hello today we're going to be looking at
the forant analog symphasis forant
analog Sypher so a little bit over a
year ago now I did a video on the forant
DIY analog synthesizer as part of the
DIY synthesizer series to which I've
covered a fair few already and there is
a link to a playlist below well the
forant DIY project came out in elector
magazine starting in May 1977 and it
gave you all of the information on how
to build your very own DIY analog
synthesizer there is a link in the
description of a PDF file of the full
part one series of the elector forant if
you haven't watched the first video that
I've done on the elector forant maybe
check that out first because it will
give you more of an insight into the
history and the project itself but in
this video we're going to build upon
what we found out in the last one by
making a bigger and better forance a
couple of weeks after I put that video
up I got contacted by Steve Clark who
had a spare box full of loose forant
modules of completely unknown condition
which I ended up purchasing from Steve
they got shipped over from Germany and I
had a a good old rummage around there
was a fair few modules in this box
including a few filters oscillators
various envelope generators and voltage
controlled amplifiers as well as
numerous unbuilt pcbs and panels
regrettably for the last year this box
has been sitting on a shelf and I really
hate having unfinished projects sitting
around it makes me feel all weird inside
so in this video we're going to make a
change to that the elector formant that
I covered in the last video I've got to
be honest was a bit of a basket case of
a synthesizer that's the thing about
buying a DIY synthesizer the quality
always varies from Project to project
that's because one of them could have
been built by somebody who knows what
they're doing and the other one could
have been built by somebody that was
very well-meaning however it turned into
a bit of a rats nest you know the
quality of DIY synthesizers is not
guaranteed and that Sy has somewhat test
my opinion of the forant and I want to
change that by getting a more realistic
experience of a forant by making a
better one basically the other forant is
not completely set up to how it is
described in the magazines the thing is
the foran isn't actually a modular Sy
sythesizer no no no it's a semi modular
synthesizer yes it's supposed to be
intended to be set up like a COR ms10 or
corg ms20 the idea is that there is a
default setup for the sympathizer you
have no patches in all of those Jack
holes and you play the sympathizer
twiddle and knobs it's going to make
some noise that's because there is a
default way the synthesizer is routed so
the oscillators get mixed together then
they go into the filters and then that
goes into the voltage controlled
amplifier and so on but once you start
putting Jacks into the different sockets
you're able to kind of re-root things
and change the synthesizer from the
default settings this varies from other
Combi synthesizers of the time for
instance the mini Moog it hasn't got
different routing possibilities except
for what is available on the knobs and
switches the old format however was on
the other side of the spectrum it was
set up in a completely modular way that
means around the back the only things
that were actually connected together in
the synthesizer modules was the power
and this is a very similar setup to most
urx synthesizers as well as DIY
synthesizers like the digisound 80 as
well as my Cosmos synthesizer these are
fully modular synthesizers that means
none of the modules are talking to each
other until you start putting cables
Here There and Everywhere this made the
form that I have not a great synthesizer
because it wasn't originally intended as
a fully modular synthesizer so not all
of the parameters are actually available
on Jack sockets and it somewhat limits
the possibilities that were originally
intended for the synthesizer I spoke
about it in the previous video like it
wasn't a problem but since I've come to
use to synthesize a more I've realized
it's quite a downfall for the machine
the problem is making it pre patched
around the back makes the whole build
quite a bit more complicated and we're
going to find out why and how in this
video there's also some extra videos
samples and songs made with this for and
synthesizer available on my patreon
which is down below which helps support
these silly projects right here anyway
enough chatting let's talk about the
build I started by bashing a case
together I did this in a similar way
I've built other synthesizer cases
that's with some cut to size plywood
panels for the top and the sides I
merely glued and screwed them together
then used another bit of Timber in the
middle to separate the two module
shelves and a few even thinner bits of
wood to screw the modules into oh yeah
and this this is it oh lovely trly
woohoo so this case is big enough to fit
12 of the big modules on the bottom and
12 of the little modules on the top I
have more forant than this can fit
however the plan is is to get this
working and then figure out uh making
another case on top uh at a later date
now we have the case we need to figure
out how to put the Power connector
chunky bits around the back so we've got
this vco we're going to start with the
voltage controlled oscillator I think
we're going to have one over here first
we're going to screw that in and we're
going to use this to measure out
everything around the back I don't know
how obvious this is but from the back uh
this connector is exactly the same
height in the case as that connector
over there and it is exactly the same
depth going back so with this in mind we
need to make a kind of metal connector
chassis that goes all the way over here
that we can connect all of the
connectors together so then they all
have their designated spots then we wire
all of the designated wires to the back
of this F goop and it should be done bit
b bash how we do that is a bit of a
mystery as of right now I've got these
aluminium extrudes and we're going to
use this I think uh we're going to cut
it to size so it fits inside and then
we're going to bolt these to some wood
or something and then we can bolt this
to that and should be all
[Music]
right yeah I think this is going to work
right so that's going to sit right right
up here pop that right there Precision
Engineering you'll see that I've drawn
where the metal seems to sit so what
we're going to do is get a bit of wood
that kind of sits
here sore an earring right here nearly I
just got sand off the top and it's all
right oh oh yeah bit of the old Gorilla
Glue used the clamp and everything
beautiful oh yeah beautiful right so now
put those bits of wood on the back as as
well as ones on for the top rows as well
because there's a top row and they've
got the same power connectors so we're
just going to let the glue dry I'm going
to give this a bit of a paint a bit of a
wood stain and we're going to get we're
going to get going with
it now the case has been sufficiently
cified we can start building the
synthesizer into it we're going to start
by putting the metal bars in we're going
to screw these onto these metal plates
so they're ain't going to go nowhere and
then after that we can start putting in
the connectors I was doing this by eye
so this was the first one I was going to
add some supports to this but it's
actually quite sturdy so it doesn't need
it um then I took out some extra modules
from the older rat nest foran because
we're going to add to it and you'll
notice that they they're shorter how
annoying is that uh so I didn't think
about this but if you look closely
you'll see that these mounts are
actually handmade they've been cut up so
luckily in this box that Steven had
there was some of the official ones uh
sitting in the bottom so I managed to uh
put some of these on these first modules
which made them the same length as the
rest of them so they would actually line
up with the back connectors and then I
drilled some holes put some more
connectors in for each of them and bit
by bit One By One The oscillators were
being put in place and they fitted
nicely to the connectors so this is the
third oscillator after fiddling with it
a bit this next one is a filter it's a
24db filter you can see it's the same
length but it's a different size and the
rest of it goes on the top as well so
these all going quite straightforwards
you just pop them in kind of figure out
where the connectors go drill the holes
pop the connectors in and hope for the
best basically and yeah bit by bit uh it
started to come together I didn't have
enough of those official mounts so some
of them had to be put in with spaces and
standoffs because they were all
different lefts it was quite a hodge
podge but it came out all right in the
end uh this is a random module I'm not
even sure what it is it's on stripboard
but I thought it was too cool to not put
in anyway and then next to that a ring
modulator which is also a short circuit
board that is not going to have a
connector connected to it this is for
the power and also the keyboard
connector we'll look at that in a little
bit this is going to go and connect in
the back so we can connect the keyboard
into it and then there's this very small
strip board for the power for all of the
things that don't actually have their
own mounts and connectors on those metal
rails now we've got a wire in the power
to the back of the connectors this isn't
as straightforward as you might think
because every single module uh the power
is on a different pin uh I I know it's a
bit odd but whatever so we had to figure
out where the power goes the plus 15
Vols the minus 15 volts the ground and
then the oscill is also have a 5vt line
as well now all that's plumbed in we can
see if all of these modules actually
[Music]
work so this oscillator worked but the
one next to it didn't and I couldn't
figure out why until I found out that
there was actual power connectors uh at
various points on the actual pin
connectors which didn't make sense but
after I fixed that then it started
working but this potentiometer was broke
so I had to swap it out and then
finally we have
[Laughter]
life success bit by
bit it was at this point a package
arrived from jvr Foreman I didn't
realize until doing some research
recently that jvr actually makes brand
new Foreman modules I bought this off
him he only sells assembled modules no
PCB kits but he offers reproductions of
most of the foran modules with a more
modern PCB around the back I went for a
sequencer to add some more depth to this
[Music]
synthesizer now we got to fill the rest
of the syn case so we're going to take
the other modules out of the older one
because we don't need that case anymore
because it's a right hodge podge uh
these all still needed modifying to
actually fit with the normal uh forance
sizes and some of the wires actually
needed extending because it was extended
longer than the original designed forant
that that was bodged to there's some
dates in there 1981 this was built and
then refurbished in 1991 there's a
picture of the spacer on this one there
were all different spacers because all
of them were like Hodge pods together
this is the envelope generators for the
other side of the sympathizer because
we're going to make a stereo syn this
com is the output it's got a equalizer
base metal treble and some volume and
also some lights to show you that all of
the power is working as it should uh
we're going to put this in at the end
because that's the output for the
synthesizer now we're going to make an
aesthetic effort by uh changing the
knobs to all of the matching knobs I
didn't have enough so I got some spray
paint and sprayed these white knobs uh a
kind of funky gray to make it fit uh the
best one I found was Ford Dove gray to
make it it look the same color as your
granddad's for CA anyway they match
pretty well as you can see I'm I'm
pretty happy with
[Music]
that
[Music]
I was so pleased with how the spraying
the knobs turned out I decided to spray
the knobs of the sequencer as well
because as you saw they were not
matching at all they were fancy and
black ones let's make them into these
weird gray things anyway uh we're going
to start fixing the keyboard well at
least looking and seeing what's wrong
with it I mean I haven't even tested
this yet so we'll just scope out what's
going on underneath you'll see that it
is controlled by these Springs and a lot
of them kind of were not fitting very
well and they were all kind of like
caught on different bits but this is
premonition because you'll see it's
going to bite Us in the eyes later on uh
yeah I changed the connector which is
not a midi connector it is actually just
the connections for the voltage from the
keyboard to the syn after I tested the
connections were right it was time to
add this little circuit board into the
module box itself it's a buffer for the
keyboard so it goes on the other side of
the wire and kind of standardizes the
voltage from the keyboard apparently it
can run without this but this is a good
measure to avoid abnormalities ooh very
fancy after that we're going to test it
you can see the lights flashing now for
the keyboard Gates and then yeah it's
buffering that and then I tuned it to be
Vault per octave this synthesizes vult
per octave so you hit a c and you hit a
higher C and you try and get it as close
to a volt difference between each of the
C's as you possibly can as you can see
that's pretty much a volt in each octave
after that I was pretty confident that
the keyboard was going to work we were
going to have to start iring all of the
wires into the back of the synthesizer
this yellow wire goes from the gate
output of that buffer circuit board that
is buffering the keyboard and that wires
into the inputs of the envelope
generators then this pink wire is the
control voltage out of the keyboard and
that wires into the back of the
oscillators to give the tune as you can
hear right
now it's
working oh not for long
ah uhoh yeah you know that earlier about
those Springs well it turns out they are
very easy to kind of flick onto each
other and get
stuck but now it's starting to
[Music]
work the voltage of the keyboard also
goes into the filter you see that ecv
kov switch if you flick that to keyboard
output voltage you can actually get it
to control the filter with the keyboard
as
well make it sound like
robots now the keyboard's working and
all the voltages are internally wired to
the modules from the back we can look at
this image from the magazine which shows
you where all of the connectors around
the back are supposed to go the next
thing we're going to wire in is the
output of the signal the audio out of
the oscillators into the input of the
filter so these purple wires that I'm
putting in are wired to the pins of the
output from the back of the oscillators
and then they're wiring into the inputs
on the VCF so you can see there the
purple ones right
[Music]
there that was the first time we heard
all of the oscillators going in into the
filter because there's a mixer around
the back so that's why we can hear them
all a lot of the twisty knobs were wired
in backwards it's a DIY syn what do you
expect so I wired them around the right
way after that uh this oscillator also
didn't work because it's a switched Jack
when there's no Jack wired in then it
goes into internal routing mode but it
wasn't working but now it works as you
can hear so have a listen here's
two and free
baby
now for the rest of the internal wiring
the output of the adsr into the voltage
input of the VCF and the voltage output
of the adsr into the voltage input of
the VCA but the signal output of the VCF
needs to go into the audio input of the
VCA but then the audio output of the VCA
needs to go into the
rfm it says it all in the magazine if
you want to read it more then the link
is below to what I'm reading here it's
just a layout but it gets a bit
complicated because some of the pcbs
have labels and then the unofficial pcbs
well they have no labels at all which
doesn't help when the pins are all over
the place it seems and there's no
standardization between modules but
anyway I got there in the end so I did
all this wiring that I just described
and I'm I'm running out of breath
already this is a lot of talking I got
to be honest but yeah after this we've
nearly have a fully fledged S Voice so
let's let's have a listen shall
[Music]
we
[Music]
[Laughter]
[Music]
the oscillators all needed a little bit
of calibrating but surprisingly not much
at all they were already out of the box
pretty in
[Music]
tune
[Applause]
[Music]
you may think we're done but you're
completely wrong we got to finish the
rest of the synthesizer so we're going
to put some more modules in this side I
went for exactly the same style of syn
voice over here so we've got two of them
that are going to make different sounds
at the same time you'll find out how
magical that sounds later in the video
but as you can see uh yeah this one uh
there was a few problems I needed to
swap a few things like this switch which
was broken and then I popped it in and
then after wiring all of the wires again
to the back but on this side it's
exactly the same setup as before uh we
can test
[Applause]
these I wasn't as lucky with this side
it took a fair bit of trying to get
these to somewhat work especially this
volage controlled filter which just
wasn't working for no reason I swapped a
bunch of capacitors and chips and stuff
reading the schematic which which made
it helpful but it was only until I
compared it to the working one from the
other side of the synthesizer I noticed
that this dualed transistor package was
wired in upside down and that'll explain
it there's another thing to be said
about repairing DIY synthesizers even
though you get a pleora of documentation
and descriptions on how the circuits
work and things like that unless you've
spoken to the builder of the kit you can
never assume that it actually worked in
the first place and an example of that
is this filter module it would have
never worked because the transistors
were upside down there was signs of the
Builder trying to figure out why it
didn't work because there was a few
different resistor values here and there
which I ended up having to put back to
normal because the problem wasn't
actually fixed keep that in mind because
you might have to be looking a little
bit closer than you were expecting to
give it a snip oh come on what's with
all the blunt pliers yeah we're getting
really close to the end now it was at
this time where I decided to do a bit of
wax lacing to clean it all up a bit so
we got this wiggly wiggly wiggly around
the back twist that and just poke this
through that pull the whole thing
through slowly kind of find where you
want it to be it takes quite a bit of
practice to get it to the right length
and then tug it that way uh and then you
just do the same again so I'm going to
do it like I did actually that's a
different that's an easier way of doing
it so twist pop it in the hole pop it in
the hoop and
then then we got that and then um find
where you want it to be
roughly and then pull it give it a good
tug I like Wax Laing it looks a lot
neater in my opinion than cable tires
that's why I went for that anyway after
that it was nearly done we added this
mixer to the output module because
there's two synthesizers now that needed
mixing together and it's
[Laughter]
[Music]
done
[Music]
I forgot to mention I added two output
jacks on the side so as far as this
video is concerned it is done there are
still a few little jobs here and there
to do uh one of the lfos here doesn't
work the one in the middle it's not
lighting up this oscillator's got
something weird going on and I haven't
quite got to the bottom of it yet and
this oscillator isn't even assembled but
apart from that it should all be working
so let's get it plugged in and see what
it can do okay I'm an absolute bliing
idiot I don't know how I did this I lend
it over and on the corner of the
keyboard I managed to snap off the uh
the switches of this brand new sequencer
bluming thing I'm going to have to
contact them and see if I can get a link
to The Replacements or buy some
Replacements that is so annoying luckily
they're not massively important right
now but what a pain in the bottom anyway
so it's set up like a dual synthesizer
this means that there are two separate
synthesizers running in parallel this is
the same as a synthesizer like the cs15
Yamaha cs15 where there's two separate
synthesizers they've got an oscillator a
filter envelope generators and vcas two
of them so they run in parallel so you
get two separate s sounds at the same
time albeit being controlled by the same
note because it's still monophonic right
now they're both being wide via that
mixer that we added around the back of
the com so they're going in and coming
out in a mono form in a second we're
going to do a stereo thing let's listen
to only this synthesizer first and it
already sounds like a 1980s electr pop
Banger oh baba baba turn on the rfm the
resonant frequency
monkey sort of like a resonant
[Music]
EQ
[Music]
oh my God this godamn keyboard it's
already
stuck I've got a spring
stuck oh what a pain in the dairy air
right one set I got one do this that's
why these Springs get a bit too excited
with themselves and they end up just
popping back up here there's loads of
them that have done it what an annoying
design oh yeah I forgot we can adjust
the
base and the
mid oh that's the volume and the treble
oh
[Music]
nice nice there's a bit of uh crackling
turn this one down and turn up this
simple siiz of
voice which right now I must add is only
a single oscillator because this one's
decided to play up there's something
seriously up with that one and this
one's not even built so we've got a
single oscillated one here so double
triple and a single but it's it's it's
enough to get going so we'll get a
nice we'll get a slower thing going oh
no and then turn this one back
[Music]
up oh no oh God damn it this freaking
keyboard no you're joking oh that this
Gan keyboard's going to be oh my gosh
it's got a fair bit of Chunk to
[Music]
it now okay let's uh I've left it long
enough let's get some patch cables on
the Go okie dokie so we're going to
start
patching we get a single patch cable
going here and doing all the stuff a
control voltage input modulation input
uh from this oscillator right
[Music]
here right let's get the uh LFO coming
out of here into the clock input of the
uh sequencer get that coming out of the
uh voltage output into the voltage input
of this
oscillator
[Music]
so now via these cables over here both
of these are coming out of separate
outputs uh right now left and right
slightly panned so we got
the got the left and right
[Music]
oh yeah going have to modify it to
actually get it to um talk to the
keyboard and the gate at the same time
that's a bit annoying it's a bit of an
oversight with this uh machine is
there's no external gate input in the
design initially so uh it's just
keyboard right now and the keyboard's
absolutely
[Music]
rubbish
[Music]
the thing that really stands out with
this one with its setup right now is
it's actually pretty damn chunky
sounding I don't know whether that's the
correct definition but in the next one
when we finally have six oscillators and
the modified external gate and keyboard
inputs and extra things I don't know
when that'll happen but I really think
this synthesizer might be a force to be
reckoned with and if you've noticed
there's only two patch cables in it
right now in fact like I've been
perfectly happy just fiddling around
with it with its internal patching it's
really
[Music]
nice
oh oh
[Music]
yeah
[Music]
[Laughter]
wow that's pluming awesome actually that
sounds really cool it's like two
synthesizers in one but it's got a real
fat sound to it get a little bit of um
LFO into this
filter and then a little bit of LFO from
the other LFO into this
[Music]
filter
[Music]
I really like this I wasn't expecting to
really like it I mean when I've got over
the fact that the keyboard's a bit of a
mish mosh this is really cool I haven't
even used the external sequences and
stuff well we've used the sequencer a
little bit but it just sounds really
good get some more lfos on the go all
right let's add this to the
[Music]
CV oh yeah see the fact is this actually
has six lfos in it Al be one of them
isn't working right now but it really
means you could just plug in random lfos
into random
[Music]
Malak
oh the wobbles The Wiggles the wobblies
random voltage out of the noise plug
that into external CV we'll get the
external CV plugged into it that means
it's not going
[Music]
to
the sequencer as well and we're going to
sequence it's all going to be going on
now flick it over from the keyboard
control I
think there we
[Music]
go one back
up
it's going crazy now
[Music]
um there's a lot to focus on that's
pretty mad I've really need to get more
into this I want to fix this I want to
fix these two oscillators I'll do this
in a subsequent video and we'll get more
out of it then and then hopefully maybe
in that same video there'll be another
case which will have another I've still
got another four oscillators a bunch of
adsr and VCA so there's enough to get a
whole other syn voice so that'll be free
simp voices uh all controlled by the
same notes and stuff so you get the same
kind of texturization from the foran
it's pretty cool it's really interesting
to build it as it was intended because
it makes you use it completely
differently you save all of the patch
cables not just for getting the bug
standard synth route and you end up
using it all for modulation like I've
done right
here there's a lot to focus on isn't
there how cool is
that for this video because it's getting
quite long this is the end of the road
but there's going to be another part
after this hopefully it won't take as
long as the last time I've included a
direct recording of all the sounds and
Rifts and stuff you can chop them up and
use them as you will and like and
they're over on P patreon so if you want
to use them for things and stuff and
support making these machines and these
videos then go and check it out over
there there's a bunch of other videos on
that I did a bunch of videos whilst this
was going up including outter wax lace
and stuff like that so that's over on
patreon supports all of this stuff and
the museum that this is going to go into
because by all means come and play on
this it will be able to be played in at
this Museum's not obsolete the link is
below uh with a load of other DIY
sympathizers and things like that there
might be a weekend I don't know which
one it'll be gone again because I'm
going to try and build it and improve it
and fix it and stuff but for now if you
want to play on it come over to this
Museum's not obsolete anyway I hope you
learned something today I'm look my no
computer this is the foran sythesizer if
you like what you see don't forget to
subscribe and don't be scared to try
don't be scared to try maybe don't sit
here and cry for a soam for a
[Music]
[Applause]
week
[Music]
n