Archive of the former Yahoo!Groups mailing list: Discussion about the Korg PolySix synthesizer

Hi,
the Polysix assignes the voices in a rotary order. It always chooses the next voice.

After you turn on the Polysix it needs a couple of seconds until the expo converter is self-calibrated. It is absolutely normal that the pitches are way off during this time.

You may also perceive 'popping' sounds the first few key presses because of the built in AGC in the effect section.

 

The poly six may assign the same note to the same voice if it's played again after releasing the key.

Lots of synths work this way.

So it may be that the first time it assigns the note the pitch is off, then the second time it's closer,

then the third time it's better, etc.

If that matches what you are seeing, then maybe this time it would be the 4051 that charges the

S&H caps for each oscillator.   If that chip has too much resistance, then the cap would not fully

charge the first time the key is assigned.  The cap voltage would get better after the second assignment,

and even better after the third.   That's the only thing I can think of that sort of matches what

you are describing.   The key MCU and DAC should put out the same voltage every time you

press a particular key.

BTW, if you put your scope on the S&H hold cap at the output of the 4051, it will probably

load it down enough to mess things up.   You may want to simply change the 4051 and see

if that fixes it.   Or use the scope to debug the problem some more first.

   Good luck.

---

From: "mpe1969@tpg.com.au [PolySix]" <PolySix@yahoogroups.com>
To: PolySix@yahoogroups.com
Sent: Thursday, May 7, 2015 9:05 AM
Subject: Re: [PolySix] Re: Key assign mode issue

 

I just did another check. The arpeggiator is working correctly. The reason why it was jumping up an octave on oscillator 6 was because I had the 'add lower octave' switch turned on. Which lifts the 6th oscillator an octave rather than add a lower one. With the octave switch turned off, all 6 oscillators play the same note. (phew)

Ghosting: when the poly is turned on, the ghosting is there for the first few hits. Waiting for a period of time between hits doesn't influence its behaviour (still present once the key is hit). 

I did a quick experiment. First hit. The note had a fast beating, hit again a slow beating (more like a slow phase), push again a fast beating, hit again, then back to normal. (approx)

When using the arp the notes has the same behaviour e.g. the first few repetitions distorted/beating then normal. Once the note is sounding normal it stays like this until I hit another key. The note next to it can cause the same problem

Initially I thought it was the previous note causing the beating. but I'm not so sure now as the beating/ghosting seems to change with each consecutive hit until it seems to resolve.....

I will connect the oscilloscope tomorrow night and trace the oscillator wave (see if I can find where the ghosting is introduced)

Thanks again

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