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K5 analog filter mod?

K5 analog filter mod?

2005-11-02 by j brave

Can anyone with some electronics knowledge figure out how to hard-wire in 
some filters into the signal path, triggered by the internal keyboard? That 
would be the coolest, just solder in a little circuit board, drill a hole 
for the knobs and start playing...

Joel
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----- Original Message ----- 
From: <k5synth@yahoogroups.com>
To: <k5synth@yahoogroups.com>
Sent: Tuesday, November 01, 2005 12:31 PM
Subject: [k5synth] Digest Number 160



There are 4 messages in this issue.

Topics in this digest:

      1. Re: Sysex Help Needed
           From: "nelsonj_sce" <nelsonj_sce@...>
      2. K5 through Analog Filters
           From: "nelsonj_sce" <nelsonj_sce@...>
      3. Re: K5 through Analog Filters
           From: Antoine Desch\ufffdnes <antdes45@...>
      4. Re: K5 through Analog Filters
           From: "nelsonj_sce" <nelsonj_sce@...>


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Message: 1
   Date: Tue, 01 Nov 2005 00:35:13 -0000
   From: "nelsonj_sce" <nelsonj_sce@...>
Subject: Re: Sysex Help Needed

OK - I spent time and I think I understand the sysex.

If I want to send a single parameter, I have to first send
the "cursor" value, then the parameter value.  That means I cannot
call out a specific harmonic, but rather whatever harmonic is
already "active" can be adjusted.

If I want to just get a single harmonic, I have to do an elaborate
patch dump/handshake and basically send an entire patch.  That is no
good.

My only hope is to be able to program my BCR2000 to send two
paramaters.  First I send the parameter to select the harmonic, then
I send the parameter to change the value of the harmonic.  I will
have to try and trick the BCR2000 to "learn" this by writing my own
sysex scripts, and then sending these scripts to the BCR2000.  I hope
I can make it work.




--- In k5synth@yahoogroups.com, "nelsonj_sce" <nelsonj_sce@y...>
wrote:
>
> Hey group -
> I have been doing lots of fun stuff with my K5 and I have a
technical
> question for the sysex gurus out there (Lesile???)
>
> I got this Berhinger BCR2000 midi control surface and I have been
> playing with it on the K5.  Very cool - and only about $125US.
>
> First the good news:  The BCR2000 has a "learn" mode where
it "learns"
> simple sysex.  (More good news), the K5, with the sysex xmit turned
> on, sends sysex for just about every command. The BCR 2000 has 32
> knobs (but 8 can have four functions so it is like having 56 knobs)
24
> push buttons (but 8 can have four functions so it is like having 40
> push buttons).  As a result, you can program the BCR2000 knobs and
> buttons to control just about anything on the K5. (There are
problems
> with parameters that have +/- ranges, and all the knobs send values
> 1-128, so if the K5 parameter is 1-32, only the first 1/4 of the
knob
> turn is used.)
>
> Anyway, I want to assign each knob so that it adjusts each harmonic
on
> say S1(or at least 56 of my favorite harmonics).  Now the problem:
No
> matter which S1 harmonic I adjust on the K5, the K5 sends out the
same
> sysex.  There is also a parameter on the K5 to select which harmonic
> you want to edit.  I can assign this parameter to a knob (and I can
> then turn the knob to change values from 1 - 128), or I can assign
> specific harmonics to a button.  (For example, I can make it so that
> each time I hit button 1 on my BCR2000, harmonic X becomes active
for
> edit.)
>
> So, if I want to edit harmonic X, I have two choices: 1)I can turn a
> knob to select harmonic X, and then turn a different knob to adjust
> the level of harmonic X, or, 2) I can hit a button and jump to
> harmonic X, and then turn a knob to adjust the harmonic.
>
> Although this is better than nothing, it is still too much of a pain
> (or I only have 40 buttons and 63 harmonics) to make me happy.  I
want
> each knob to control its own harmonic. Period.
>
> Now my question(s):  When I look at the K5 sysex specification, it
> looks like each harmonic has its own sysex command.  Thus, it looks
> like I should be able to create a sysex on my computer that will
> control a specific harmonic.
> Q1: Is this correct?
> Q2: For example, if I want to control the level of S1 harmonic 5,
what
> is the EXACT sysex command I need to send to my K5?  (I know this
is a
> lot to ask, but I hope someone can help)
> Q3:  Just to make sure I get if, if I want to control the level of
S1
> harmonic 25, what is the EXACT sysex I need to send to my K5?
>
> Anyway, any help would be appreciated.  I tried useing several
editors
> (including DR. Ts) but they all have the same problem - they send a
> "generic" sysex that only lets you control the level of the harmonic
> that is currently selected.
>
> I just don't know how to decode the K5 sysex spec, but if someone
can
> get me started, I think I can get it.
>
> Thanks very much in advance for any help on this.  I just think it
> will be very cool to have a K5 with a bunch of knobs - each harmonic
> with its own knob so you can just dail and experiment with the
sounds.
>






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Message: 2
   Date: Tue, 01 Nov 2005 00:48:58 -0000
   From: "nelsonj_sce" <nelsonj_sce@...>
Subject: K5 through Analog Filters

I recently got a Roland MKS70 and figured out how to mod it so I can
run (6) external signals through its filters/VCA/Chorus.  I am
running the four outputs of the K5 through the MKS70 with the MKS70
in "mono mode" (Guitar synth mode).  By filtering the K5 midi output
through my computer and MidiOX, I can send different parts of the K5
keyboard to different midi channels, and then on to the filter of my
choice in the MSK70.

The result: Different notes on the K5 trigger their own filters.  It
is a true 4-voice poly board.  If I trigger more than four voices,
several notes go through the same filter in a paraphonic (?) mode.

In my opinion it sounds fantastic!!!  Just think about it, the K5
additive OSCs, stacked into multi layers, and then run through  the
very decent ANALOG filters/VCA (and Chorus)of the MSK70 (filters are
24db with Resonance and self-oscillation).  I can also add 2
additional DCOs (square/pulse/saw/noise) from the MKS70 - this helps
add some much needed low end to the K5, or whatever else I want (like
noise).  Think PPG 2.3 and a very rich sound.  The analog filters
just add so much life and beef to the K5 - I love it!

I will try to record some MP3 (K5 solo, K5 with DCOs, K5 with
DCOs+Filters, K5 with DCOs+Filters+Chorus).  Note that I upgraderthe
op-amps in my K5 to Burr/Brown, did the 147k resistor mod,and this
helps out also, but the filters are what really does the trick.

I am in love with the sound and have spent hours and hours playing
with the K5 through the MKS70.  My BCR2000 is programed to control
all the MKS70 settings so tweaking is very easy.

I hope to post some sounds in a week or so.  Stay tuned...





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________________________________________________________________________

Message: 3
   Date: Mon, 31 Oct 2005 19:58:21 -0500
   From: Antoine Desch\ufffdnes <antdes45@...>
Subject: Re: K5 through Analog Filters

Yeah, about your OPA4134 mod, I don't remember if you told the
improvement was big or small.

Since the free samples I've got from TI are SMD, I will have to build an
adapter. It's harder to solder, but I could put some filtering
components on the adapter board. Yay!

Also, something interesting to build would be one of the uCapps.de
(MIDIBox) projects and control some filters with it. I wonder what a
Moog filter on a K5 sounds??

nelsonj_sce a \ufffdcrit :

>I recently got a Roland MKS70 and figured out how to mod it so I can
>run (6) external signals through its filters/VCA/Chorus.  I am
>running the four outputs of the K5 through the MKS70 with the MKS70
>in "mono mode" (Guitar synth mode).  By filtering the K5 midi output
>through my computer and MidiOX, I can send different parts of the K5
>keyboard to different midi channels, and then on to the filter of my
>choice in the MSK70.
>
>The result: Different notes on the K5 trigger their own filters.  It
>is a true 4-voice poly board.  If I trigger more than four voices,
>several notes go through the same filter in a paraphonic (?) mode.
>
>In my opinion it sounds fantastic!!!  Just think about it, the K5
>additive OSCs, stacked into multi layers, and then run through  the
>very decent ANALOG filters/VCA (and Chorus)of the MSK70 (filters are
>24db with Resonance and self-oscillation).  I can also add 2
>additional DCOs (square/pulse/saw/noise) from the MKS70 - this helps
>add some much needed low end to the K5, or whatever else I want (like
>noise).  Think PPG 2.3 and a very rich sound.  The analog filters
>just add so much life and beef to the K5 - I love it!
>
>I will try to record some MP3 (K5 solo, K5 with DCOs, K5 with
>DCOs+Filters, K5 with DCOs+Filters+Chorus).  Note that I upgraderthe
>op-amps in my K5 to Burr/Brown, did the 147k resistor mod,and this
>helps out also, but the filters are what really does the trick.
>
>I am in love with the sound and have spent hours and hours playing
>with the K5 through the MKS70.  My BCR2000 is programed to control
>all the MKS70 settings so tweaking is very easy.
>
>I hope to post some sounds in a week or so.  Stay tuned...
>
>


________________________________________________________________________
________________________________________________________________________

Message: 4
   Date: Tue, 01 Nov 2005 04:43:42 -0000
   From: "nelsonj_sce" <nelsonj_sce@...>
Subject: Re: K5 through Analog Filters

My BB opamps did help a lot, but there is still noise.  You will be
able to add filters, that is interesting.  Please tell us how it goes.
PM if you need any help with the schematics.


--- In k5synth@yahoogroups.com, Antoine Desch\ufffdnes <antdes45@y...> wrote:
>
> Yeah, about your OPA4134 mod, I don't remember if you told the
> improvement was big or small.
>
> Since the free samples I've got from TI are SMD, I will have to
build an
> adapter. It's harder to solder, but I could put some filtering
> components on the adapter board. Yay!
>
> Also, something interesting to build would be one of the uCapps.de
> (MIDIBox) projects and control some filters with it. I wonder what a
> Moog filter on a K5 sounds??
>
> nelsonj_sce a \ufffdcrit :
>
> >I recently got a Roland MKS70 and figured out how to mod it so I can
> >run (6) external signals through its filters/VCA/Chorus.  I am
> >running the four outputs of the K5 through the MKS70 with the MKS70
> >in "mono mode" (Guitar synth mode).  By filtering the K5 midi output
> >through my computer and MidiOX, I can send different parts of the K5
> >keyboard to different midi channels, and then on to the filter of my
> >choice in the MSK70.
> >
> >The result: Different notes on the K5 trigger their own filters.  It
> >is a true 4-voice poly board.  If I trigger more than four voices,
> >several notes go through the same filter in a paraphonic (?) mode.
> >
> >In my opinion it sounds fantastic!!!  Just think about it, the K5
> >additive OSCs, stacked into multi layers, and then run through  the
> >very decent ANALOG filters/VCA (and Chorus)of the MSK70 (filters are
> >24db with Resonance and self-oscillation).  I can also add 2
> >additional DCOs (square/pulse/saw/noise) from the MKS70 - this helps
> >add some much needed low end to the K5, or whatever else I want (like
> >noise).  Think PPG 2.3 and a very rich sound.  The analog filters
> >just add so much life and beef to the K5 - I love it!
> >
> >I will try to record some MP3 (K5 solo, K5 with DCOs, K5 with
> >DCOs+Filters, K5 with DCOs+Filters+Chorus).  Note that I upgraderthe
> >op-amps in my K5 to Burr/Brown, did the 147k resistor mod,and this
> >helps out also, but the filters are what really does the trick.
> >
> >I am in love with the sound and have spent hours and hours playing
> >with the K5 through the MKS70.  My BCR2000 is programed to control
> >all the MKS70 settings so tweaking is very easy.
> >
> >I hope to post some sounds in a week or so.  Stay tuned...
> >
> >
>







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Re: [k5synth] K5 analog filter mod?

2005-11-02 by Antoine DeschĂȘnes

There's not much space IN the K5 to do this. Anyways, we would need to 
use MIDI for filter triggering. The best thing to do would be an 
external rack-mount or something like that. MIDIbox has everything for 
this. You could use a knob to make the filters work, or the module that 
makes an action per note, etc.

Ask in midibox.org's forum.
j brave a \ufffdcrit :
Show quoted textHide quoted text
> Can anyone with some electronics knowledge figure out how to hard-wire in 
> some filters into the signal path, triggered by the internal keyboard? That 
> would be the coolest, just solder in a little circuit board, drill a hole 
> for the knobs and start playing...
>
> Joel
>

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