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Ext filter signal?

Ext filter signal?

2015-05-27 by ultragalore@...

Hi All,


I have a hard time finding the modification for routing an external audio signal through the  2069 filter. Somewhere on the internet someone proposed to switch the noise signal but that does not sound very logical to me. I thought to just add a signal to pins 20/21 which are the normal 'signal in' pins.


I am a bit worried about 'breaking' the 2069 though, also heard they're pretty delicate... 


Does anyone have the good solution for this?

Re: [korgpolyex] Ext filter signal?

2015-05-27 by Gordonjcp

On Tue, May 26, 2015 at 11:56:39PM -0700, ultragalore@... [korgpolyex] wrote:
> Hi All,
>
>
> I have a hard time finding the modification for routing an external audio signal through the 2069 filter. Somewhere on the internet someone proposed to switch the noise signal but that does not sound very logical to me. I thought to just add a signal to pins 20/21 which are the normal 'signal in' pins.
>
>
> I am a bit worried about 'breaking' the 2069 though, also heard they're pretty delicate...
>
>
> Does anyone have the good solution for this?

Build an external filter :-)

By the time you've mucked about with this, you could have built something like the Yusynth Steiner Synthacon clone, which is four transistors, ten diodes and a bunch of passives. Oh, and Yves Usson used it in his design for the Arturia Minibrute!

Now, I wonder if you could replace the 2069 with such a beast. Or even add eight and have a properly polyphonic synth - with suitable software mods.

--
Gordonjcp MM0YEQ

Re: Ext filter signal?

2015-05-27 by ultragalore@...

Well I want to trigger the VCF on midi through the Poly (with HAWK kit) so I would like to keep it inside instead of building another wirely box...

Might try and run the DSP-G1 chip through it:
Here's a test with the G1 I  made, would like to run it through the 2069:
DSP-G1 Homebrew Synthesizer Testrun
DSP-G1 Homebrew Synthesizer Testrun
I built some hardware to control Jan stman's DSP-G1 Midi Synthesizer (LFO, Filters, envelopes). Multilayered tracks (bass, chord, arpeggio), only added so...
View on soundcloud.com
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Re: Ext filter signal?

2015-05-27 by ultragalore@...

Finally, I found this video which explains it very good:

pin 1, 19 filter in, and modify noise circuit indeed:
This is by far easier than building an external filter box.
External Audio passed thru a Korg Poly 800's filter
I used the audio output from a Roland JX-1, tapped it into the NJM2069 Filter IC chip and triggered the JX-1's voice via the Korg's MIDI out.. thus triggeri...
View on www.youtube.com
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Re: [korgpolyex] Re: Ext filter signal?

2015-05-28 by Michael Hawkins

This video is extremely cool but also shows how much we need a new tone generator to replace the MSM5232!!!

/Mike

From: "ultragalore@... [korgpolyex]" <korgpolyex@yahoogroups.com>
To: korgpolyex@yahoogroups.com
Sent: Wednesday, May 27, 2015 5:56 AM
Subject: [korgpolyex] Re: Ext filter signal?

 
Finally, I found this video which explains it very good:

pin 1, 19 filter in, and modify noise circuit indeed:
This is by far easier than building an external filter box.
External Audio passed thru a Korg Poly 800's filter
I used the audio output from a Roland JX-1, tapped it into the NJM2069 Filter IC chip and triggered the JX-1's voice via the Korg's MIDI out.. thus triggeri...
View on www.youtube.com
Preview by Yahoo
 





Re: [korgpolyex] Re: Ext filter signal?

2015-05-28 by Gordonjcp

On Thu, May 28, 2015 at 02:23:07AM +0000, Michael Hawkins korgpolyex800@... [korgpolyex] wrote:
> This video is extremely cool but also shows how much we need a new tone generator to replace the MSM5232!!!
> /Mike

It's pretty well-documented, right? Wouldn't it be possible to just do it all in a small CPLD these days? I'm guessing it's just a bunch of programmable dividers, not a lot to it.

If you didn't mind making a Poly-800 the size of a Jupiter 8, you could do it in discrete CMOS.

--
Gordonjcp MM0YEQ

Re: Ext filter signal?

2015-05-28 by bperkins211@...

That's my video of external audio ran thru the Poly's VCF.

Got a message yesterday on Youtube asking about it.. musta been you... have been so busy I had not had the time to reply yet, sorry.

I would have to revisit schematics again to see what I did.. I know I made an error in what I was saying in the vid.. that may be what is throwing you off.

I have two of Jans DSP-G1 chips.. they both arrived non functional and I still need to mail them back to Sweden to exchange for working ones.
I designed the stand alone GUI controller editor for him.. 

I had the same idea in mind and still do.. to run Jan's chip thru the Poly's amazing VCF.

My favorite trick to do with the VCF is control it with a DAW using the GUI I made to do Gating effects with the volume and/or the VCF

Like this..

KorgKontrolVST
KorgKontrolVST
This feature is not available right now. Please try again later.
View on www.yo...
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You will notice in the scroll bar 3 sections.
Top section is two chords played on the Poly.
Middle section is gating the DCA/Volume Full On/Off
Lower section is smoothly varying the VCF

you can watch the red VCF knob move as the pattern plays..
also you can see the ring of LED's around the GUI volume knob glow On/Off with the gating.

here's another with focus on the VCF control

KorgWobble2
KorgWobble2
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/Blaine 

Re: [korgpolyex] Re: Ext filter signal?

2015-05-28 by Gordonjcp

On Thu, May 28, 2015 at 05:26:11AM -0700, ultragalore@... [korgpolyex] wrote:
> Found a post here about how the youtube guy fiddled with it. I managed to get the sound in on pin 7, but am not completely happy with it though. I don't really understand what he means with the noise circuit.
>
> http://www.circuitbenders.co.uk/forum/index.php/topic,2099.0 http://www.circuitbenders.co.uk/forum/index.php/topic,2099.0

That appears to reference the Casio VL1, are you sure that's the right link?

--
Gordonjcp MM0YEQ

>
>
>
>
>
>

Re: Ext filter signal?

2015-05-28 by ultragalore@...

hey, yes - that would have been my question indeed. Good to meet up here then ;-)

Found a bug in Jan's DSP, he sent me a new one but I have to send the old one back too - Sweden's a long way out sometimes haha.

I have the 'Moog slayer knobs' on my poly which is nice to have the filter under 'real' control but like you're showing, with the HAWK you could change VCF with a DAW. That DSP-G1 Project I did was also about building potmeter control in the midi stream and merging in with incoming midi signals.

If this worked I could build this into the poly800 and set a bunch of potmeters on the poly to control the HAWK800 EG parameters while still receiving MIDI in.

However, it worked for 95% to my liking but on some occasions things got delayed in the midi stream somehow. Then payed work came by and now it's been laying around ever since... 

Would like to get the filter mod though, I hope you can find the time to look into it a bit more.

Re: [korgpolyex] Re: Ext filter signal?

2015-05-28 by Michael Hawkins

I already have plans to build a 40 pin drop in replacement for the MSM5232 using an STM8F7.

The plan is to allow it to be a drop in replacement for an unmodified (non HAWKed) resulting in 32 different waveforms available. It would be a bit annoying to have to select them using the harmonics and waveform parameters but it would work.

And then, for HAWKed Poly's, the number of waveforms and filter options would be dramatically more significant.

The STM32 series should be able to provide 8 fully independent DCO's and 8 fully independent DCF's along with all sorts of modulations and controls.

The project is progressing slowly because of having started my own business.

/Mike

From: "Gordonjcp gordon@... [korgpolyex]" <korgpolyex@yahoogroups.com>
To: "Michael Hawkins korgpolyex800@... [korgpolyex]" <korgpolyex@yahoogroups.com>
Sent: Thursday, May 28, 2015 4:41 AM
Subject: Re: [korgpolyex] Re: Ext filter signal?

 
On Thu, May 28, 2015 at 02:23:07AM +0000, Michael Hawkins korgpolyex800@... [korgpolyex] wrote:
> This video is extremely cool but also shows how much we need a new tone generator to replace the MSM5232!!!
> /Mike

It's pretty well-documented, right? Wouldn't it be possible to just do it all in a small CPLD these days? I'm guessing it's just a bunch of programmable dividers, not a lot to it.

If you didn't mind making a Poly-800 the size of a Jupiter 8, you could do it in discrete CMOS.

--
Gordonjcp MM0YEQ



MSM5232 replacement

2015-05-28 by Michael Hawkins

Sorry, I spoke wrong. The system on chip is going to be from the STM32 series.

/Mike

From: "Michael Hawkins korgpolyex800@... [korgpolyex]" <korgpolyex@yahoogroups.com>
To: "korgpolyex@yahoogroups.com" <korgpolyex@yahoogroups.com>
Sent: Thursday, May 28, 2015 9:48 AM
Subject: Re: [korgpolyex] Re: Ext filter signal?

 
I already have plans to build a 40 pin drop in replacement for the MSM5232 using an STM8F7.

The plan is to allow it to be a drop in replacement for an unmodified (non HAWKed) resulting in 32 different waveforms available. It would be a bit annoying to have to select them using the harmonics and waveform parameters but it would work.

And then, for HAWKed Poly's, the number of waveforms and filter options would be dramatically more significant.

The STM32 series should be able to provide 8 fully independent DCO's and 8 fully independent DCF's along with all sorts of modulations and controls.

The project is progressing slowly because of having started my own business.

/Mike



From: "Gordonjcp gordon@... [korgpolyex]" <korgpolyex@yahoogroups.com>
To: "Michael Hawkins korgpolyex800@... [korgpolyex]" <korgpolyex@yahoogroups.com>
Sent: Thursday, May 28, 2015 4:41 AM
Subject: Re: [korgpolyex] Re: Ext filter signal?

 
On Thu, May 28, 2015 at 02:23:07AM +0000, Michael Hawkins korgpolyex800@... [korgpolyex] wrote:
> This video is extremely cool but also shows how much we need a new tone generator to replace the MSM5232!!!
> /Mike

It's pretty well-documented, right? Wouldn't it be possible to just do it all in a small CPLD these days? I'm guessing it's just a bunch of programmable dividers, not a lot to it.

If you didn't mind making a Poly-800 the size of a Jupiter 8, you could do it in discrete CMOS.

--
Gordonjcp MM0YEQ





Re: MSM5232 replacement

2015-05-28 by bperkins211@...

interesting..

the STM32 is what I use on my multirotor's flight controller

The Flip32 (V2.5_Rev7.)
The Flip32 (V2.5_Rev7.)
32 bit fork of the MultiWii RC flight controller firmware Things are moving... We Flipping it and popped in an ATmega32u4 - The Flip Pro -  Arduino ...
View on www.readytoflyquad...
Preview by Yahoo

 

and this is what it's used for...

KISS 30A 6S Blackout Mini H
KISS 30A 6S Blackout Mini H
My first real chance to give the 6s powered Blackout a flogging. Special thanks to Felix for letting me try out the protoype KISS 30a esc's. They absolute...
View on youtu.be
Preview by Yahoo

 

I have an extra and plan to buy more of these FC boards.  They could easily be coded to work with your planned voice to play around with/test, I bet, Mike.

Plenty of the pins are already provided terminals on that board.. it also has gyros, accellerometers and a magnometer/compass.. you can also get a barometer on it for elevation readings.


I thought of making a home brew movement sensor out of one to use instead of pitch bend wheels/joysticks etc..

Re: [korgpolyex] Re: MSM5232 replacement

2015-05-29 by Michael Hawkins

Wow! I didn't realize that drone technology had gone high speed performance - in the air, that is. 160 Kph! Wow!

Thanks for the tip on the flip board. I shall check out the schematics and see if it will work for the proof of concept stage.

Thanks mate,

/Mike



From: "bperkins211@... [korgpolyex]" <korgpolyex@yahoogroups.com>
To: korgpolyex@yahoogroups.com
Sent: Thursday, May 28, 2015 12:36 PM
Subject: [korgpolyex] Re: MSM5232 replacement

 
interesting..

the STM32 is what I use on my multirotor's flight controller

The Flip32 (V2.5_Rev7.)
The Flip32 (V2.5_Rev7.)
32 bit fork of the MultiWii RC flight controller firmware Things are moving... We Flipping it and popped in an ATmega32u4 - The Flip Pro -  Arduino ...
View on www.readytoflyquad...
Preview by Yahoo

 
and this is what it's used for...

KISS 30A 6S Blackout Mini H
KISS 30A 6S Blackout Mini H
My first real chance to give the 6s powered Blackout a flogging. Special thanks to Felix for letting me try out the protoype KISS 30a esc's. They absolute...
View on youtu.be
Preview by Yahoo
 
I have an extra and plan to buy more of these FC boards.  They could easily be coded to work with your planned voice to play around with/test, I bet, Mike.
Plenty of the pins are already provided terminals on that board.. it also has gyros, accellerometers and a magnometer/compass.. you can also get a barometer on it for elevation readings.

I thought of making a home brew movement sensor out of one to use instead of pitch bend wheels/joysticks etc..