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Roland System 100m

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filter mods; multiple outputs on VCOs

filter mods; multiple outputs on VCOs

2007-10-03 by peterdwendt

Hello,

I just joined the forum, and immediately found the 121 HP VCF mod.  Nice.

There are two mods I would really like for my 100m:

1) switchable modes for the filters (not just LP or HP).  Someone on
Matrixsynth mentioned that this was possible, in reply to the posting
about the SEM-filter-in-121-box mod.

2) simultaneous waveform outputs on the 112 VCOs.  Having only one
waveform at a time per VCO is annoying.

Has anyone done these mods?

Thanks,

Peter

Re: filter mods; multiple outputs on VCOs

2007-10-04 by ryktnk

Hello

The switch in the M121 can be rewired to
switch the filter from the M121 HP Mod and back
to original wiring, it is 2Pole 3Way so this
is possible.
Bandpass on the M121 is more tricky . . .

Separate outs on VCO is easy, but you will need
some panel sockets spare.
Also it is quite easy to add a sine wave
shaper onto the VCO

There is a M110 sync in mod also, in the photo's
section.


-ryk


--- In RolandSystem100m@yahoogroups.com, "peterdwendt"
<peterwendt@...> wrote:
>
> Hello,
> 
> I just joined the forum, and immediately found the 121 HP VCF mod. 
Nice.
Show quoted textHide quoted text
> 
> There are two mods I would really like for my 100m:
> 
> 1) switchable modes for the filters (not just LP or HP).  Someone on
> Matrixsynth mentioned that this was possible, in reply to the posting
> about the SEM-filter-in-121-box mod.
> 
> 2) simultaneous waveform outputs on the 112 VCOs.  Having only one
> waveform at a time per VCO is annoying.
> 
> Has anyone done these mods?
> 
> Thanks,
> 
> Peter
>

Re: [RolandSystem100m] Re: filter mods; multiple outputs on VCOs

2007-10-04 by Peter Wendt

ryk,

Thanks. I suspected something like that, but I want to be extremely cautious before modding vintage electronics and drilling holes in faceplates.

Your suggestion for the M121 is sufficient for me, since i would just combine LP and HP to get BP and notch.

Peter

On Oct 3, 2007, at 5:01 PM, ryktnk wrote:

Hello

The switch in the M121 can be rewired to
switch the filter from the M121 HP Mod and back
to original wiring, it is 2Pole 3Way so this
is possible.
Bandpass on the M121 is more tricky . . .

Separate outs on VCO is easy, but you will need
some panel sockets spare.
Also it is quite easy to add a sine wave
shaper onto the VCO

There is a M110 sync in mod also, in the photo's
section.

-ryk

--- In RolandSystem100m@yahoogroups.com, "peterdwendt"
...> wrote:
>
> Hello,
>
> I just joined the forum, and immediately found the 121 HP VCF mod.
Nice.
>
> There are two mods I would really like for my 100m:
>
> 1) switchable modes for the filters (not just LP or HP). Someone on
> Matrixsynth mentioned that this was possible, in reply to the posting
> about the SEM-filter-in-121-box mod.
>
> 2) simultaneous waveform outputs on the 112 VCOs. Having only one
> waveform at a time per VCO is annoying.
>
> Has anyone done these mods?
>
> Thanks,
>
> Peter
>


RE: [RolandSystem100m] filter mods; multiple outputs on VCOs

2007-10-04 by synth ollie

hi and welcome ! :O)


I did the "sem-mod" on that m-121 you mentioned, but It was not really a "mod" to the original
cirquitry, the whole vcf pcb was replaced with a clone of a dual sem type svf

when it comes to separate outputs for the different waveforms on the vco´s, electronically
it would be very simple, unfortunately there is not much panelspace to have room for the
extra outputs, at least if you want it to look good, maybe an alternative would be to lead the
waveforms out of the module and use a piece of the 191j´s upper row of multiple jacks in some way.....


cheers,

OLLIE
Show quoted textHide quoted text
To: RolandSystem100m@yahoogroups.com
From: peterwendt@...
Date: Wed, 3 Oct 2007 23:30:31 +0000
Subject: [RolandSystem100m] filter mods; multiple outputs on VCOs

Hello,

I just joined the forum, and immediately found the 121 HP VCF mod. Nice.

There are two mods I would really like for my 100m:

1) switchable modes for the filters (not just LP or HP). Someone on
Matrixsynth mentioned that this was possible, in reply to the posting
about the SEM-filter-in-121-box mod.

2) simultaneous waveform outputs on the 112 VCOs. Having only one
waveform at a time per VCO is annoying.

Has anyone done these mods?

Thanks,

Peter



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Re: [RolandSystem100m] filter mods; multiple outputs on VCOs

2007-10-04 by Peter Wendt

Ollie,

Thanks.

Yes, I looked at the VCO circuit, and electrically it's just a matter of bringing out one jack per output. I don't want to damage the current modules with the mods, so I was thinking of external jacks like you mentioned. Something like the separate blocks of jacks in the old Technosaurus modular.

There is a good page about the 112 VCO here


so now i know how to disassemble it to do the mod. I'm a Yahoo group newbie, but i think we should post this link along with the other mods.

Nice monster system, by the way. I saw it at sys100m.org.

Peter


On Oct 4, 2007, at 1:57 PM, synth ollie wrote:

hi and welcome ! :O)


I did the "sem-mod" on that m-121 you mentioned, but It was not really a "mod" to the original
cirquitry, the whole vcf pcb was replaced with a clone of a dual sem type svf

when it comes to separate outputs for the different waveforms on the vco´s, electronically
it would be very simple, unfortunately there is not much panelspace to have room for the
extra outputs, at least if you want it to look good, maybe an alternative would be to lead the
waveforms out of the module and use a piece of the 191j´s upper row of multiple jacks in some way.....


cheers,

OLLIE


To: RolandSystem100m@yahoogroups.com
From: peterwendt@mac.com
Date: Wed, 3 Oct 2007 23:30:31 +0000
Subject: [RolandSystem100m] filter mods; multiple outputs on VCOs

Hello,

I just joined the forum, and immediately found the 121 HP VCF mod. Nice.

There are two mods I would really like for my 100m:

1) switchable modes for the filters (not just LP or HP). Someone on
Matrixsynth mentioned that this was possible, in reply to the posting
about the SEM-filter-in-121-box mod.

2) simultaneous waveform outputs on the 112 VCOs. Having only one
waveform at a time per VCO is annoying.

Has anyone done these mods?

Thanks,

Peter



Express yourself instantly with MSN Messenger! MSN Messenger


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