Discussion about the Korg PolySix synthesizer

Hi,

I¹ve always used the Siliconix NSL32 and a 39K resistor at position R93 and
got very good results. Best of all they sell then Œoff the shelf¹ at
Farnell, which considerably saves time in sourcing them.

Cheers,
Andy


On 10/05/2011 23:50, "ltern_te" <ninonine@xs4all.nl> wrote:

>  
>  
>  
>    
> 
> Hi Don/ Andy and thanks for your advice and feedback,
> 
> Maybe a dummy question but how does one replace the P1501 with a VTL5CX ? Btw.
> did anyone find out already if its better to use a VTL5C2 or VTL5C3
> replacement?
> 
> Thanks for the answer(s) in advance.
> 
> Simon
> 
> --- In PolySix@yahoogroups.com <mailto:PolySix%40yahoogroups.com> , Andrew
> Jury <andy@...> wrote:
>> >
>> > Thanks Don,
>> > 
>> > You advice and expertise are much appreciated! I shall have a bit more of
>> an
>> > experiment, but I am at least ending up with the playable instrument for my
>> > efforts rather than the sound of a piano that has been dropped out of a
>> > window!
>> > 
>> > Cheers,
>> > Andy
>> > 
>> > 
>> > On 27/07/2010 13:35, "longenough2002" <backshall1@...> wrote:
>> > 
>>> > >  
>>> > >  
>>> > >  
>>> > >    
>>> > > 
>>> > > I tested this by setting VR1,2,3 to their midpoint, inserted a trimpot
>>> for R93
>>> > > and adjusted the pot for best scaling. It seemed to be about 40 point
>>> > > something K. 39K was the closest I had, so that's what I used. If you
>>> have
>>> > > more resistor choices (41K, 42K?) you might want to try one of those and
see
>>> > > if you get better results, or even leave in a 50K trimmer.
>>> > > Don B.
>>> > > 
>>> > > --- In PolySix@yahoogroups.com <mailto:PolySix%40yahoogroups.com>
>>> <mailto:PolySix%40yahoogroups.com> , Andrew
>>> > > Jury <andy@> wrote:
>>>>> > >> >
>>>>> > >> > Hi,
>>>>> > >> > 
>>>>> > >> > Just wanted to say that I have been getting on very well with the
>>>>> > >> > Silonex / 39k resistor mod. The only problem is the tuning is a bit
>>>>> > >> > critical towards the lower end of the keyboard. Apart from that all
is
>>>>> > >> > well and I am on my fourth successful repair.
>>>>> > >> > 
>>>>> > >> > Cheers,
>>>>> > >> > Andy
>>>>> > >> > 
>>>>> > >> > 
>>>>> > >> > 
>>>>> > >> > On 23 Jul 2010, at 16:31, "longenough2002" <backshall1@>
>>>>> > >> > wrote:
>>>>> > >> > 
>>>>>>>>> > >>>> > > > Shucks, just noticed a note in the "files" section from
gil_we
>>>>>>> > >>> > > back in Oct 2007 where he replaced the p1501 with a VTL5C3. I
wonder
>>>>>>> > >>> > > if the lower temperature coefficient of the VTL5C3 makes it a
better
>>>>>>> > >>> > > choice than the VTL5C2 for the tuning circuit? Some day, I
gotta
>>>>>>> > >>> > > read the rest of the stuff in there.
>>>>>>> > >>> > > Don B.
>>>>>>> > >>> > >
>>>>>>> > >>> > > --- In PolySix@yahoogroups.com
>>>>>>> <mailto:PolySix%40yahoogroups.com>  <mailto:PolySix%40yahoogroups.com> ,
M Ll
>>>>> > >>> <f115@> wrote:
>>>>>>>>> > >>>> > > >
>>>>>>>>> > >>>> > > > Thanks for the update!
>>>>>>> > >>> > >
>>>>>>>>> > >>>> > > > ________________________________
>>>>>>>>> > >>>> > > > From: longenough2002 <backshall1@>
>>>>>>>>> > >>>> > > > To: PolySix@yahoogroups.com
>>>>>>>>> <mailto:PolySix%40yahoogroups.com>  <mailto:PolySix%40yahoogroups.com>
>>>>>>>>> > >>>> > > > Sent: Sat, June 12, 2010 8:53:50 AM
>>>>>>>>> > >>>> > > > Subject: [PolySix] Re: Replacement for HTV P1501
>>>>>>>>> photocoupler?
>>>>>>>>> > >>>> > > >
>>>>>>>>> > >>>> > > >
>>>>>>>>> > >>>> > > > Got another Polysix in the shop with tuning problems.
Same sort of
>>>>>>> > >>> > > thing with octaves "stretched" and it couldn't be corrected
with the
>>>>>>> > >>> > > trim pots. The diode side of the photocoupler tested bad, so
it was
>>>>>>> > >>> > > time to go shopping again. This time, I thought I would try
one of
>>>>>>> > >>> > > the Vactrol parts, so I got a Vactec VTL5C2 from Small Bear
(same
>>>>>>> > >>> > > place I got the Silonex part). I replaced R93 with 22K (up
from
>>>>>>> > >>> > > 4.7K) and it seems to be working very well, so now we have a
couple
>>>>>>> > >>> > > of choices for replacing the P1501.
>>>>>>>>> > >>>> > > >
>>>>>>>>> > >>>> > > > Don B.
>>>>>>>>> > >>>> > > >
>>>>>>>>> > >>>> > > >
>>>>>>> > >>> > >
>>>>>>> > >>> > > 
>>>>> > >> > 
>>>>> > >> > 
>>>>> > >> > [Non-text portions of this message have been removed]
>>>>> > >> >
>>> > > 
>>> > >  
>>> > >    
>>> > > 
>>> > > 
>> > 
>> > 
>> > 
>> > [Non-text portions of this message have been removed]
>> >
> 
>  
>    
> 
> 



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