Korg Poly800/EX800 Users

Hi all,

Well, if there's one thing I've learned it's that you should never use
polls to make decisions because you can be sure that poll questions
were written and scripted by an idiot.

OK, down to business.

After looking at the poll results and seeing some of the responses I
was prompted to rethink the goals of the project. Taking into
consideration all of the work I've done so far and the progress made
it would be possible to take all of the new sysex functions (and more)
and put them into ROM space if we could add just one additional 8K
ROM. The challenge is to add that ROM without requiring major surgery
on the hardware. Well it turns out that a small board that would use
two 8K ROM's and one XOR logic gate chip could be made that would map
the second ROM into the same address space as the existing RAM. The
second ROM would be disabled for the low 2K of address space where the
2K RAM exists. This would mean that we would end up with 14K or ROM
instead of the existing 8K. The only problem with this concept is that
we don't get any additional RAM at all. This would mean that any new
sysex commands would have to be wedged into the existing RAM in such
as way as to not stomp all over the existing programming. I'll have to
do some testing to see what scratch RAM is available in that little 2K
RAM chip.

Then, there is the big retrofit project. This will give us so much
additional RAM, ROM and other hardware that we'll be able to transform
the Poly 800 and EX800 into something much more than we could ever
have imagined. It requires removing one IC and adding a much larger
plug in board. It will include two flash EEPROM's which means we'll be
able to download new code as it becomes available. And it will have
many new performance parameters and operational capabilities.

I think perhaps I should go for the easier retrofit kit first and go
from there.

Mike.

all i'm interested in is a decent mono mode with portamento :)

cheers,
kokoon

Hi Kokoon,

I miss my SH-101 for just that reason.

I spent some time thinking about how to do, as you so appropriately
put it, "decent portamento". At one point I was looking at using the
existing master DCO bend circuit to create the portamento but I fear
that might not give us a "decent" portamento and I just know it's
going take a lot of programming time to make it work. Another way to
do portamento would be to build a brand new master DCO that was able
to sweep across the entire 88 note keyboard (did I mention that I'm
going to provide full 88 key range as an selectable parameter?). But
such a master DCO will require even more circuitry so it will
definitely have to go into the full retrofit kit. I may try to use the
bend circuit first and see what sort of results I get, if they are
"decent" then perhaps we can avoid adding more hardware.

Isn't this fun!

Mike.

--- In korgpolyex@yahoogroups.com, "jure zitnik" <kokoon@...> wrote:
>
> all i'm interested in is a decent mono mode with portamento :)
>
> cheers,
> kokoon
>
> On 4/12/07, korgpolyex800 <korgpolyex800@...> wrote:
> >
> > Hi all,
> >
> > Well, if there's one thing I've learned it's that you should never use
> > polls to make decisions because you can be sure that poll questions
> > were written and scripted by an idiot.
> >
> > OK, down to business.
> >
> > After looking at the poll results and seeing some of the responses I
> > was prompted to rethink the goals of the project. Taking into
> > consideration all of the work I've done so far and the progress made
> > it would be possible to take all of the new sysex functions (and more)
> > and put them into ROM space if we could add just one additional 8K
> > ROM. The challenge is to add that ROM without requiring major surgery
> > on the hardware. Well it turns out that a small board that would use
> > two 8K ROM's and one XOR logic gate chip could be made that would map
> > the second ROM into the same address space as the existing RAM. The
> > second ROM would be disabled for the low 2K of address space where the
> > 2K RAM exists. This would mean that we would end up with 14K or ROM
> > instead of the existing 8K. The only problem with this concept is that
> > we don't get any additional RAM at all. This would mean that any new
> > sysex commands would have to be wedged into the existing RAM in such
> > as way as to not stomp all over the existing programming. I'll have to
> > do some testing to see what scratch RAM is available in that little 2K
> > RAM chip.
> >
> > Then, there is the big retrofit project. This will give us so much
> > additional RAM, ROM and other hardware that we'll be able to transform
> > the Poly 800 and EX800 into something much more than we could ever
> > have imagined. It requires removing one IC and adding a much larger
> > plug in board. It will include two flash EEPROM's which means we'll be
> > able to download new code as it becomes available. And it will have
> > many new performance parameters and operational capabilities.
> >
> > I think perhaps I should go for the easier retrofit kit first and go
> > from there.
> >
> > Mike.
> >
> >
> >
>

i think your original idea with the pitchbend might just work - why wouldn't it? is the midi pitchbend implemented in analogue (midi->DAC->joystick->ADC->master OSC) or completely digital?

kokoon

On 4/12/07, korgpolyex800 <korgpolyex800@...> wrote:

Hi Kokoon,

I miss my SH-101 for just that reason.

I spent some time thinking about how to do, as you so appropriately
put it, "decent portamento". At one point I was looking at using the
existing master DCO bend circuit to create the portamento but I fear
that might not give us a "decent" portamento and I just know it's
going take a lot of programming time to make it work. Another way to
do portamento would be to build a brand new master DCO that was able
to sweep across the entire 88 note keyboard (did I mention that I'm
going to provide full 88 key range as an selectable parameter?). But
such a master DCO will require even more circuitry so it will
definitely have to go into the full retrofit kit. I may try to use the
bend circuit first and see what sort of results I get, if they are
"decent" then perhaps we can avoid adding more hardware.

Isn't this fun!

Mike.

--- In korgpolyex@yahoogroups.com, "jure zitnik" <kokoon@...> wrote:
>
> all i'm interested in is a decent mono mode with portamento :)
>
> cheers,
> kokoon
>

> On 4/12/07, korgpolyex800 <korgpolyex800@...> wrote:
> >
> > Hi all,
> >
> > Well, if there's one thing I've learned it's that you should never use
> > polls to make decisions because you can be sure that poll questions
> > were written and scripted by an idiot.
> >
> > OK, down to business.
> >
> > After looking at the poll results and seeing some of the responses I
> > was prompted to rethink the goals of the project. Taking into
> > consideration all of the work I've done so far and the progress made
> > it would be possible to take all of the new sysex functions (and more)
> > and put them into ROM space if we could add just one additional 8K
> > ROM. The challenge is to add that ROM without requiring major surgery
> > on the hardware. Well it turns out that a small board that would use
> > two 8K ROM's and one XOR logic gate chip could be made that would map
> > the second ROM into the same address space as the existing RAM. The
> > second ROM would be disabled for the low 2K of address space where the
> > 2K RAM exists. This would mean that we would end up with 14K or ROM
> > instead of the existing 8K. The only problem with this concept is that
> > we don't get any additional RAM at all. This would mean that any new
> > sysex commands would have to be wedged into the existing RAM in such
> > as way as to not stomp all over the existing programming. I'll have to
> > do some testing to see what scratch RAM is available in that little 2K
> > RAM chip.
> >
> > Then, there is the big retrofit project. This will give us so much
> > additional RAM, ROM and other hardware that we'll be able to transform
> > the Poly 800 and EX800 into something much more than we could ever
> > have imagined. It requires removing one IC and adding a much larger
> > plug in board. It will include two flash EEPROM's which means we'll be
> > able to download new code as it becomes available. And it will have
> > many new performance parameters and operational capabilities.
> >
> > I think perhaps I should go for the easier retrofit kit first and go
> > from there.
> >
> > Mike.
> >
> >
> >
>

It might not work very well if the ADC is not very linear. In which
case the portamento would "wobble" through the octaves.

The other thing I will have to test is changing the TG note frequency
from one octave to the next while still operating all EG's and other
parameters without interruption.

In other words, will it be possible to tell the TG to change a note
frequency at any moment and not get any glitches in the frequency
output for that particular note TG.

If the ADC is linear enough and the TG can be switched at any time
then I think it would be very possible to do portamento without any
new circuitry.

Mike.

--- In korgpolyex@yahoogroups.com, "jure zitnik" <kokoon@...> wrote:
>
> i think your original idea with the pitchbend might just work - why
wouldn't
> it? is the midi pitchbend implemented in analogue
> (midi->DAC->joystick->ADC->master OSC) or completely digital?
>
> kokoon
>
> On 4/12/07, korgpolyex800 <korgpolyex800@...> wrote:
> >
> > Hi Kokoon,
> >
> > I miss my SH-101 for just that reason.
> >
> > I spent some time thinking about how to do, as you so appropriately
> > put it, "decent portamento". At one point I was looking at using the
> > existing master DCO bend circuit to create the portamento but I fear
> > that might not give us a "decent" portamento and I just know it's
> > going take a lot of programming time to make it work. Another way to
> > do portamento would be to build a brand new master DCO that was able
> > to sweep across the entire 88 note keyboard (did I mention that I'm
> > going to provide full 88 key range as an selectable parameter?). But
> > such a master DCO will require even more circuitry so it will
> > definitely have to go into the full retrofit kit. I may try to use the
> > bend circuit first and see what sort of results I get, if they are
> > "decent" then perhaps we can avoid adding more hardware.
> >
> > Isn't this fun!
> >
> > Mike.
> >
> > --- In korgpolyex@yahoogroups.com <korgpolyex%40yahoogroups.com>,
"jure
> > zitnik" <kokoon@> wrote:
> > >
> > > all i'm interested in is a decent mono mode with portamento :)
> > >
> > > cheers,
> > > kokoon
> > >
> > > On 4/12/07, korgpolyex800 <korgpolyex800@> wrote:
> > > >
> > > > Hi all,
> > > >
> > > > Well, if there's one thing I've learned it's that you should
never use
> > > > polls to make decisions because you can be sure that poll
questions
> > > > were written and scripted by an idiot.
> > > >
> > > > OK, down to business.
> > > >
> > > > After looking at the poll results and seeing some of the
responses I
> > > > was prompted to rethink the goals of the project. Taking into
> > > > consideration all of the work I've done so far and the
progress made
> > > > it would be possible to take all of the new sysex functions
(and more)
> > > > and put them into ROM space if we could add just one additional 8K
> > > > ROM. The challenge is to add that ROM without requiring major
surgery
> > > > on the hardware. Well it turns out that a small board that
would use
> > > > two 8K ROM's and one XOR logic gate chip could be made that
would map
> > > > the second ROM into the same address space as the existing
RAM. The
> > > > second ROM would be disabled for the low 2K of address space
where the
> > > > 2K RAM exists. This would mean that we would end up with 14K
or ROM
> > > > instead of the existing 8K. The only problem with this concept
is that
> > > > we don't get any additional RAM at all. This would mean that
any new
> > > > sysex commands would have to be wedged into the existing RAM
in such
> > > > as way as to not stomp all over the existing programming. I'll
have to
> > > > do some testing to see what scratch RAM is available in that
little 2K
> > > > RAM chip.
> > > >
> > > > Then, there is the big retrofit project. This will give us so much
> > > > additional RAM, ROM and other hardware that we'll be able to
transform
> > > > the Poly 800 and EX800 into something much more than we could ever
> > > > have imagined. It requires removing one IC and adding a much
larger
> > > > plug in board. It will include two flash EEPROM's which means
we'll be
> > > > able to download new code as it becomes available. And it will
have
> > > > many new performance parameters and operational capabilities.
> > > >
> > > > I think perhaps I should go for the easier retrofit kit first
and go
> > > > from there.
> > > >
> > > > Mike.
> > > >
> > > >
> > > >
> > >
> >
> >
> >
>

88 note range? I will check the progress page more often. Never thought of
that. It's a great feature!

>From: "korgpolyex800" <korgpolyex800@...>
>Reply-To: korgpolyex@yahoogroups.com
>To: korgpolyex@yahoogroups.com
>Subject: [korgpolyex] Re: Two different retrofit kit
>Date: Thu, 12 Apr 2007 18:56:15 -0000
>
>Hi Kokoon,
>
>I miss my SH-101 for just that reason.
>
>I spent some time thinking about how to do, as you so appropriately
>put it, "decent portamento". At one point I was looking at using the
>existing master DCO bend circuit to create the portamento but I fear
>that might not give us a "decent" portamento and I just know it's
>going take a lot of programming time to make it work. Another way to
>do portamento would be to build a brand new master DCO that was able
>to sweep across the entire 88 note keyboard (did I mention that I'm
>going to provide full 88 key range as an selectable parameter?). But
>such a master DCO will require even more circuitry so it will
>definitely have to go into the full retrofit kit. I may try to use the
>bend circuit first and see what sort of results I get, if they are
>"decent" then perhaps we can avoid adding more hardware.
>
>Isn't this fun!
>
>Mike.
>
>--- In korgpolyex@yahoogroups.com, "jure zitnik" <kokoon@...> wrote:
> >
> > all i'm interested in is a decent mono mode with portamento :)
> >
> > cheers,
> > kokoon
> >
> > On 4/12/07, korgpolyex800 <korgpolyex800@...> wrote:
> > >
> > > Hi all,
> > >
> > > Well, if there's one thing I've learned it's that you should never use
> > > polls to make decisions because you can be sure that poll questions
> > > were written and scripted by an idiot.
> > >
> > > OK, down to business.
> > >
> > > After looking at the poll results and seeing some of the responses I
> > > was prompted to rethink the goals of the project. Taking into
> > > consideration all of the work I've done so far and the progress made
> > > it would be possible to take all of the new sysex functions (and more)
> > > and put them into ROM space if we could add just one additional 8K
> > > ROM. The challenge is to add that ROM without requiring major surgery
> > > on the hardware. Well it turns out that a small board that would use
> > > two 8K ROM's and one XOR logic gate chip could be made that would map
> > > the second ROM into the same address space as the existing RAM. The
> > > second ROM would be disabled for the low 2K of address space where the
> > > 2K RAM exists. This would mean that we would end up with 14K or ROM
> > > instead of the existing 8K. The only problem with this concept is that
> > > we don't get any additional RAM at all. This would mean that any new
> > > sysex commands would have to be wedged into the existing RAM in such
> > > as way as to not stomp all over the existing programming. I'll have to
> > > do some testing to see what scratch RAM is available in that little 2K
> > > RAM chip.
> > >
> > > Then, there is the big retrofit project. This will give us so much
> > > additional RAM, ROM and other hardware that we'll be able to transform
> > > the Poly 800 and EX800 into something much more than we could ever
> > > have imagined. It requires removing one IC and adding a much larger
> > > plug in board. It will include two flash EEPROM's which means we'll be
> > > able to download new code as it becomes available. And it will have
> > > many new performance parameters and operational capabilities.
> > >
> > > I think perhaps I should go for the easier retrofit kit first and go
> > > from there.
> > >
> > > Mike.
> > >
> > >
> > >
> >
>
>

_________________________________________________________________
Descubra como mandar Torpedos do Messenger para o celular!
http://mobile.msn.com/

On Thu, 12 Apr 2007, korgpolyex800 wrote:

> In other words, will it be possible to tell the TG to change a note
> frequency at any moment and not get any glitches in the frequency output
> for that particular note TG.

======================

sure, most music teachers would say that a "glitch" is bad, but how many
musical genres have evolved from one or more glitches? who knows, maybe
the next "Big Thing(tm)" could be a glitchy portamento from a poly-800
with a hacked OS...? i'm assuming that portamento could be turned off, if
the effect isn't desired...


--
...atom

________________________
http://atom.smasher.org/
762A 3B98 A3C3 96C9 C6B7 582A B88D 52E4 D9F5 7808
-------------------------------------------------

"I am somehow less interested in the weight and
convolutions of Einstein's brain than in the near
certainty that people of equal talent have lived and
died in cotton fields and sweatshops."
-- Stephen Jay Gould

> sure, most music teachers would say that a "glitch" is bad, but how many
> musical genres have evolved from one or more glitches? who knows, maybe
> the next "Big Thing(tm)" could be a glitchy portamento from a poly-800
> with a hacked OS...? i'm assuming that portamento could be turned off, if
> the effect isn't desired...

I agree with this sentiment. And I think a good mono mode with even a "glitchy" portamento
would be very, very cool!

cya,
phoebe aka october71

I said 88 notes but was a little off there. The existing four octaves
will be extended to 6 (72 notes). The feature will be turned on by
selecting "4" for the octave setting (if you're in double mode then
setting 4 on either octave will set the other DCO to 4 as well). This
will turn off the octave shift (1-low,2-mid,3-high) altogether and
MIDI will respond to a full octave below and above the keyboard.

With regards to glitchy portamento. The bend is tunable using the bend
trim potentiometer. If I chose to implement portamento by sliding the
note a full octave before switching the underlying note frequency up a
full octave (while returning the bend back to zero). Then using the
bend potentiometer it would be possible to reduce the sliding. So the
portamento would never fully reach the next octave up. It would give a
funky stepping portamento. I could also implement the portamento by
sliding from one note to the next and only use the bend a little to
reach the next note. You do that by only making the ADC go up to the
next note OR I could still slide the note using the full ADC range but
then you would have to tune the range back down using the bend
potentiometer so that to get smooth portamento the bend trim would be
set very low indeed. That means that if we switch frequencies one note
at a time but tune the slide down then with bend pot set to maximum
the portamento would overshoot and could far surpass the next note in
the frequency stepping process. That might end up producing some
startling sliding stepping siren like effects.

I am leaning towards changing the function of the three Poly/ Chord/
Hold keys so that Poly becomes a mode button whereby you turn the unit
on and you are in Poly mode, you press it again and you go into poly
hold mode and you press again you go into Portamento mode, press again
you go into Portamento with hold mode. Once more, you go back to Poly
mode. That frees up the hold and chord buttons for other purposes and
it means that we can always add in new modes if we want.

Mike.

--- In korgpolyex@yahoogroups.com, "Phoebe" <october71@...> wrote:
>
> > sure, most music teachers would say that a "glitch" is bad, but
how many
> > musical genres have evolved from one or more glitches? who knows,
maybe
> > the next "Big Thing(tm)" could be a glitchy portamento from a
poly-800
> > with a hacked OS...? i'm assuming that portamento could be turned
off, if
> > the effect isn't desired...
>
> I agree with this sentiment. And I think a good mono mode with even
a "glitchy" portamento
> would be very, very cool!
>
> cya,
> phoebe aka october71
>