Discussion about the Korg PolySix synthesizer

After many years faithful service, my polysix seems to have developed
a tuning problem :-(

Usually when I first switch it on, and initially hit the keys, the
VCOs swirl around in pitch for about a second? (I presume that's some
kind of autotune routine or sthg.)

However, recently, when I turn it on, this doesn't happen, and the
oscillators stay at some kind of wierd tuning (all the notes seem
stretched out, the octaves are about a third or more off pitch!)

One time, I left it for about 20 minutes and when I tried again, it
was back to normal.
But yesterday it just remained in this wierd state.

Any suggestions to make it behave?
I made sure that the pitch bend wheel was centred at power up.
The VCOs are switched to "stretch tuning" inside, but that's never
been a problem before, and this is orders of magnitude more stretched
than that.

It's not a NiCd battery calamity, as my Polysix was upgraded a few
years ago to a "PolysixM" (with lithium battery) (Johannes
Hausensteiner's mod)

DAVID

Check the Files section as for how to replace the optocoupler.

Do not touch ANY of the trimpots, as once you replace the bad part it 
should stay in its normal tunning.


--- In PolySix@yahoogroups.com, "David Davis" <feline1@...> wrote:
>
> After many years faithful service, my polysix seems to have 
developed
> a tuning problem :-(
> 
> Usually when I first switch it on, and initially hit the keys, the
> VCOs swirl around in pitch for about a second? (I presume that's 
some
> kind of autotune routine or sthg.)
> 
> However, recently, when I turn it on, this doesn't happen, and the
> oscillators stay at some kind of wierd tuning (all the notes seem
> stretched out, the octaves are about a third or more off pitch!)
> 
> One time, I left it for about 20 minutes and when I tried again, it
> was back to normal.
> But yesterday it just remained in this wierd state.
> 
> Any suggestions to make it behave?
> I made sure that the pitch bend wheel was centred at power up.
> The VCOs are switched to "stretch tuning" inside, but that's never
> been a problem before, and this is orders of magnitude more 
stretched

> than that.
> 
> It's not a NiCd battery calamity, as my Polysix was upgraded a few
> years ago to a "PolysixM" (with lithium battery) (Johannes
> Hausensteiner's mod)
> 
> DAVID
>

Thanks very much for the advice - 
since that only involves replaceing two components on the boards, 
even my wretched soldering skills oughta be able to handle it - 
and it won't cost more than a few pounds...
Will definately give it a try!
DAVID

--- In PolySix@yahoogroups.com, "gil_we" <gil_we@...> wrote:

>
> Check the Files section as for how to replace the optocoupler.
> 
> Do not touch ANY of the trimpots, as once you replace the bad part it 
> should stay in its normal tunning.
> 
> 
> --- In PolySix@yahoogroups.com, "David Davis" <feline1@> wrote:
> >
> > After many years faithful service, my polysix seems to have 
> developed
> > a tuning problem :-(
> > 
> > Usually when I first switch it on, and initially hit the keys, the
> > VCOs swirl around in pitch for about a second? (I presume that's 
> some
> > kind of autotune routine or sthg.)
> > 
> > However, recently, when I turn it on, this doesn't happen, and the
> > oscillators stay at some kind of wierd tuning (all the notes seem
> > stretched out, the octaves are about a third or more off pitch!)
> > 
> > One time, I left it for about 20 minutes and when I tried again, it
> > was back to normal.
> > But yesterday it just remained in this wierd state.
> > 
> > Any suggestions to make it behave?
> > I made sure that the pitch bend wheel was centred at power up.
> > The VCOs are switched to "stretch tuning" inside, but that's never
> > been a problem before, and this is orders of magnitude more 
> stretched
> > than that.
> > 
> > It's not a NiCd battery calamity, as my Polysix was upgraded a few
> > years ago to a "PolysixM" (with lithium battery) (Johannes
> > Hausensteiner's mod)
> > 
> > DAVID
> >
>

Let us know if it helps...

Had the same exact problem on my Trident and it indeed was the expo 
coverter.

Thanks ;)



--- In PolySix@yahoogroups.com, "David Davis" <feline1@...> wrote:
>
> Thanks very much for the advice - 
> since that only involves replaceing two components on the boards, 
> even my wretched soldering skills oughta be able to handle it - 
> and it won't cost more than a few pounds...
> Will definately give it a try!
> DAVID
> 
> --- In PolySix@yahoogroups.com, "gil_we" <gil_we@> wrote:
> >
> > Check the Files section as for how to replace the optocoupler.
> > 
> > Do not touch ANY of the trimpots, as once you replace the bad 
part it 
> > should stay in its normal tunning.
> > 
> > 
> > --- In PolySix@yahoogroups.com, "David Davis" <feline1@> wrote:
> > >
> > > After many years faithful service, my polysix seems to have 
> > developed
> > > a tuning problem :-(
> > > 
> > > Usually when I first switch it on, and initially hit the keys, 
the
> > > VCOs swirl around in pitch for about a second? (I presume 
that's 
> > some
> > > kind of autotune routine or sthg.)
> > > 
> > > However, recently, when I turn it on, this doesn't happen, and 
the
> > > oscillators stay at some kind of wierd tuning (all the notes 
seem
> > > stretched out, the octaves are about a third or more off pitch!)
> > > 
> > > One time, I left it for about 20 minutes and when I tried 
again, it
> > > was back to normal.
> > > But yesterday it just remained in this wierd state.
> > > 
> > > Any suggestions to make it behave?
> > > I made sure that the pitch bend wheel was centred at power up.
> > > The VCOs are switched to "stretch tuning" inside, but that's 
never
> > > been a problem before, and this is orders of magnitude more 
> > stretched
> > > than that.
> > > 
> > > It's not a NiCd battery calamity, as my Polysix was upgraded a 
few

> > > years ago to a "PolysixM" (with lithium battery) (Johannes
> > > Hausensteiner's mod)
> > > 
> > > DAVID
> > >
> >
>

Well, it took a little while to get hold of a replacement
opto-resistor, but I fitted it last night...
pretty confident I got it soldered in right, 
but no joy :-(
The power-up autotune routine completed much quicker, 
but the semitones were still all stretched to hell.
Looks like my Polysix is gonna have to make a trip to
www.synthrepairservices.com ...

--- In PolySix@yahoogroups.com, "gil_we" <gil_we@...> wrote:

>
> Let us know if it helps...
> 
> Had the same exact problem on my Trident and it indeed was the expo 
> coverter.
> 
> Thanks ;)
> 
> 
> 
> --- In PolySix@yahoogroups.com, "David Davis" <feline1@> wrote:
> >
> > Thanks very much for the advice - 
> > since that only involves replaceing two components on the boards, 
> > even my wretched soldering skills oughta be able to handle it - 
> > and it won't cost more than a few pounds...
> > Will definately give it a try!
> > DAVID
> > 
> > --- In PolySix@yahoogroups.com, "gil_we" <gil_we@> wrote:
> > >
> > > Check the Files section as for how to replace the optocoupler.
> > > 
> > > Do not touch ANY of the trimpots, as once you replace the bad 
> part it 
> > > should stay in its normal tunning.
> > > 
> > > 
> > > --- In PolySix@yahoogroups.com, "David Davis" <feline1@> wrote:
> > > >
> > > > After many years faithful service, my polysix seems to have 
> > > developed
> > > > a tuning problem :-(
> > > > 
> > > > Usually when I first switch it on, and initially hit the keys, 
> the
> > > > VCOs swirl around in pitch for about a second? (I presume 
> that's 
> > > some
> > > > kind of autotune routine or sthg.)
> > > > 
> > > > However, recently, when I turn it on, this doesn't happen, and 
> the
> > > > oscillators stay at some kind of wierd tuning (all the notes 
> seem
> > > > stretched out, the octaves are about a third or more off pitch!)
> > > > 
> > > > One time, I left it for about 20 minutes and when I tried 
> again, it
> > > > was back to normal.
> > > > But yesterday it just remained in this wierd state.
> > > > 
> > > > Any suggestions to make it behave?
> > > > I made sure that the pitch bend wheel was centred at power up.
> > > > The VCOs are switched to "stretch tuning" inside, but that's 
> never
> > > > been a problem before, and this is orders of magnitude more 
> > > stretched
> > > > than that.
> > > > 
> > > > It's not a NiCd battery calamity, as my Polysix was upgraded a 
> few
> > > > years ago to a "PolysixM" (with lithium battery) (Johannes
> > > > Hausensteiner's mod)
> > > > 
> > > > DAVID
> > > >
> > >
> >
>

Are all VR's functional on that board ?


--- In PolySix@yahoogroups.com, "David Davis" <feline1@...> wrote:
>
> Well, it took a little while to get hold of a replacement
> opto-resistor, but I fitted it last night...
> pretty confident I got it soldered in right, 
> but no joy :-(
> The power-up autotune routine completed much quicker, 
> but the semitones were still all stretched to hell.
> Looks like my Polysix is gonna have to make a trip to
> www.synthrepairservices.com ...
> 
> --- In PolySix@yahoogroups.com, "gil_we" <gil_we@> wrote:
> >
> > Let us know if it helps...
> > 
> > Had the same exact problem on my Trident and it indeed was the 
expo 
> > coverter.
> > 
> > Thanks ;)
> > 
> > 
> > 
> > --- In PolySix@yahoogroups.com, "David Davis" <feline1@> wrote:
> > >
> > > Thanks very much for the advice - 
> > > since that only involves replaceing two components on the 
boards, 
> > > even my wretched soldering skills oughta be able to handle it - 
> > > and it won't cost more than a few pounds...
> > > Will definately give it a try!
> > > DAVID
> > > 
> > > --- In PolySix@yahoogroups.com, "gil_we" <gil_we@> wrote:
> > > >
> > > > Check the Files section as for how to replace the optocoupler.
> > > > 
> > > > Do not touch ANY of the trimpots, as once you replace the bad 
> > part it 
> > > > should stay in its normal tunning.
> > > > 
> > > > 
> > > > --- In PolySix@yahoogroups.com, "David Davis" <feline1@> 
wrote:
> > > > >
> > > > > After many years faithful service, my polysix seems to have 
> > > > developed
> > > > > a tuning problem :-(
> > > > > 
> > > > > Usually when I first switch it on, and initially hit the 
keys, 
> > the
> > > > > VCOs swirl around in pitch for about a second? (I presume 
> > that's 
> > > > some
> > > > > kind of autotune routine or sthg.)
> > > > > 
> > > > > However, recently, when I turn it on, this doesn't happen, 
and 
> > the
> > > > > oscillators stay at some kind of wierd tuning (all the 
notes 
> > seem
> > > > > stretched out, the octaves are about a third or more off 
pitch!)
> > > > > 
> > > > > One time, I left it for about 20 minutes and when I tried 
> > again, it
> > > > > was back to normal.
> > > > > But yesterday it just remained in this wierd state.
> > > > > 
> > > > > Any suggestions to make it behave?
> > > > > I made sure that the pitch bend wheel was centred at power 
up.
> > > > > The VCOs are switched to "stretch tuning" inside, but 
that's 
> > never
> > > > > been a problem before, and this is orders of magnitude more 
> > > > stretched
> > > > > than that.
> > > > > 
> > > > > It's not a NiCd battery calamity, as my Polysix was 
upgraded a 

> > few
> > > > > years ago to a "PolysixM" (with lithium battery) (Johannes
> > > > > Hausensteiner's mod)
> > > > > 
> > > > > DAVID
> > > > >
> > > >
> > >
> >
>

I haven't tested anything further yet, 
do you think maybe I should open it up again and make 
some more adjustments?
Perhaps even just flick the "stretch tuning"/"equal temperament"
switch and see what difference that makes?

Is it possible I just didn't solder the new vactrol in well?
(it was quite fiddly to get at some of the pins, since
it's a bigger component than the original dual-inline IC)
Or would it not work at all in that case?

--- In PolySix@yahoogroups.com, "gil_we" <gil_we@...> wrote:

>
> Are all VR's functional on that board ?
> 
> 
> --- In PolySix@yahoogroups.com, "David Davis" <feline1@> wrote:
> >
> > Well, it took a little while to get hold of a replacement
> > opto-resistor, but I fitted it last night...
> > pretty confident I got it soldered in right, 
> > but no joy :-(
> > The power-up autotune routine completed much quicker, 
> > but the semitones were still all stretched to hell.
> > Looks like my Polysix is gonna have to make a trip to
> > www.synthrepairservices.com ...
> > 
> > --- In PolySix@yahoogroups.com, "gil_we" <gil_we@> wrote:
> > >
> > > Let us know if it helps...
> > > 
> > > Had the same exact problem on my Trident and it indeed was the 
> expo 
> > > coverter.
> > > 
> > > Thanks ;)
> > > 
> > > 
> > > 
> > > --- In PolySix@yahoogroups.com, "David Davis" <feline1@> wrote:
> > > >
> > > > Thanks very much for the advice - 
> > > > since that only involves replaceing two components on the 
> boards, 
> > > > even my wretched soldering skills oughta be able to handle it - 
> > > > and it won't cost more than a few pounds...
> > > > Will definately give it a try!
> > > > DAVID
> > > > 
> > > > --- In PolySix@yahoogroups.com, "gil_we" <gil_we@> wrote:
> > > > >
> > > > > Check the Files section as for how to replace the optocoupler.
> > > > > 
> > > > > Do not touch ANY of the trimpots, as once you replace the bad 
> > > part it 
> > > > > should stay in its normal tunning.
> > > > > 
> > > > > 
> > > > > --- In PolySix@yahoogroups.com, "David Davis" <feline1@> 
> wrote:
> > > > > >
> > > > > > After many years faithful service, my polysix seems to have 
> > > > > developed
> > > > > > a tuning problem :-(
> > > > > > 
> > > > > > Usually when I first switch it on, and initially hit the 
> keys, 
> > > the
> > > > > > VCOs swirl around in pitch for about a second? (I presume 
> > > that's 
> > > > > some
> > > > > > kind of autotune routine or sthg.)
> > > > > > 
> > > > > > However, recently, when I turn it on, this doesn't happen, 
> and 
> > > the
> > > > > > oscillators stay at some kind of wierd tuning (all the 
> notes 
> > > seem
> > > > > > stretched out, the octaves are about a third or more off 
> pitch!)
> > > > > > 
> > > > > > One time, I left it for about 20 minutes and when I tried 
> > > again, it
> > > > > > was back to normal.
> > > > > > But yesterday it just remained in this wierd state.
> > > > > > 
> > > > > > Any suggestions to make it behave?
> > > > > > I made sure that the pitch bend wheel was centred at power 
> up.
> > > > > > The VCOs are switched to "stretch tuning" inside, but 
> that's 
> > > never
> > > > > > been a problem before, and this is orders of magnitude more 
> > > > > stretched
> > > > > > than that.
> > > > > > 
> > > > > > It's not a NiCd battery calamity, as my Polysix was 
> upgraded a 
> > > few
> > > > > > years ago to a "PolysixM" (with lithium battery) (Johannes
> > > > > > Hausensteiner's mod)
> > > > > > 
> > > > > > DAVID
> > > > > >
> > > > >
> > > >
> > >
> >
>

I had the same problem on my Korg Trident - the dual transistor 
responsible for the scaling was bad, the interval was about 3 halfs 
instead one half between each note to the one following it. That's 
why I still assume the problem lays there... Make sure you followed 
the instructions correctly. I presonally never replaced that one on 
the P6 but this is what the experience of other people shows. I 
wouldn't touch any tuning VR yet. Let us know how you proceed.



--- In PolySix@yahoogroups.com, "David Davis" <feline1@...> wrote:
>
> I haven't tested anything further yet, 
> do you think maybe I should open it up again and make 
> some more adjustments?
> Perhaps even just flick the "stretch tuning"/"equal temperament"
> switch and see what difference that makes?
> 
> Is it possible I just didn't solder the new vactrol in well?
> (it was quite fiddly to get at some of the pins, since
> it's a bigger component than the original dual-inline IC)
> Or would it not work at all in that case?
> 
> --- In PolySix@yahoogroups.com, "gil_we" <gil_we@> wrote:
> >
> > Are all VR's functional on that board ?
> > 
> > 
> > --- In PolySix@yahoogroups.com, "David Davis" <feline1@> wrote:
> > >
> > > Well, it took a little while to get hold of a replacement
> > > opto-resistor, but I fitted it last night...
> > > pretty confident I got it soldered in right, 
> > > but no joy :-(
> > > The power-up autotune routine completed much quicker, 
> > > but the semitones were still all stretched to hell.
> > > Looks like my Polysix is gonna have to make a trip to
> > > www.synthrepairservices.com ...
> > > 
> > > --- In PolySix@yahoogroups.com, "gil_we" <gil_we@> wrote:
> > > >
> > > > Let us know if it helps...
> > > > 
> > > > Had the same exact problem on my Trident and it indeed was 
the 
> > expo 
> > > > coverter.
> > > > 
> > > > Thanks ;)
> > > > 
> > > > 
> > > > 
> > > > --- In PolySix@yahoogroups.com, "David Davis" <feline1@> 
wrote:
> > > > >
> > > > > Thanks very much for the advice - 
> > > > > since that only involves replaceing two components on the 
> > boards, 
> > > > > even my wretched soldering skills oughta be able to handle 
it - 
> > > > > and it won't cost more than a few pounds...
> > > > > Will definately give it a try!
> > > > > DAVID
> > > > > 
> > > > > --- In PolySix@yahoogroups.com, "gil_we" <gil_we@> wrote:
> > > > > >
> > > > > > Check the Files section as for how to replace the 
optocoupler.
> > > > > > 
> > > > > > Do not touch ANY of the trimpots, as once you replace the 
bad 
> > > > part it 
> > > > > > should stay in its normal tunning.
> > > > > > 
> > > > > > 
> > > > > > --- In PolySix@yahoogroups.com, "David Davis" <feline1@> 
> > wrote:
> > > > > > >
> > > > > > > After many years faithful service, my polysix seems to 
have 
> > > > > > developed
> > > > > > > a tuning problem :-(
> > > > > > > 
> > > > > > > Usually when I first switch it on, and initially hit 
the 
> > keys, 
> > > > the
> > > > > > > VCOs swirl around in pitch for about a second? (I 
presume 
> > > > that's 
> > > > > > some
> > > > > > > kind of autotune routine or sthg.)
> > > > > > > 
> > > > > > > However, recently, when I turn it on, this doesn't 
happen, 
> > and 
> > > > the
> > > > > > > oscillators stay at some kind of wierd tuning (all the 
> > notes 
> > > > seem
> > > > > > > stretched out, the octaves are about a third or more 
off 
> > pitch!)
> > > > > > > 
> > > > > > > One time, I left it for about 20 minutes and when I 
tried 
> > > > again, it
> > > > > > > was back to normal.
> > > > > > > But yesterday it just remained in this wierd state.
> > > > > > > 
> > > > > > > Any suggestions to make it behave?
> > > > > > > I made sure that the pitch bend wheel was centred at 
power 
> > up.
> > > > > > > The VCOs are switched to "stretch tuning" inside, but 
> > that's 
> > > > never
> > > > > > > been a problem before, and this is orders of magnitude 
more 
> > > > > > stretched
> > > > > > > than that.
> > > > > > > 
> > > > > > > It's not a NiCd battery calamity, as my Polysix was 
> > upgraded a 
> > > > few
> > > > > > > years ago to a "PolysixM" (with lithium battery) 
(Johannes

> > > > > > > Hausensteiner's mod)
> > > > > > > 
> > > > > > > DAVID
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
>