Wow,

I?m personally not "obsessed" with faster envelopes on my Matrix 12, I
rather get reminded of it whenever I play it, don?t need a scope for
that. It?s so fxxing great, but would be even greater with faster
envelopes IMHO.

I have some really fast machines like the P5 and the Minimoog D, so
it?s not like I have to get the M12 faster.

None of the machines I have are "perfect", in fact I have mods thought
out for most of them, but that?s the way I am I guess :)
I?m gonna syncmod the Mini next...hope that?s not like cursing in
church :)

When I have the time, I will start out by change the resistors on one
of the voiceboards like Mr Doidic suggested. After all, it worked out
on the SE-1.

Cheerio







--- In xpantastic@..., "Tony Cappellini" <cappy2112@...>
wrote:

I personally do not understand this general obsession with making

envelopes faster, the Xpander is perfection itself. It the real

world

the basses sound fine, gorgeous in fact, I love them..If you are
actually sitting down with a scope analysing speeds of enevelopes on
these machines, I personally think you've lost it. You need to
actually play it more, write some songs, use it as an instrument.

You

change stuff in it, you will ruin the sound I guarantee it.

One does not need a scope to experience the slow envelopes on the
Xpander, it is plainly audible.
The same goes for the OB8.

I personally do not understand this general obsession with making

envelopes faster, the Xpander is perfection itself. It the real world
the basses sound fine, gorgeous in fact, I love them..If you are
actually sitting down with a scope analysing speeds of enevelopes on
these machines, I personally think you've lost it. You need to
actually play it more, write some songs, use it as an instrument. You
change stuff in it, you will ruin the sound I guarantee it.

One does not need a scope to experience the slow envelopes on the
Xpander, it is plainly audible.
The same goes for the OB8.

BTW

I know a guy who has the source code for the Xpander, if anyone is
bored and wants to rewrite the OS over a weekend. ;-)
(I don't think he wants to give it away though)

There was talk that Neil Bradley (the guy who engineered Europa for
the Jupiter 6) would look into this, but Europa ended up taking too
much time.

开云体育

+1 !

eggwheatis schrieb:

开云体育

Hi !

I agree. If you speed up the CPU, all the software generated processes speed up too, not only the attack of envelopes.
Eventually, if the envelopes become faster, isn?t it they will be shorter also. One of the Xpander/Matrix12 advantages is, the duration of an envelope can be very long, especially if? the segments of the envelope are modulated.
I also think, all the Lfos would speed up, the track generators and the ramps,- their slowest settings would be faster then.
What happens to all the software generated VCAs ? I cannot imagine ...

I have a Roland D550 w/ a Musitronics memory expansion and speed kit as also midi-multimode feature.
This results in a faster response on incomming midi notes so the delay of notes if playing chord are reduced a lot.
The machine is 4 times faster w/ this kit.
The speed kit speeds up the cpu also, but they burned a completely new OS in a eprom on a daughter circuit board which compensates the LFO speed as also any other by software generated modulators for soundwise compatibility of all the patches for standard D50/550. The kit also includes a new quartz and some other new components on the daughter board.

So, I think, without a special modified OS for Xpander/Matrix12, there?s no solution to speed anything up without to change the behaviour and sound of an Xpander/Matrix12.
Could be a bad result if you cannot use all your patches anymore.


Tony Cappellini schrieb:

It would not change anything adding a faster 6809 and upping the
speed of the clocking circuit, you would have to change a lot more in
the circuit to cope with the faster speeds.. it would also create a
high risk of breaking things. Circuits do not like to be run at a
faster speed than they were designed for they usually break or dont
work at all. I would never risk this in such an expensive piece of
kit.

I personally do not understand this general obsession with making
envelopes faster, the Xpander is perfection itself. It the real world
the basses sound fine, gorgeous in fact, I love them..If you are
actually sitting down with a scope analysing speeds of enevelopes on
these machines, I personally think you've lost it. You need to
actually play it more, write some songs, use it as an instrument. You
change stuff in it, you will ruin the sound I guarantee it.

If you need ridiculously punchy bass, just buy a Moog Source or
something.

Just wanted to add I'm not being mean...these things come across
better face to face :o)

Phil...




--- In xpantastic@..., "Tony Cappellini" <cappy2112@...>
wrote:

On Tue, Sep 9, 2008 at 1:52 AM, analogholic <publik@...> wrote:

Hi everyone,
His answer:

"Hi Attila, To do the job right would be very difficult because,

as

you noticed, the envelopes are generated by the code of the 6809
microprocessor. Short of using a faster 6809 (assuming that you

could

get one) and modifying the code there is not much which can be

done.

Hitachi makes pin & instruction compatible replacement for the

6809,

but it's clock speed can go up to 3 or 4Mhz.
The 6309 has some additional instructiuons that the 6809 does not
have, but needs to be in a different mode to use them.

I don't think that this would just yield snappier envleopes though.

I

fear speeding up the CPU might make many things not work at all.

You may want to run this by Mr Doidic or MArcus to see what their

reply is.

On Tue, Sep 9, 2008 at 1:52 AM, analogholic <publik@...> wrote:

Hi everyone,
His answer:

"Hi Attila, To do the job right would be very difficult because, as
you noticed, the envelopes are generated by the code of the 6809
microprocessor. Short of using a faster 6809 (assuming that you could
get one) and modifying the code there is not much which can be done.

Hitachi makes pin & instruction compatible replacement for the 6809,
but it's clock speed can go up to 3 or 4Mhz.
The 6309 has some additional instructiuons that the 6809 does not
have, but needs to be in a different mode to use them.

I don't think that this would just yield snappier envleopes though. I
fear speeding up the CPU might make many things not work at all.

You may want to run this by Mr Doidic or MArcus to see what their reply is.

Hi everyone, my xpander seems to fail the VCO tune test randomly!some
voices fail during one test and pass on the next! there is no
cosistancy on the voices that fail,it can be any one of them!Some
times(rarely) the vco test passes! I have the same problem sometimes
with the Resonance and VCF but not as often!
I have totally rebuilt the power supply,changed the battery and output
bypass capacitors!All currents measure right so this is not a voltage
supply problem!
The only other part I can think of is the DAC or maybe the Timer?
Any thoughts?
Takis.

Hi everyone,

When I read the "percussive like patches"-thread, I was reminded that
I while ago (when the Matrix 12 was my only analog synth) that I (as
many others) was a bit frustrated with the M12?s slow enevelopes.

SoI wrote an email to one of the creators of this beast(Michel Doidic)
and asked what could be done. Here is our conversation:

"Mr Ryle, Mr Doidic, first off I want to thank you for being part of
designing (among other things) the fantastic Oberheim Matrix 12.
I have the incredible luck to have found one (Matrix 12) for sale in
Sweden. Although this is very "off topic", I would be incredibly
grateful and happy if you guys could try (who else could?) answer the
following question: Do you think it would be possible in some way to
modify the envelopes of the Matrix 12 to be faster ?
I know they are software envelopes, but today there are a lot of
softEnvs that are snappy, also on at least two analog synths which
have softwareEnvs (one is Studio Electronics Se-1/x) where if you
changed a resistor on the motherboard, the software envelopes became
dramatically faster and snappier, almost at Minimoog speed.
Could it be enough to change resistors in the right place, or would
it be necesarry to recode/reprogram the whole software for the Matrix
12? I know this a hard question, but a solution,if possible, would
mean that a fantastic synth would become the greatest of them all
IMHO.
I thank you once again and send you my best
regards Attila"

His answer:

"Hi Attila, To do the job right would be very difficult because, as
you noticed, the envelopes are generated by the code of the 6809
microprocessor. Short of using a faster 6809 (assuming that you could
get one) and modifying the code there is not much which can be done.
The Matrix 6 and 12 were designed about 25 years ago, and
microprocessors where a lot slower back then. There is still a bit of
hope however. The fastest time for the envelopes is about 2
milliseconds.
This could be reduce to 1 ms by changing RX51 for the VCA (where X
will be 3, 4, 5, 6 or 7 according to which of the six voice it
controls on each of the two voice boards) from 18K to 9.1K.
The next fastest time is set by the microprocessor and an analog
smoothing filter on the voltage control circuit (= Sample and Hold).
This time is set not only by the software but also by a resistor RX14
on each of the main voice PCB for the VCA control and by RX10 for the
VCF frequency control.
You may want to try reducing these resistors from their original 1 M
Ohm value to let say 500K Ohm. This will reduce that time from about
7 ms to about 3.5 ms. The draw back however is that you may get more
discontinuity in the shape of the modulation.
The next fastest times however will still be determined by the 6809
software and that will not change. Give it a try on one of the voice
and see if that goes toward what you want.
Hope that this helps a bit. Michel Doidic Line 6 CTO"

OK guys, what do you think?

I changed a resistor in my SE-1, and it become snappier (not
fantastic, but better)
Also, the Chroma has a reputaion of very slow envelopes, but same
thing there, if you remove a resistor or change it to a lower value,
envelopes supposedly become faster.

I would even go so far to check out the possibilities of putting in a
faster processor and find someone to recode the software.

Brainstorming please begin :)

They want orders of $100 or more.

What was the cost per part?

Nothing is ever posted on these sites, you have to call and tell them
how many you want to buy.
Even at $50-$100 a piece, it's better than letting a $1600 (or more)
synth lay useless, if the part ever failed.

that a few months ago I was only paying $7.00 for. It was cheaper at that point to redesign.

How are you going to resdesign and manufacture an IC unless you have a
semiconductor fab & mfg + experience doing it?

yes- many of the CEMs he has listed are alreayd sold out.
I got the last 3372 and a 3340, and still have some others from many years ago.
I don't have any 3374's though, but I heard these dont go bad on the
XP/M12 very often.

When I first moved to San Jose, I went to the company here that was
still selling these chips for $15, and bought a handfull.

Hello Randy,

Sounds right to me. I was thinking of the times I have seen techs
leave the synth plugged in and powered up to avoid dumping the memory.
It takes guts but some guys do it.

Best Regards

Karl
--- In xpantastic@..., William Cason <randycason102@...>
wrote:

If your xpander is not plugged into anything (e.g. the wall) while

unsoldering the battery, I it shouldn't matter if the iron is grounded
or not because there will be no >circuit to complete! Just make sure
your xpander's not plugged in, and its chassis isn't touching the same
ground that the iron's grounded to (like the chassis of another

plugged-in device) and you should be OK.

MHO,
Randy

--- On Sun, 9/7/08, Tony Cappellini cappy2112@... wrote:

From: Tony Cappellini cappy2112@...
Subject: Re: The Status of my Autotune & DAC Tests was Re:

[xpantastic] Re: It's official- my Xpander is sick

To: xpantastic@...
Date: Sunday, September 7, 2008, 12:11 PM

6.6 V seems very strange for the memory power supply. The battary
might need changing.

The Service manual reads that this should be 4.4 V with power on, and
2.xV with power off.
With power off, the voltage reading is correct.

I will probably change the battery too, since it's been about 10 years
after it was changed last.

If you are re-flowing the + side of this circuit ( M+5V) you better
make sure you have an un-grounded soldering Iron. If not
the +Mem supply will be shorted to ground and then the MEM will be
lost.

I will have the solder tech where I work do all of this for me since
he does soldering all day long.
I dont trust myself soldering on pcbs. He has a nice temperature
controlled iron with many removable tips.

Hope I caught you in time.

I havne't heard of an ungrounded soldering iron before, but I assume
you mean that the iron should not have the ground prong of the
power cord connected. This is easily done with an adapter.

I notice in the Xpander schematics D4 exsists twice. One is a diode
at the top edge of the board the other is an LED for the LFO. Now I

The D4 I'm referring to is on the Processor board-not the voice or pot
board. This is how the service manual refers to it.

If this is shiny brown, this may be soldering flux. This should
always be cleaned off the circuit board.
After about 5 - 10 years this will eat the solder and cause problems

It doesn't look like flux too me, and is far enough away from where
the solder flux would have been when it was soldered.

Well, I be talkin about U811 the main DAC which feeds the voice
board. The MP7614C-4 was mad by EXAR and is obsolete per their web
site, and the HS3140C-4 was made by SIPEX and is also obsolete.

I googled for this part, and many hits were found on websites that
specialize in getting rare parts.
They want orders of $100 or more.

It might not be a bad idea for us to do a group purchase of these, if
we could find a supplier who would sell us a small order.

I suppose with digging you can find this part out there somewhere
(repair shop or part house which specializes in obsolete parts but
you will pay quite a bit).

I wish there was a cross reference online that would tell you which
commercial devices also used these components
It would be much easier looking for an appliance than a chip.

Hi Tony,

> > Well, I be talkin about U811 the main DAC which feeds the voice
> > board. The MP7614C-4 was mad by EXAR and is obsolete per their web
> > site, and the HS3140C-4 was made by SIPEX and is also obsolete.

6.6 V seems very strange for the memory power supply. The battary
might need changing.

The Service manual reads that this should be 4.4 V with power on, and
2.xV with power off.
With power off, the voltage reading is correct.

I will probably change the battery too, since it's been about 10 years
after it was changed last.

If you are re-flowing the + side of this circuit ( M+5V) you better
make sure you have an un-grounded soldering Iron. If not
the +Mem supply will be shorted to ground and then the MEM will be
lost.

I will have the solder tech where I work do all of this for me since
he does soldering all day long.
I dont trust myself soldering on pcbs. He has a nice temperature
controlled iron with many removable tips.

Hope I caught you in time.

I havne't heard of an ungrounded soldering iron before, but I assume
you mean that the iron should not have the ground prong of the
power cord connected. This is easily done with an adapter.

I notice in the Xpander schematics D4 exsists twice. One is a diode
at the top edge of the board the other is an LED for the LFO. Now I

The D4 I'm referring to is on the Processor board-not the voice or pot
board. This is how the service manual refers to it.

If this is shiny brown, this may be soldering flux. This should
always be cleaned off the circuit board.
After about 5 - 10 years this will eat the solder and cause problems

It doesn't look like flux too me, and is far enough away from where
the solder flux would have been when it was soldered.

Well, I be talkin about U811 the main DAC which feeds the voice
board. The MP7614C-4 was mad by EXAR and is obsolete per their web
site, and the HS3140C-4 was made by SIPEX and is also obsolete.

I googled for this part, and many hits were found on websites that
specialize in getting rare parts.
They want orders of $100 or more.

It might not be a bad idea for us to do a group purchase of these, if
we could find a supplier who would sell us a small order.

I suppose with digging you can find this part out there somewhere
(repair shop or part house which specializes in obsolete parts but
you will pay quite a bit).

I wish there was a cross reference online that would tell you which
commercial devices also used these components
It would be much easier looking for an appliance than a chip.

Thanks Phillipe,
You are too kind. Truth is, You fixed it by doing all the
heavy lifting(real work).
I just made some suggestions.
Glad I Could Help
Karl


--- In xpantastic@..., "philipperyckman" <caractere@...>
wrote:

All of you,

Guys, trust Karl: he's a genius. He fixed my Xpander in no time
across the atlantic !! Do exactly the steps he recommends.
Best regards to all,
Philippe

Hi Tony,
Have been out of pocket for a few days ( building a parade float).
Back now.
--- In xpantastic@..., "Tony Cappellini" <cappy2112@...>
wrote:

I went through all the DC voltmeter measurements in the service
manuel. Everything looks good (to me) except for Step 3, +5M text.
On the right side of D4 (as I am facing the Processor Board,
sometimes I measured 6.6 v, other times I measured 3.9 to 4.9 volts.
I suspect there is a bad solder joing on D4, so I will reflow this.

6.6 V seems very strange for the memory power supply. The battary
might need changing.
If you are re-flowing the + side of this circuit ( M+5V) you better
make sure you have an un-grounded soldering Iron. If not
the +Mem supply will be shorted to ground and then the MEM will be
lost.
Hope I caught you in time.
I notice in the Xpander schematics D4 exsists twice. One is a diode
at the top edge of the board the other is an LED for the LFO. Now I
am sure you know the difference between a diode and an LED but I
thought I would mention it. This was changed in the M12 schems.

I looked at C3 and there is some dry dusty residue on the negative
side of C3.
There is less residue on the negative side of C1.

If this is shiny brown, this may be soldering flux. This should
always be cleaned off the circuit board.
After about 5 - 10 years this will eat the solder and cause problems

These caps are old, so I might as well just replace them all at the
same time.
There are 4 more electrolytic caps on the PS board, but their leads
are right up against the PCB, so I can't see if they are leaking.

I have not seen this in Oberheims, but many times in old Korgs /
Rolands.

It will be worth the money to have all the voices re-capped.

Good Idea, I am thinking off doing this myself. When I change my
battary.

In a previous email you referred to a RARE DAC. The service manual
references several whose part numbers look like easy to find
components to me.
Which rare DAC are you referring to?

Well, I be talkin about U811 the main DAC which feeds the voice
board. The MP7614C-4 was mad by EXAR and is obsolete per their web
site, and the HS3140C-4 was made by SIPEX and is also obsolete.
I suppose with digging you can find this part out there somewhere
(repair shop or part house which specializes in obsolete parts but
you will pay quite a bit).

Good Luck

Karl

In 1998 or so, I bought my Xpander sight unseen from a guy in Southern
California. I was living in San Jose at the time, about 6 hours away
by car.
(someone gave me a tip and I followed up on it).
I called the guy, asked him lots of questions. I really took a chance
buying something as expensive as this blindly from an "unknown"
person.

He packed and shipped it, while I was sweating blood hoping it would
arrive. When the box came I started unpacking it, when I heard some
rattling inside.
I stopped there, and called UPS to file a claim. I also called the
owner to let him know what happened.

After opening the box, I opened the Xpander slowly. The transformer
bolts were loose and the transformer had about 1+ inch or so of
vertical travel.
Fortunately the only components that were broken were a cheap OpAmp,
diode and resistor. All of which I think are for the cassette zero
crossing detector, so nothing really critical, but still it was an
unerving experience.
I took the Xpander to someone in San Francisco and he fixed it
relatively cheaply.

I am lucky the shock of the transformer bouncing didn't damage the
VFD's or crack the circuit boards.

Well, I have had this baby about 10 years, and it's been in good shape.

Karl,
I went through all the DC voltmeter measurements in the service manuel.
Everything looks good (to me) except for Step 3, +5M text.
On the right side of D4 (as I am facing the Processor Board, sometimes
I measured 6.6 v, other times I measured 3.9 to 4.9 volts.
I suspect there is a bad solder joing on D4, so I will reflow this.

Power Supply:
If you have a buzz in the audio output Then the power supply may be
going. An easy way to tell is to get a new large capacitor of the
same value and voltage . And use jumper leads to jump it across the
suspect cap. If the buzz goes away then Replace Em. You will probobly
not be able to find exact matches. So some retrofitting may be in
order.

I looked at C3 and there is some dry dusty residue on the negative side of C3.
There is less residue on the negative side of C1.

These caps are old, so I might as well just replace them all at the same time.
There are 4 more electrolytic caps on the PS board, but their leads
are right up against the PCB, so I can't see if they are leaking.

Voice 1 Problem:
I suspect a bypass capacitor located at the output of each voice. I
keep seeing this part failing in more and more M12/Xpanders.( mine
included) So get a new 2.2uF 50 volt electrolytic cap. and replace
C749 (for Voice 1). It is toward the front of the board. This same
value part is all over the voice circuits. So.. It would not be a bad
Idea to get a bunch of em, and replace all Cx49s. Again you gotta
observe polarity.

I dont want to trust my baby Xpander to my shaky hands that haven't
used a soldering iron regularly since 1985, so I will have a pro do
this for me.
It will be worth the money to have all the voices re-capped.

I don't know about the DAC mono test, but if you can get the voices
to tune, then the DAC's probobly good.

In a previous email you referred to a RARE DAC. The service manual
references several whose part numbers look like easy to find
components to me.
Which rare DAC are you referring to?

Thanks


Tony

开云体育

There?s nothing wrong with it,- use it as a synth ...
Try to create?a wovel sounding selfplaying patch which sings the song "Rolling Home" ...

:-D