Discussion about the Korg PolySix synthesizer

I'm listing all the capacitors from the KLM-367. I've no electronical
knowledge but I've managed to gather the informations from the service
manual. I know that there are different kinds of capacitors
(polyester, ceramic, tantal …). Would you please help me to find the
ones which suit the KLM-367 specifications ? What do CE and MS stands
for ?

I don't have every voltage informations either :-/

Take a look : http://100years.free.fr/p6/capacitors.htm

BTW I wonder if the quality of the capacitors can improve the way the
P6 sounds ?

Thank you for the helping hand.

Ben

So you know, the capacitor values are fairly useless without the
"type" of capacitor.  For the most part, swapping capacitors won't
help much except for the electrolytic (the metal can kinds), as they
dry out.  It would be a good idea to start with all of the power
supply caps, as they are the most important.  Without clean power
rails, nothing else will ever work as good as it should.

Are you sure you used the service manual to get your information?
The service manual that is linked to the group (and happens to be on
my website) at:
http://www.chromatest.net/POLY6_Service_Ensemble.pdf

has a parts list towards the end (section 9) which lists all the
capacitors and their values.  I wouldn't bother swapping out anything
other than the electrolytics. If you are decent with desoldering
through-hole components, this repair should take you a couple hours
and less than 10-15 dollars in parts.

On Mon, Jun 9, 2008 at 11:20 AM, n0disc0 <n0disc0@yahoo.com> wrote:
> I'm listing all the capacitors from the KLM-367. I've no electronical
> knowledge but I've managed to gather the informations from the service
> manual. I know that there are different kinds of capacitors
> (polyester, ceramic, tantal …). Would you please help me to find the
> ones which suit the KLM-367 specifications ? What do CE and MS stands
> for ?
>
> I don't have every voltage informations either :-/
>
> Take a look : http://100years.free.fr/p6/capacitors.htm
>
> BTW I wonder if the quality of the capacitors can improve the way the
> P6 sounds ?
>
> Thank you for the helping hand.
>
> Ben
>
>
> ------------------------------------
>
> PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6Yahoo! Groups Links
>
>
>
>



-- 
.sig
-Chromatest J. Pantsmaker
http://www.chromatest.net

Oh, and one thing about the caps, you can almost always replace old
ones with a higher voltage (same capacitance uF values), but not lower
voltage or different capacitance value.  Newer caps are generally
smaller, so you can get away with alternate voltages fairly easily.

On Mon, Jun 9, 2008 at 1:05 PM, Chromatest J. Pantsmaker
<chromatest@azburners.org> wrote:
> So you know, the capacitor values are fairly useless without the
> "type" of capacitor.  For the most part, swapping capacitors won't
> help much except for the electrolytic (the metal can kinds), as they
> dry out.  It would be a good idea to start with all of the power
> supply caps, as they are the most important.  Without clean power
> rails, nothing else will ever work as good as it should.
>
> Are you sure you used the service manual to get your information?
> The service manual that is linked to the group (and happens to be on
> my website) at:
> http://www.chromatest.net/POLY6_Service_Ensemble.pdf
>
> has a parts list towards the end (section 9) which lists all the
> capacitors and their values.  I wouldn't bother swapping out anything
> other than the electrolytics. If you are decent with desoldering
> through-hole components, this repair should take you a couple hours
> and less than 10-15 dollars in parts.
>
> On Mon, Jun 9, 2008 at 11:20 AM, n0disc0 <n0disc0@yahoo.com> wrote:
>> I'm listing all the capacitors from the KLM-367. I've no electronical
>> knowledge but I've managed to gather the informations from the service
>> manual. I know that there are different kinds of capacitors
>> (polyester, ceramic, tantal …). Would you please help me to find the
>> ones which suit the KLM-367 specifications ? What do CE and MS stands
>> for ?
>>
>> I don't have every voltage informations either :-/
>>
>> Take a look : http://100years.free.fr/p6/capacitors.htm
>>
>> BTW I wonder if the quality of the capacitors can improve the way the
>> P6 sounds ?
>>
>> Thank you for the helping hand.
>>
>> Ben
>>
>>
>> ------------------------------------
>>
>> PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6Yahoo! Groups Links
>>
>>
>>
>>
>
>
>
> --
> .sig
> -Chromatest J. Pantsmaker
> http://www.chromatest.net
>



-- 
.sig
-Chromatest J. Pantsmaker
http://www.chromatest.net

Hi Chromatest and thank you for your messages.

I've checked the section 9 of the service manual which lists all the
parts used for the P6. But it doesn't show which component is used on
which board. That's why I had checked the 367 circuit diagram instead
(section 4). But you were right. Once I had compared both sections
I've been able to write this updated version :

http://100years.free.fr/p6/capacitors-updated.html

I still don't understand what MS means (i.e. C40 10µF MS) but I've
found out that CE stands for « ceramic ».

Oldcrow recommands to use a 22PF capacitor for the 6MHz crystal
oscillator (C22). He also says « the 0.01uF bypass capacitors are now
0.1uF as they should have been ». Do you know which capacitors he is
talking about ? For the  C3, C20, C31, C36, C38, C39, C41 to 43 have a
0.01µF value.

Yours,

Ben

Here is a close-up of the KLM-367 with its different capacitors :

http://100years.free.fr/p6/capacitors-closeup.jpg

Could be useful for n00b like me oneday. :-P

Bypass caps are ones that are in the power supply or on power rails.
It's also called a filter cap.  Its job is to "smooth out" the power
and remove ripple (AC component on a DC power supply).  Thus, they'll
be on the voltage rails and they'll probably be monolithic ceramic
caps (as those are the best kind for bypass caps)

On Tue, Jun 10, 2008 at 7:18 AM, n0disc0 <n0disc0@yahoo.com> wrote:
> Here is a close-up of the KLM-367 with its different capacitors :
>
> http://100years.free.fr/p6/capacitors-closeup.jpg
>
> Could be useful for n00b like me oneday. :-P
>
>
> ------------------------------------
>
> PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6Yahoo! Groups Links
>
>
>
>



-- 
.sig
-Chromatest J. Pantsmaker
http://www.chromatest.net

But Oldcrow seems to talk about the KLM-367 especially :

See : (3rd paragraph)

http://www.oldcrows.net/~oldcrow/synth/korg/polysix/crowlm367/

I've also found useful informations on his site about the capacitors,
which confirm yours :


Tip #2 -- Replacing Old Capacitors

There are two types of parts to avoid, however : mylar capacitors and
tantalum capacitors.  There are an abundance of these two capacitor
types in old synthesizers, and they should be replaced first
among all the other capacitors.  Replace mylar capacitors with
polystyrene or polypropylene capacitors.  Use polypropylene capacitors
in the most tolerance-critical areas : oscillator timing capacitors,
tuned filter capacitive elements, and so on.  Polystyrene capacitors
can be used most everywhere else for things such as replacement S/H
hold capacitors, op-amp circuitry, etc.

For places where tantalum polarized capacitors were used (The
Prophet-5 had lots of these), replace them with aluminum electrolytic
parts of the same value.  Tantalum capacitors have a very low WVDC and
are the first parts to die if voltage spikes make it past the power
supply defeneses. In general, replace old aluminum electrolytics with
new ones.  Modern capacitor manufacturing techniques have yielded much
better parts, so take advantage of this. For power supply decoupling
on circuit boards, replace the usually 0.1uF ceramic disc capacitors
with monolithic dipped-ceramic parts.  Do the same for other values of
decoupling capacitors in the circuit.

Lastly--and importantly--replace the filter capacitors in the power
supply. These take a lot of abuse from the AC main line and should be
replaced at least once in the life of a synthesizer.

Well, remember that what he's talking about is *HIS* version of the
KLM-367, the CrowLM-367.

While his substitutions might be the perfect thing to do, I wouldn't
really know.  Replacing the ripple caps with bigger values should
help.  I still stand by my suggestion to replace all Power Supply caps
with new ones.  You'll get the most bang for your buck there.

On Tue, Jun 10, 2008 at 10:36 AM, n0disc0 <n0disc0@yahoo.com> wrote:
> But Oldcrow seems to talk about the KLM-367 especially :
>
> See : (3rd paragraph)
>
> http://www.oldcrows.net/~oldcrow/synth/korg/polysix/crowlm367/
>
> I've also found useful informations on his site about the capacitors,
> which confirm yours :
>
>
> Tip #2 -- Replacing Old Capacitors
>
> There are two types of parts to avoid, however : mylar capacitors and
> tantalum capacitors.  There are an abundance of these two capacitor
> types in old synthesizers, and they should be replaced first
> among all the other capacitors.  Replace mylar capacitors with
> polystyrene or polypropylene capacitors.  Use polypropylene capacitors
> in the most tolerance-critical areas : oscillator timing capacitors,
> tuned filter capacitive elements, and so on.  Polystyrene capacitors
> can be used most everywhere else for things such as replacement S/H
> hold capacitors, op-amp circuitry, etc.
>
> For places where tantalum polarized capacitors were used (The
> Prophet-5 had lots of these), replace them with aluminum electrolytic
> parts of the same value.  Tantalum capacitors have a very low WVDC and
> are the first parts to die if voltage spikes make it past the power
> supply defeneses. In general, replace old aluminum electrolytics with
> new ones.  Modern capacitor manufacturing techniques have yielded much
> better parts, so take advantage of this. For power supply decoupling
> on circuit boards, replace the usually 0.1uF ceramic disc capacitors
> with monolithic dipped-ceramic parts.  Do the same for other values of
> decoupling capacitors in the circuit.
>
> Lastly--and importantly--replace the filter capacitors in the power
> supply. These take a lot of abuse from the AC main line and should be
> replaced at least once in the life of a synthesizer.
>
>
> ------------------------------------
>
> PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6Yahoo! Groups Links
>
>
>
>



-- 
.sig
-Chromatest J. Pantsmaker
http://www.chromatest.net