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Starting from scratch

Starting from scratch

2005-02-18 by t0ny_mowbray

Hi,

I used to have a Korg PolySix and a mono (can't remember the model)
with 1/4" jacks over it. Unfortunately I sold them both and now I am
kicking myself!

I want to build a systh from scratch and I really need some help to
point me in the right direction. I am an Electrician and I have
Electronic trades on top. I am a licenced amateur radio operator
(VK2AGM) and I probably have the skills necessary to do it all (my
soldering iron is my friend...). I have also worked in the computer
industry since Intel created the 8080 uP.

Any help woul dbe most appreciated. Thanks in advance.

Re: Starting from scratch

2005-02-19 by bbluthang

hello
if you are fine with components and soldering, CGS is a good place
to begin.

best to start considering a regulated +/-15V power supply and what
will you use to house your synth. cabinet, old toolbox, fracrak?
make your own panels or follow a format? schaeffer, stooge,
screenprinting?
also, how will you play the synth? keyboard, sequencer, joysticks,
midi?

these parts of the process tend to take more time and/or money than
anything else.
its probably worth looking around to see what others have done to
get an idea of your options.

andrew




--- In cgs_synth@yahoogroups.com, "t0ny_mowbray" <tmowbray@i...>
wrote:
Show quoted textHide quoted text
>
> Hi,
>
> I used to have a Korg PolySix and a mono (can't remember the model)
> with 1/4" jacks over it. Unfortunately I sold them both and now I
am
> kicking myself!
>
> I want to build a systh from scratch and I really need some help to
> point me in the right direction. I am an Electrician and I have
> Electronic trades on top. I am a licenced amateur radio operator
> (VK2AGM) and I probably have the skills necessary to do it all (my
> soldering iron is my friend...). I have also worked in the computer
> industry since Intel created the 8080 uP.
>
> Any help woul dbe most appreciated. Thanks in advance.

Re: Starting from scratch

2005-02-19 by hitchindave

Hi.

Aim for a simple monophonic synth to start with.
A simple basic system would be a VCO, mixer, VCF, VCA,
LFO, and an envelope generator (or ADSR). I'd recommend
starting by building an EQ or VC filter - once it's finished, you can
test it easily, and start using it straight away. Ken makes VCO,
VCF, and nifty dual LFO PCBs, as well as many other unique
boards. There are many sites on the net with schematics, pcb
foil patterns, and pcbs for sale.
Google away for ADSR, VCA etc.

In terms of controlling the synth, I'd go for a MIDI - CV converter,
as MIDI is very common - there's loads of MIDI computer
software around, and even cheap portable keyboards often
have basic MIDI .
PaiA do an 8-channel job, (MIDI2CV8) which comes as a
complete kit. It was the one of the first modules I built, it had
excellent building instructions,and worked first time.

As Andrew said, get a good ±15v power supply first, with at least
500mA or more per rail.
I couldn't decide at first how to house the synth, so I got some
small hex M3 spacers (about 20mm long) and fixed them to the
boards. (M3 seems to be the mounting hole size for most
boards I've come across.) Then I drilled corresponding holes
halfway through a 2 foot by 3 foot piece of half inch MDF to take
the spacers.
This way the boards are quickly removable from the big MDF
board and can be interconnected easily . Pots/switches were
mounted in an old piece of 3mm plywood on wooden supports
at the back of the MDF board.
It wasn't pretty, but I was able to get the first few modules
working, while I decided what the final synth would look like.

It still isn't finished, - beware mission creep! :-)

Good luck and have fun.

Cheers,

Dave


Show quoted textHide quoted text

--- In cgs_synth@yahoogroups.com, "bbluthang"
<jumpswine@h...> wrote:
>
> hello
> if you are fine with components and soldering, CGS is a good
place
> to begin.
>
> best to start considering a regulated +/-15V power supply and
what
> will you use to house your synth. cabinet, old toolbox, fracrak?
> make your own panels or follow a format? schaeffer, stooge,
> screenprinting?
> also, how will you play the synth? keyboard, sequencer,
joysticks,
> midi?
>
> these parts of the process tend to take more time and/or
money than
> anything else.
> its probably worth looking around to see what others have
done to
> get an idea of your options.
>
> andrew
>
>
>
>
> --- In cgs_synth@yahoogroups.com, "t0ny_mowbray"
<tmowbray@i...>
> wrote:
> >
> > Hi,
> >
> > I used to have a Korg PolySix and a mono (can't remember
the model)
> > with 1/4" jacks over it. Unfortunately I sold them both and now
I
> am
> > kicking myself!
> >
> > I want to build a systh from scratch and I really need some
help to
> > point me in the right direction. I am an Electrician and I have
> > Electronic trades on top. I am a licenced amateur radio
operator
> > (VK2AGM) and I probably have the skills necessary to do it all
(my
> > soldering iron is my friend...). I have also worked in the
computer
> > industry since Intel created the 8080 uP.
> >
> > Any help woul dbe most appreciated. Thanks in advance.

Re: Starting from scratch

2005-02-19 by Laurie Biddulph

--- In cgs_synth@yahoogroups.com, "t0ny_mowbray" <tmowbray@i...>
wrote:
Show quoted textHide quoted text
>
> Hi,
>
> I used to have a Korg PolySix and a mono (can't remember the model)
> with 1/4" jacks over it. Unfortunately I sold them both and now I am
> kicking myself!
>
> I want to build a systh from scratch and I really need some help to
> point me in the right direction. I am an Electrician and I have
> Electronic trades on top. I am a licenced amateur radio operator
> (VK2AGM) and I probably have the skills necessary to do it all (my
> soldering iron is my friend...). I have also worked in the computer
> industry since Intel created the 8080 uP.
>
> Any help woul dbe most appreciated. Thanks in advance.
Hi Tony,
Have a look at the ASM-2 at www.elby-designs.com. This is an analogue
synth on a single pcb. Add a case, panel, transformer and MIDI and
you are up an running. The ASM-2 contains all the basic sound modules
you need to get started and gives you the flexibility to configure
the synth in a variety of different ways.

Re: Starting from scratch

2005-02-19 by Ryan Williams

there is quite a bit to consider when starting a synth project. do you
want stand alone or pre-patched? Ken's CGS modules are great and there
are some really neat and unique designs. you will most likely want to
build some other more generic modules at some point. I suggest doing
this at first so that you'll have the basic synth setup, then add the
more exotic modules later. this is assuming you choose a modular type synth.

I reccomend joining the Synth-DIY list if you haven't already:
http://dropmix.xs4all.nl/rick/Emusic/Synth-diy/

for a basic module setup. these are important:
PowerSupply
-I use a power one: Digi-Key #179-2068-ND that is +-15V and 1.5A

VCOs
-ken's CGS VCO is based on a very popular design. it's a good place to start

VCFs
-lots to choose from. check my links below and the CGS35 steiner is a
nice one.

VCAs
-also lots to choose from but most people build a linear VCA. this can
be built from an operational transconductance amplifier (CA3080 or
LM13700) or discrete transistors. usually an array (CA3046). also look
in the links below.

envelope (EG)
-usually start off with some simple AD or AR envelopes, and maybe an
ADSR. normally you would build one that has an exponential decay. there
are many simple designs to build.

LFOs
-Ken's CGS utility LFO might be a good one to start. I haven't built it
but I will consider it when I start building more LFOs for my synth.
this is a simple and will get the job done.

MIDI interface
-if you want MIDI then there are a few options. Oakley
(www.oakleysound.com) has a few designs you can buy PCBs for. these are
very nice. also check out Marc Bareille's site.
(http://m.bareille.free.fr/midi.htm) he's got some PCBs for sell for
midi interfaces. both sites there have the schematic online. Oakely
usually doesn't do this but the schematics for midi interfaces there are
free.

so, i didn't list much for LFOs, EGs and VCFs. for that, and many more
modules check the links section on my site:
http://www.sdiy.org/destrukto
go through all those sites and look around. you'll get a good idea of
the options you have. I'm not sure if you meant to design the circuits
yourself, but even so, these links will help in planning out what to
design and what to build. I have decided a while back that I can't
design every circuit (not enough time) so I'm building from PCBs for
most generic modules and designing ones that don't exist yet or things
that aren't so cheap.

-ryan

t0ny_mowbray wrote:
Show quoted textHide quoted text
>
> Hi,
>
> I used to have a Korg PolySix and a mono (can't remember the model)
> with 1/4" jacks over it. Unfortunately I sold them both and now I am
> kicking myself!
>
> I want to build a systh from scratch and I really need some help to
> point me in the right direction. I am an Electrician and I have
> Electronic trades on top. I am a licenced amateur radio operator
> (VK2AGM) and I probably have the skills necessary to do it all (my
> soldering iron is my friend...). I have also worked in the computer
> industry since Intel created the 8080 uP.
>
> Any help woul dbe most appreciated. Thanks in advance.

Re: Starting from scratch

2005-02-19 by t0ny_mowbray

--- In cgs_synth@yahoogroups.com, "t0ny_mowbray" <tmowbray@i...> wrote:
Show quoted textHide quoted text
>
> Hi,
>
> I used to have a Korg PolySix and a mono (can't remember the model)
> with 1/4" jacks over it. Unfortunately I sold them both and now I am
> kicking myself!
>
> I want to build a systh from scratch and I really need some help to
> point me in the right direction. I am an Electrician and I have
> Electronic trades on top. I am a licenced amateur radio operator
> (VK2AGM) and I probably have the skills necessary to do it all (my
> soldering iron is my friend...). I have also worked in the computer
> industry since Intel created the 8080 uP.
>
> Any help woul dbe most appreciated. Thanks in advance.

Well, thanks to everyone who responded. You have provided some good
information and I need to do some more research before I commit to any
one project.

I have a feeling that I "need" a PolySynth as I am a keyboard player
so I will probably look at option around this.

Again thanks.

Re: Starting from scratch

2005-02-20 by Dave Kendall

on 19/2/05 11:40 pm, t0ny_mowbray at tmowbray@... wrote:


I have a feeling that I "need" a PolySynth as I am a keyboard player
so I will probably look at option around this.



There are a few MIDI-CV converters that are polyphonic. Oakley sound
<http://www.oakleysound.com/polydac.htm> do a 4-channel module, with
velocity out CV for each note, as well as the usual 1V/octave, and 8 other
controllers (including sustain - very useful for a keyboard player) They are
currently discontinued, but it says on the website that they may reconsider
if there's interest. It looks to be a very high-spec board.

The Paia MIDI2CV8 <http://www.paia.com/midi2cv.htm> will do 2 note poly with
velocity Pitch wheel + mod wheel, or 4 notes of just 1V/octave + gate.

The Midibox CV <http://www.ucapps.de/midibox_cv.html> will do up to 8 note
poly! There may be more work involving programming, although I think the
basic midibox CV can be built off the shelf, if you order a pre-burned PIC
from one of the 2 pcb suppliers mentioned on the site. uCapps.de is also a
very cool site for DIY midi controllers.
<http://www.mikes-elektronikseite.de/midiseite.htm>
<http://avi.dezines.com/mbhp/>


If you've got loads of money, Doepfer make a pre-assembled 24 output midi to
CV. Looks like a good unit.

There are probably others I haven't found, and there are definitely some
schemos around for boards that connect to a PC. The ones I've seen require
you to write your own code.

I'm planning to build a 4-note poly synth based on the oakley or midibox
units. The biggest problem will be fitting all the boards in. For a
moderately complex 2 oscillator, 4-note polysynth, that could be over 40
pcbs! (with a big PSU as well!)

Cheers,

Dave.



[Non-text portions of this message have been removed]

Re: Starting from scratch

2005-02-20 by Richard Brewster

The Synthesis Technology MOTM-650 4-Channel MIDI-CV converter is about
to go into production. Check it out:

http://www.synthtech.com/new_stuff.html

-Richard Brewster

Dave Kendall wrote:
Show quoted textHide quoted text
>on 19/2/05 11:40 pm, t0ny_mowbray at tmowbray@... wrote:
>
>
>I have a feeling that I "need" a PolySynth as I am a keyboard player
>so I will probably look at option around this.
>
>
>
>There are a few MIDI-CV converters that are polyphonic. Oakley sound
><http://www.oakleysound.com/polydac.htm> do a 4-channel module, with
>velocity out CV for each note, as well as the usual 1V/octave, and 8 other
>controllers (including sustain - very useful for a keyboard player) They are
>currently discontinued, but it says on the website that they may reconsider
>if there's interest. It looks to be a very high-spec board.
>
>The Paia MIDI2CV8 <http://www.paia.com/midi2cv.htm> will do 2 note poly with
>velocity Pitch wheel + mod wheel, or 4 notes of just 1V/octave + gate.
>
>The Midibox CV <http://www.ucapps.de/midibox_cv.html> will do up to 8 note
>poly! There may be more work involving programming, although I think the
>basic midibox CV can be built off the shelf, if you order a pre-burned PIC
>from one of the 2 pcb suppliers mentioned on the site. uCapps.de is also a
>very cool site for DIY midi controllers.
><http://www.mikes-elektronikseite.de/midiseite.htm>
><http://avi.dezines.com/mbhp/>
>
>
>If you've got loads of money, Doepfer make a pre-assembled 24 output midi to
>CV. Looks like a good unit.
>
>There are probably others I haven't found, and there are definitely some
>schemos around for boards that connect to a PC. The ones I've seen require
>you to write your own code.
>
>I'm planning to build a 4-note poly synth based on the oakley or midibox
>units. The biggest problem will be fitting all the boards in. For a
>moderately complex 2 oscillator, 4-note polysynth, that could be over 40
>pcbs! (with a big PSU as well!)
>
>Cheers,
>
>Dave.
>
>
>
>[Non-text portions of this message have been removed]
>
>
>
>
>See the following URLS for the CGS Modular Synth home page:
>Main: http://www.cgs.synth.net/
>Secondary: http://otherunicorn.0catch.com/synth/
>Yahoo! Groups Links
>
>
>
>
>
>
>
>
>
>

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