Archive of the former Yahoo!Groups mailing list: Discussion about the Korg PolySix synthesizer
Subject: Re: [PolySix] Re: Needed: calibration procedures for 366B
From: Johannes Hausensteiner <johau@gmx.net>
Date: 2006-04-26
Yes!
lionelcassin wrote:
> Thanks for the quick reply.
>
> Ok, so I adjust the KBD Track control panel knob so that I get +1.8V
> on CN05-06 and then adjust the KBD Track trimpot to get as close to an
> equal tempered keyboard as I can?
>
> LC
>
> --- In PolySix@yahoogroups.com, Johannes Hausensteiner <johau@...> wrote:
>
>> > But when I went to the manual, it says to test CN05-06 (which I take
>> > to mean Connector 5, Pin 6) and make sure you get +1.8V. When I test
>>This means that you have to adjust the KBD Track control panel knob
>>so that you read 1.8V at the connector and then make any trimpot
>>adjustments with this setting.
>>The adjustment procedure is part of the official Korg Polysix service
>>manual; there should be no error in it. The VCO alignment section
>>can be done faster and more accurate (by tuning the voices to each other
>>not each voice independently), but the filter section is OK.
>>... But the filter CF is not that accurate to regularily "tune" them
>>and play them as additional oscillators. You will end up in a mistuned
>>or "honkey tonkey" sound.
>>
>>The offset pot (VR7) sets the audio signal offset (= eliminating DC
>>component in audio), whereas "Filter F0" (VR8) sets the center frequency
>>of the VCF.
>>
>>Good luck!
>>
>>Johannes
>>
>>
>>
>>lionelcassin wrote:
>>
>>>I managed to cobble together a working Polysix from 2 dead units and a
>>>rebuilt 367 from Old Crow. The oscillators sound pretty in tune, so I
>>>left them alone.
>>>
>>>I'm a big fan of self-oscillating resonant filters, so I fiddled
>>>around with the frequency filter VRs to get all the filters tuned to
>>>the same note. Then I screwed around with the KBD TRACK (VR5) and KBD
>>>TRACK OFFSET (VR13) on the 367, knowing that if I sent everything
>>>screwy, I could refer back to the calibration manual I downloaded from
>>>Old Crow's site.
>>>
>>>But when I went to the manual, it says to test CN05-06 (which I take
>>>to mean Connector 5, Pin 6) and make sure you get +1.8V. When I test
>>>that pin, I get anywhere from -5 to +5 volts depending on the setting
>>>of Keyboard Track pot on the front panel. The manual doesn't mention
>>>KBD OFFSET.
>>>
>>>So my KBD TRACK, KBD OFFSET and FILTER F0 and OFFSET pots are probably
>>>set way out of factory standard and I have no way to get home.
>>>
>>>Thus my questions -
>>>
>>>1. Is the calibration manual off the Old Crow site the right manual to
>>>use for a 366B? If not, where can I get the right one?
>>>
>>>2. If the calibration manual I have is the right one, what am I doing
>>>wrong?
>>>
>>>3. Can one get tuned filters over the entire keyboard range, or is
>>>that practically impossible? The best I get was 1 - 2 octaves in tune.
>>>It sounds ok, but it could be better.
>>>
>>>4. What is the difference between VR7 (filter offset) and VR8
>
> (filter f0)?
>
>>>My overriding goal is to get the unit back to factory standard. Any
>>>help towards that end would be much appreciated.
>>>
>>>Thanks
>>>Lionel Cassin
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6
>>>Yahoo! Groups Links
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>
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> PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6
> Yahoo! Groups Links
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