Building a new bass / melody / lead synth

Skrog Productions

Hello , i'm constantly running out of space on my diy modular Smile

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Over the years using the modular i have a common monosynth patch up i regularly use in my music , my idea is to build a hardwired synth using those modules from the main system and house them on a new panel & wooden box , thus freeing up space for more modules in the blue wardrobe.

Here is a rough diagram of what i have in mind.

To be operated as .....
2 separate monosynths.
A 2 vco 24dB monosynth.
A 2 vco 12dB svvcf monosynth.
Parallel & series vcf combinations via multi-pole switches.

Once ive built the wooden box and sourced a alum sheet 600mm X 250mm , the project will gather pace Smile

Dave.

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Wobuse · Joined: Dec 07, 2011 Posts: 34 Location: Lyons,il

That's a kool idea Wink

You should look on eBay for a broken organ perhaps .
You could reuse its keyboards & PSU.. Rework the front panel to acomidate those modules.Maybe pick up sum retro styling ,along the way.
A random example http://www.ebay.com/itm/VINTAGE-RETRO-ZENTA-ORGAN-/221233638547?pt=UK_MusicalInstr_Keyboard_RL&hash=item33828d6c93

...and another...
http://www.ebay.com/itm/VINTAGE-WURLITZER-MODEL-101-MLM-MUSIC-LEARNING-MODULE-ELECTRIC-ORGAN-Needs-TLC-/321126944906?pt=Keyboards_MIDI&hash=item4ac4a8508a
Keep in mind ; you don't have to stack keyboard manuals to have a dual system. You could split the buss for a side by side approach . Hit one side with a colored lauqer ,then.Or cut out two octaves..move those up top & put a face plate where the octaves where. cyclops

Make a modulation wheel from a lawn mower wheel. So many possibilitys !

Skrog Productions · Posted: Sun Jun 02, 2013 4:56 am Post subject:

thanks

It would be nice to do a full keyboard but i need it to fit under 2 modular cases in a corner, so it has to be a sloped front, wedge shaped sound module only.
thanks for the links tho.

Dave.

Skrog Productions · Posted: Sun Jun 02, 2013 9:34 am Post subject:

Been in the shed......

I sketched out the design of plywood box to fit in the small space under the ASM-2 synth, then into the shed armed with saw , measuring tape , set square & straight edge & pencil ,pva wood glue , bag of 1" brads / panel pins & hammer. Oh , and nice plywood off cuts from a work skip Smile

.

After a couple of swearing incidents and a tea break and this is what i hacked together today.

Dave.

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elmegil · Posted: Sun Jun 02, 2013 6:10 pm Post subject:

Are you very short? I'm just trying to figure out how you got footprints inside the box!

Wink

Skrog Productions · Posted: Mon Jun 03, 2013 12:00 pm Post subject:

My Nord micro mod. done a protest dance in the box when i wasn't looking Wink

Skrog Productions · Posted: Sat Jul 06, 2013 10:06 am Post subject:

Hullo , got the box painted with a few coats of dark grey , now ready to bond the wood fixing rails for top & bottom panel support.

Dave.

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Skrog Productions · Posted: Sat Jul 06, 2013 10:26 am Post subject:

Here is my first draught of my layout for the front panel , i've got it to fit to 250mm high by 500mm wide on 3mm aluminium sheet , leaving a single module space to the right when the panel fits to the box , which is 603mm long inside.

Most of the parts of this synth will come from my main modular , so it's mainly a re- panel / re-wire job with a few extra pcbs to build in the modulation area.

To fill the space on the top right im thinking of using an multi-FX pedal and a distortion / overdrive with ken stone stompbox circuits on veroboard.

I'm going to let this layout simmer for a few weeks until i get an offcut of alum panel from a metal fabricator/engineers workshop.

i've spent a few days with the modulation sources for all the CV attenuators , making sure they are evened out over the destinations, i hope i've covered all my usual patch configurations with this layout Smile

Dave.

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Skrog Productions · Posted: Sat Jul 06, 2013 10:34 am Post subject:

Not sure which colour of vinyl will go with the dark grey, hmmm Smile

Dave.

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PHOBoS · Posted: Sat Jul 06, 2013 10:41 am Post subject:

purple, will go nice with the color of the casket and with your blue modular. or go crazy and make it neon pink Twisted Evil

Skrog Productions · Posted: Sat Jul 06, 2013 10:47 am Post subject:

pink panther Smile

Skrog Productions · Posted: Sat Jul 06, 2013 10:50 am Post subject:

yes , i like the lilac / purple colour , but the orange is super easy to read the text , but i'll learn it real quick , looking like purple if the print shop has some Smile

Dave.

PHOBoS · Posted: Sat Jul 06, 2013 11:24 am Post subject: Pink Panther Bass Panel

Skrog Productions · Posted: Sat Jul 06, 2013 11:50 am Post subject:

Fantastic , heh , thanks Phobos Smile

Skrog Productions · Posted: Sun Jul 14, 2013 7:30 am Post subject:

Hi ,
The 6 lfo's i have made on veroboard are from Ray's site under the oldies but goodies section , six of the "variable skew lfo" which outputs 3 main waves... sine / ramp - tri - saw (skew) / square.

I have made a few veroboard circuits and i now just follow the diagram and populate and isolate as i go and give it a good continuity test afterwards before the "no chip" power up test.

I have also started to the mfos micro S & H circuit which will have the lockhart wave folder & dividers on the same strip.

more in a week or so Smile

Dave.

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ashleym · Joined: Aug 20, 2009 Posts: 181 Location: uk

Sorry to be late on this.

What filters are you going to use? I like a variation from the standard LPF. A SVF or a combined LP/HP such as the MOTM CS80, Ian Fritz Threeler? I have a CGS CMOS or Wasp style filter on the drawing board. Mine will have dual-concentric pots to control two filters from one(ish) set of controls. I got these from Small Bear.

Skrog Productions · Posted: Fri Sep 06, 2013 9:56 am Post subject:

Hi Ashleym

I have a mfos lowpass for vcf1 and a mfos state variable for vcf2 that are to be taken from the modular Smile

.

cool , dual pots is a good idea , hope to see pics of your twin vcf your building / planning.

On my filter section, im going for a toggle switch to choose between normal independant vcf CV control or vcf1 CV in sum to vcf2 cv in, so they can both be sweeped from vcf1 cutoff dial. (whooooosh! sounds and more Smile

)

Dave.

Skrog Productions · Posted: Fri Sep 06, 2013 10:21 am Post subject:

Im slowly taking my time with this build , heh , ive rearranged the panel layout a bit to fit the FX i wanted on the panel, which is now 600mm long Wink

, still in the final stage of "what can i put in that space" , i was thinking vc-panner or a externally clocked melodic/random trigger generator of some sort for the 4 ADSR's. Hmmm.

Dave.

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PHOBoS · Posted: Fri Sep 06, 2013 10:30 am Post subject:

Skrog Productions · Posted: Fri Sep 06, 2013 10:39 am Post subject:

Hi Phobos , yes it's in there , hiding on vco2 and a lockhart wavefolder on vco1 , wavey Smile

PHOBoS · Posted: Fri Sep 06, 2013 11:01 am Post subject:

ah, I didn't look at the panel, just at the first block diagram. good Smile

if you can get a CD4089 you could make something nice with that.
(here's an example)

ashleym · Joined: Aug 20, 2009 Posts: 181 Location: uk

[/img]
This is just a screen shot of my Shaeffer design. On the left is the Wasp filter. The small circles are for the dual-concentric knobs, below switches for filter type then the banana sockets. I colour co-ordinate; blue for in and yellow for out so I dont need to add any labels. The small and larger circles are to show which part of the control is for which or the 2 filters. I try to eliminate writing and use signs and colours to define functions. I need to work on some graphic icons to add to the layout to reduce the writing even more. Something as corny as a graphic for an envelope of an envelope!!

I hope this helps. or at least explains.

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ashleym · Joined: Aug 20, 2009 Posts: 181 Location: uk

Here is the dual pot link. I got some from Small Bear, qiick and efficient.

http://www.smallbearelec.com/servlet/Detail?no=1213

Skrog Productions · Posted: Wed Sep 11, 2013 10:13 am Post subject:

Hi Ash

Nice blue panel Very Happy

, i like blue Wink

Mad idea.... ignore this if you have finalised the design...... a double pole switch to swap one of the filters sweep direction on the dual pot , half way turn on the dual pot would be the cross-over point of the 2 filters sweeps.

Dave.

Skrog Productions · Posted: Wed Sep 11, 2013 10:26 am Post subject:

I was scanning over the layout and it dawned on me i'd forgotten glide/ portamento on the vco's , fixed now Smile

, i've considered a few circuits for the space at the right end of the panel and i think im drawn to ken stones burst generator circuit for a bit of spicey trigger action on the ADSR's & probly through an attenuator to the vco cv in's as well.

Finish the panel design , then off to the print shop up town for a black n white drill template sticker and the finishing final 250mm x 600mm lilac / purple vinyl sticker with black text lazered on.

Dave.