> > >>>Art
> > >>>
> > >>>
> > >>>--- In PolySix@yahoogroups.com, "gil_we" <gil_we@> wrote:
> > >>>
> > >>>
> > >>>>you're welcome,
> > >>>>
> > >>>>I'm interested to see how corroded is the board - if any at 
all.
> > >>>>
> > >>>>
> > >>>>--- In PolySix@yahoogroups.com, "stagerhodes" 
> <stagerhodes@y...> wrote:
> > >>>>
> > >>>>
> > >>>>>Hi Gil,
> > >>>>>well, i'm not at home right now, but the battery is from 
> Sanyo, and 
> > >>>>>the big lettering is CADNICA (nickel cadmium).
> > >>>>>I will take better pictures tonight and post them (deleting 
> the ones 
> > >>>>>there now)...well, what can i say besides thank you for your 
> > >>>>>support ...
> > >>>>>
> > >>>>>
> > >>>>>--- In PolySix@yahoogroups.com, "gil_we" <gil_we@y...> wrote:
> > >>>>>
> > >>>>>
> > >>>>>>It's very hard to see anything on those pictures... I do 
see 
> though 
> > >>>>>>that the battery was already replaced ?? looks like a 
lithium 
> battery 
> > >>>>>>what does it say on it ?
> > >>>>>>
> > >>>>>>Try to provide close up high resolution pictures of the 
> programmer
> > >>>>>>
> > >>>>>>
> > >>>>>>--- In PolySix@yahoogroups.com, "stagerhodes" 
> <stagerhodes@y...> wrote:
> > >>>>>>
> > >>>>>>
> > >>>>>>>I think i have another problem here, not related with 
> battery leak, 
> > >>>>>>>i just uploaded some photos , not very good quality, but 
the 
> battery 
> > >>>>>>>seems to be sealed, and the programmer is working despite 
> some press 
> > >>>>>>>memory recall buttons need cleaning or replacing. Well , 
the 
> synth 
> > >>>>>>>sound has some distortion and sounds like ring modulation, 
> this is 
> > >>>>>>>minimized if the negative/positive VCF EG Intensity is 
full 
> > >>>>>>>clockwise. The preset sounds are like no envelope sustain, 
> just a 
> > >>>>>>>short low (frequency) click...well, i'm not a keyboard 
> technician,
> > >>>>>>>just trying to make something here, otherwise i will have 
to 
> take
> > >>>>>>>the synth and schematics to a friend who is a technician 
> (works in 
> > >>>>>>>musical instruments, not vintage ones but...) and try to 
put 
> this 
> > >>>>>>>synth to play...have to say the brass and strings sections 
> are ok,  
> > >>>>>>>the split keyboard function switches and behavior are ok, 
> bend and 
> > >>>>>>>mod ok...well...lets see
> > >>>>>>>
> > >>>>>>>
> > >>>>>>>--- In PolySix@yahoogroups.com, "gil_we" <gil_we@y...> 
> wrote: 
> > >>>>>>>
> > >>>>>>>
> > >>>>>>>>Thanks, 
> > >>>>>>>>
> > >>>>>>>>I believe that this type of info should be shared all 
over 
> the net.  
> > >>>>>>>>The Trident's schematics are very rare - took me weeks to 
> get them; 
> > >>>>>>>>however, here they are. 
> > >>>>>>>>
> > >>>>>>>>I got my Trident in disasterous condition, nothing 
worked, 
> battery  
> > >>>>>>>>corrosion, bad chips, everything you may think of... Got 
it 
> work  
> > >>>>>>>>finally after doing the refurbishment step by step. This 
is 
> an  
> > >>>>>>>>incredible machine, one of the best ever made and 
> definately Korg's  
> > >>>>>>>>best Polysynth. 
> > >>>>>>>>
> > >>>>>>>>Let us know how you proceed, also if you can take some 
> pictues of the  
> > >>>>>>>>board it would help.
> > >>>>>>>>
> > >>>>>>>>
> > >>>>>>>>--- In PolySix@yahoogroups.com, "stagerhodes" 
> <stagerhodes@y...> wrote:
> > >>>>>>>>
> > >>>>>>>>
> > >>>>>>>>>Oh, i'm very pleased regarding this group , many thanks 
> for your 
> > >>>>>>>>>reply and the schematics beeing available for 
download... 
> i will 
> > >>>>>>>>>unmount the Trident may be tonight or tomorrow night and 
> will post my 
> > >>>>>>>>>sights inside. This is one of my favorite (regarding 
it's 
> wood design 
> > >>>>>>>>>and the sound, particularly the synth section) keyboards 
> from korg , 
> > >>>>>>>>>and i can say i tried almost them all at the time they 
> were beeing 
> > >>>>>>>>>produced since i was working demoing them in a shop. So 
> now is the 
> > >>>>>>>>>time for me to have some of them in full working 
> condiction...
> > >>>>>>>>>Art
> > >>>>>>>>>
> > >>>>>>>>>
> > >>>>>>>>>--- In PolySix@yahoogroups.com, "gil_we" <gil_we@y...> 
> wrote:
> > >>>>>>>>>
> > >>>>>>>>>
> > >>>>>>>>>>I didn't fully understand how the synth section acts on 
> this machine...
> > >>>>>>>>>>Also, is there corrosion (green colored) on the battery 
> and near it ?
> > >>>>>>>>>>Are there bad (black colored)traces ? are the signal 
and 
> synth boards 
> > >>>>>>>>>>correded as well on some areas ?
> > >>>>>>>>>>
> > >>>>>>>>>>Take extra care not to hurt anyting that works. 
> Particually, stay 
> > >>>>>>>>>>away from the 10 leg transistor type component at the 
> bottom left 
> > >>>>>>>>>>side of right bottom (signal) board. This one is 
> extremely sensitive 
> > >>>>>>>>>>to extreme temperature changes and is very rare and 
> expensive to get.
> > >>>>>>>>>>
> > >>>>>>>>>>You can use the schematics I uploaded to the Files 
> section.
> > >>>>>>>>>>
> > >>>>>>>>>>
> > >>>>>>>>>>--- In PolySix@yahoogroups.com, "stagerhodes" 
> <stagerhodes@y...> wrote:
> > >>>>>>>>>>
> > >>>>>>>>>>
> > >>>>>>>>>>>Hi,
> > >>>>>>>>>>>i just bought a Trident MK I in which the poly synth 
> section is 
> > >>>>>>>>>>>malfunctioning, i am almost certain that the problem 
is 
> the battery 
> > >>>>>>>>>>>question , and the leakage from it. It seems the tune 
is 
> ok, all notes 
> > >>>>>>>>>>>are sounding (brass and strings sections), in the 
synth 
> section one can 
> > >>>>>>>>>>>ear some sound (it is possible to ear the notes pitch, 
> but with some 
> > >>>>>>>>>>>strange effects in them) and the memory section is not 
> working which 
> > >>>>>>>>>>>leads me to the battery question. Is there any special 
> care i must have 
> > >>>>>>>>>>>in this model ?
> > >>>>>>>>>>>regards
> > >>>>>>>>>>>Art
> > >>>>>>>>>>>Portugal
> > >>>>>>>>>>>
> > >>>>>>>>>>>
> > >>>>>>>>>>
> > >>>
> > >>>PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6 
> > >>>Yahoo! Groups Links
> > >>>
> > >>>
> > >>>
> > >>> 
> > >>>
> > >>>
> > >>>
> > >>>
> > >>
> > > 
> > > PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6 
> > > Yahoo! Groups Links
> > > 
> > > 
> > > 
> > >
> >
>