starting to learn things

textbased · Joined: Apr 09, 2006 Posts: 6 Location: chicago

hey
i decided i want to build a synth. i wonder if anyone here knows of some good reading or tips to help me get started. like, what you think i should build first, or a link to online parts suppliers
i have been looking for schematics for a VCO with at least a square and sine output. i should start small you know? but i have big dreams.

one time i made a contact microphone

i really appreciate any kind of suggestions
thanks a lot!
d

Uncle Krunkus · Posted: Sun Apr 16, 2006 7:21 am Post subject:

Hey Textbased,
Welcome to electro-music.com! Smile

I'd start by reading as many related posts as you can on this forum. Definately visit Ray's site: http://www.musicfromouterspace.com/
And ask as many questions as you like, there is always someone here ready to impart whatever knowledge we have.
Have fun!
Andrew

textbased · Joined: Apr 09, 2006 Posts: 6 Location: chicago

thanks a lot, that was exactly what i was looking for
who is ray?
thanks ray.
thanks andrew.

bigtex · Posted: Sun Apr 16, 2006 11:28 am Post subject:

Also, if you ever want to go beyond kits and pre-planned circuits, you'll want to learn a little electronics theory.

Check out The Art of Electronics, which is probably the best electronics book ever. That site is only about the book... you'll have to buy it to get the text. But there are plenty of free resources online.

Good luck! I just started on down the same road myself. My circuit boards from Ray just arrived!

Uncle Krunkus · Posted: Sun Apr 16, 2006 3:43 pm Post subject:

Ray Wilson is the dude behind Music From Outer Space.
He's a bit of a celebrity round here (not least of all for his online comedy show!) He designed the Soundlab. He drops in to this forum from time to time (adhdboy I think) Try doing a search for all his posts if you've finished scouring the MFOS site.

piedwagtail · Posted: Mon Apr 17, 2006 6:44 am Post subject:

Having spent the last year building....i'd recommend reading first.

Then build a Power Supply (+)15-0-(-)15 @2A a side...about a 75VA transformer.If you are considering making your own PCBs,this is an ideal time to venture into etching.The PSU can be drawn out by an special ink pen onto copper clad board and then etched.I personally love etching probably because it is chemistry and so unlike music or electronics(gives one a break from the usual obsessions!).A small bench drill will be needed for drilling the holes.
Buy a decent soldering iron,temp controlled 24V would be best,skimping isn't worth the time you'll waste.The psu will get your head round transferring schematics to materials.
Bring the 15-0-15 out to screwable banana posts.This will then enable you to test everything you build subsequently by just attaching free wires into the psu.

Then i'd suggest building a decent LFO,because a slow moving waveform is so useful for testing so many things ie.vco cv,vcf cv,vca cv etc.
Then as your momentum and confidence increases and needing to see the LFO working you'll need a scope.Simple analog scope like the old Tektronix 5000 series is fine.But any
reputable,reliable 1 Mhz scope will do for synth work.Ebay is a good source.

So you'll probably be thinking....bench drill,quality iron,scope.....that's all expensive.
The answer is going halfway is not going at all,and you'll be having enough problems with taking your learning to practice without dealing with shoddy tools.It pays off!

Robert

Uncle Krunkus · Posted: Mon Apr 17, 2006 8:00 am Post subject:

If you're short on cash.
Nice bench drill, yeah.
Quality soldering station, yeah.
Scope,.... well it's a nice luxury. But not essential. I've been doing DIY electronics for 20yrs or so and still haven't gotten around to getting one.
Don't get me wrong, it is a nice piece of kit to have. But if you're gonna have to go without any of the three, that would be the one.

mosc · Posted: Mon Apr 17, 2006 8:36 am Post subject:

You can use your PC as a scope for audio waveforms (check out Visual Analyser http://www.sillanumsoft.com/ , but soundcards aren't DC coupled so for DC you can use a digital multimeter. So, I agree with Uncle.

Still, a good scope is a joy on the bench. But you should get a multimeter first anyway. There are lots of times you'd want to take measurements and a scope isn't handy, and it's hard to measure currents and resistance with a scope.

zipzap · Posted: Mon Apr 17, 2006 9:32 am Post subject:

Hi there
For quite some time i didn´t even have a multimeeter. Didn´t want to spend any money.
As soon as i realized that my little circuits really work i got one. never want to be without.
My startingpoint was this little distortion. Not rally synththing, but audio. Super simple, build it on perfboard so no etching. Just hook up your guitar, mic or cdplayer.
http://www.runoffgroove.com/multiface.html
check the indexsite for more and also:
http://www.generalguitargadgets.com/richardo/perfboard/index.html

That was a good start because it worked right away and got me hooked up ever since! These are also nice and easy:
http://www.geocities.com/tpe123/folkurban/fuzz/snippets.html#lofomofo
Another thing you could get is one of those solderless experimental boards. Makes things fun and easy.
These are all things that do something by themselves. Next thing could be a SIMPLE (square) vco (doesn´t have to be super v/oct tempstable stuff),
a lfo as mentioned and some vcf. there´s your first synth.

piedwagtail · Posted: Mon Apr 17, 2006 1:14 pm Post subject:

knew that scope insert would be contentious.....

I built valve amps without one,and started with synth circuits blind.
But i think the reckoning was when i checked the Thomas Henry 3080 vcas and watched the input attenuated under cv adjustment,that was when i realized this was ok.I can do this:gave me a lot of confidence.
Now that i'm playing with cmos composition,it would be hard without.

When i bought my DVM it was $50 8 years ago ,my latest scope was $80 off evilbay.
For the aspirers....if you're not ever considering RF then there is a lot out there secondhand.
Plus everyone comes round your gaffe and says"Wow,is that an oscilloscope?
Wink

zipzap · Posted: Mon Apr 17, 2006 1:28 pm Post subject:

Just got my scope from evilb for 30 bucks - and its broken...
Checking an vca-adsr combination, thats exactly where i would like to see whats going on. With CMOS you´re saying you don´t want to miss it. why?
It´s only logic, right? So isn´t it quite predictable anyhow?

piedwagtail · Posted: Mon Apr 17, 2006 2:21 pm Post subject:

Well yes it's high or low......
but it's when is it high or low?

i'm just through self-boarding some cgs pulse and voltage control dividers....checking them is a breeze.
plus i got into those touch switch circuits that the 70s elektor mags were full of....

My first evilbay scope smoked on switch on,it was Russian NOS but the fine seller had stored it for years in his damp basement.This was only apparent without the hood.
The Tek 5111 was lovely but gradually diminshed itself,probably psu caps: my love of electronics does not extend into wanting to repair scopes.A nice man drove half of england to pick it up to do just that!
So now my third Kenwood with the infamous faint trace is doing fine....

Hope my travails help without your disappointment

Smile

Robert

mosc · Posted: Mon Apr 17, 2006 2:33 pm Post subject:

I used to use one of those small logic probes. They have LEDs that change colors for logic high and low. They sometimes beat a scope because you don't have to take your eyes of the circuit. Years ago they were pretty cheap. I would guess that is the same nowadays.

zipzap · Posted: Mon Apr 17, 2006 2:39 pm Post subject:

hey robert, we´ve got the same name
Shure, i´d like to know where my squarepulse went sometimes...
Those touch swiches, what do they do? I was thinking of some triggersequencer with just one row of swiches for eg 6 channels. So it would need some storing and logic and stuff to play the drums. No microcontroller, i never touched one of those...
Is that the kind of thing those old electors were full off?

Poor textbased, 9 posts about getting started and now this.
How do you build a contact microphone? Is it like the piezo thing you put on acoustic instrumnents?

zipzap · Posted: Mon Apr 17, 2006 2:41 pm Post subject:

NOrmaly i just hook a lc-led via an 2k resistor to the cmos output i want to monitor. As long as its no medical equipment nothing bad should happen. Problem is when things go fast

piedwagtail · Posted: Mon Apr 17, 2006 2:48 pm Post subject:

yes we're spoilt for choice....
but i did like the idea of putting a solidstate scope into the modular,to check as patching... Posted Image, might have been reduced in size. Click Image to view fullscreen.

Posted Image, might have been reduced in size. Click Image to view fullscreen.

[/img]
ten rows of ten segment leds for the matrix...

zipzap · Posted: Mon Apr 17, 2006 2:54 pm Post subject:

i want to build a sequencer out of this... 100 pots instead of the leds...
then hook a noise sorce to it

Uncle Krunkus · Posted: Mon Apr 17, 2006 4:55 pm Post subject:

I've got this really cool little clip which sits on top of any chip. It has 16 leds on the back which tell you the logic state of every pin. Takes it's power off the chip. Super simple, very handy for CMOS. I think it came out of the mid 80s when there were still heaps of discrete logic chips in the Telecom system. (A friend gave it to me in the 90s as it was already mostly irrelevant) I think it was standard issue in the early electronic exchanges.

textbased · Joined: Apr 09, 2006 Posts: 6 Location: chicago

zipzap: that is exactly what a contact microphone is
here is how to build one: http://home.earthlink.net/~erinys/contactmic.html

is a perfboard the same as a breadboard?

thanks for the good advice and links. lofomofo on geocities has me stoked, and also Ray's 'weird sound generator' looks like a project thats going to happen very soon. maybe not so soon i'll see how it goes and let you know

zipzap · Posted: Fri Apr 21, 2006 1:04 am Post subject:

bugbrand · Posted: Fri Apr 21, 2006 1:53 am Post subject:

On the subject of contact mics::::

They are super simple to make and are supremely useful & interesting for recording / experimenting. Over the last few years I've churned out 1000+ of them at low price for people who wouldn't get round to building them themselves.. They've been really popular - sent to all corners of the world.

That article on how to make them is a good start point -- but its strange, in the US you don't seem to be able to easily find the raw piezos (only encased in plastic cases) -- over here in UK you can either get uncased piezos with wires from Maplin (order YU87 - about £0.39) or completely raw piezos from JPR (cheaper but you have to buy about 600 of them to make the £30 minimum order!)

You get a MUCH better signal if you replace the pre-attached wires - carefully desolder and then replace with a short (15cm or so) piece of standard (not too thick) screened audio cable and attach a 1/4" jack SOCKET to the other end.

I've always covered the top with a layer of epoxy resin too -- not only does this really strength the mic (the connections of the wire onto the piezo are otherwise really weak and break off in no time) and it also slightly dampens the high freqs which gives a better sound.

GREAT THINGS!

blue hell · Posted: Fri Apr 21, 2006 11:43 am Post subject:

textbased · Joined: Apr 09, 2006 Posts: 6 Location: chicago

ok. i have only heard "stripeboards" been called "breadboards."
heh

mosc · Posted: Fri Apr 21, 2006 7:26 pm Post subject:

Breadboards - the term - goes all the way back to the beginning of electronics, I understand. People in the very early days would build tube circuits on pieces of wood. These were called breadboards. I guess people even used real breadboards.

At Bell Labs there was a story. In the company stockroom, they would supply people with really nice wooden boards for use in building circuits. They were pretty loose in the early days so people could go to the stockroom day after day and get stuff. One day a fellow had a party and invited his mates from the Labs, including his director. Apparently the director went up to see the shop in the attic and discovered it was paneled in Bell Labs breadboards. Shocked

The story goes that the fellow was fired.

Anyhow, I think the term breadboard now means a prototype no matter what type of circuit wiring techniques are used. I've even heard people use it to describe a prototype program - proof of concept type thing.

Uncle Krunkus · Posted: Sat Apr 22, 2006 3:33 am Post subject:

I originally knew breadboards as the ones which have commoned holes which you push wires into temporarily. When Scott said that his DimC was still on breadboards I realised that he must mean something else. There are so many proprietory names for what is basically a piece insulator with holes in it.