Synthesis Technology's Tutorial Page

Welcome to the Tutorial Page. Here, we will try to help the newbie kit builders, as well as provide additional information about the MOTM synthesizer and analog circuit design.

Tutorial #1 is provided by Bernie Hutchins of Electronotes. It is a "white paper" on the merits of sine wave generation by software and DSPs. It is provided in Adobe PDF format, the same as our data sheets. If you don't have Version 3, please download it from the CEM data sheet page. Tutorial #2 is a "Getting Started" essay.

If you have any comments on this, or suggested topics for future tutorials, please email us at the address below.

Tutorial #1: Digital Sine Wave Generation

UPDATED! Tutorial #2: Getting Started in the Synth DIY World

A commonly asked question is "I'm interested in building synthesizer circuits, but I'm not technical. How do I start?" Hopefully this will give you some good ideas and tips. This is no means the definitive method: everybody learns at different levels.

Where do I begin?

• What is my current skill level in electronics?
• What is my goal? What do I hope to accomplish?
• How much money and time do I really have?

It has been my experience that all hardware projects take twice as long as expected to finish, and all software projects 4 times as long. Maybe that's just me, but others will probably verify this. The reason is that at the start, we are excited. But as time drags on, and things don't turn out as planned, frustration sets in.

Having said all that, let's get going. The most important thing to me is DO YOUR HOMEWORK! by this I mean read up as much as you can. I started out as a chemistry major. That is, until I saw a ARP2600 at a music store. Kiss the periodic table goodbye! So I learned from scratch starting at age 20, and interest in synthesizers carried me to a MSEE, 10 patents, and a new career.

Here is a list of books EVERYBODY should own, or at least read

• "Vintage Synthesizers" by Mark Vail. Very good description of all those antiques we love!
• "Electric Sound" by Joel Chadabe. Interviews with over 150 synth pioneers. Love the picture of Laurie Spiegel on pg.161: it looks like she's sticking her hand into a exploded Moog. Also great photo on pg. 245 of a Serge with a patchcord stuck in every jack. Warning: sort of wanders from topic to topic. But great reading. Great pictures.
• "Electronotes" & "Preferred Circuits Collection" by Bernie Hutchins. The little monthly newsletter that launched 100s of EEs. The definitive DIY circuit & theory collection. Still in publication, although more DSP based. I suggest buying the "Collection" first. If you like it, save your money and get the entire set (about 2500 pages, I guess!) Bernie is at 1 Pheasant Lane, Ithaca, NY 14850
• "The Op Amp Cookbook" by Walter Jung. A classic, not extremely math based. Good active filter section.
• The DigiKey (1-800-digikey www.digikey.com) and the Mouser (1-800-346-6873 www.mouser.com) parts catalogs. In Europe, try Maplin in the UK
• Get the databooks from Linear Technology, Analog Devices, National.
• Download the Curtis and SSM datasheets off this website.
• Get Craig Anderton's books: he has 4 or 5. "MIDI Projects for Musicians", etc.
• Get Barry Klein's book

READ READ READ

What equipment do I need?

Ah, my favorite question. This is a function of your budget and space available. My rather snobbish attitude is that unless you are willing to spend at LEAST $200 on tools and such, your DIY attempts will be somewhat futile. Attacking a pcb with the incorrect soldering iron can quickly destroy a JP8 or MiniMoog. Using cheap dikes (diagonal cutters) can chew up a wiring harness. Trying to save $5 off a power supply can fry your entire Moog 55. An so on. It's MY opinion that most people start, and then STOP DIY projects because they get frustrated using the little tools they have (can't make front panels, etc).

Do you have to spend a fortune? No, you just have to spend WISELY. Again, it's a process of thinking AHEAD. So, in order of importance (and estimated cost in US$) is what you MUST HAVE:

• Good soldering iron. MUST be temperature controlled (not necessary variable). I use Weller EC1002 variable irons (about $240), but that was a Christmas present (to myself!). I used a Weller WTCPT iron with interchangable tips (tips only $5 each) for 18 YEARS (yes, the same one!). The price today is about $109 - $119. If you buy NOTHING ELSE, BUY A GOOD SOLDERING IRON!!!! You want to use 700F tips. For the WTCPT, get a PTA, a PTH, and a PTS tip (all 700F). These will provide a good range of tip sizes and shapes. The tips screw in and out in seconds.
• Buy good solder. Back in the good old days, the solder had rosin flux. This was nasty stuff. If you didn't clean the rosin off, it turned dark brown, started to absorb moisture, and short out the circuitry. Cleaning the stuff required harmful chemicals. Today, there are 2 types of flux: water cleanup and no cleanup. I prefer water cleanup for new projects, and no cleanup for repair work. I use Kester #331 0.020 diameter (water clean) and Kester #245 (no cleanup). Get 63/37 alloy (lead to tin ratio). One 1 pound spool of solder will last at least 3 years, and costs $14. Cheap!! Even though we provide solder in the kits, it doesn't hurt to have extra laying around just in case.
• Buy the best hand tools you can afford. If you plan to build more than 5 MOTM kits, you will really appreciate having good tools. There are 2 main tools you want to "splurge" on if you can: pliers and diagonal cutters. Pliers are used to bend and form wire. The specific kind you want to buy are called chain-nosed pliers with serrated tips. WHEW, that was a mouthful. Chain-nose referrs to the shape of the jaws, and the 'chain' part means 'jewelry chain'. But, that's just a generic term like 'needle-nose'. The following parts are from Techni-Tool (see the link below).
  

  668PL024 - $11.10ea
  294PL116 - $13.85ea
  

  These will last 2-3yrs just fine. Now, if you really want the good stuff:
  

  844PL891 - $50.00
  272PL861 - $28.46 (smooth jaws, but this is the pair I use every day)
  

  Diagonal cutters: easily the most important hand tool, because you will be cutting 100's of wires in the MOTM kits. So, it really pays off to get good ones! Here are some in different price ranges:
  

  758PL173 - $9.65 (OK, but will wear out sooner than others)
  294PL206 - $16.45
  217PL880 - $42.15 (these are what our techs use every day. Will last 3-4 times longer than the first 2)
  272PL522 - $49.90 (these are the ones I use every day! Wonderful cutters!)
  

• Get a 'lead bending tool' from Mouser, stock #5166-801. The best $3 you will ever spend! Forms the resistor leads to the required 0.400 inch spacing.
• Get what I call a "Solder Sucker". These are hand operated (although there are motorized ones!) vacuum pumps that really suck molten solder. They come apart for cleaning. I use a Ungar #7881 (about $26) and they last 5 years.
• Save your money, unload that synth you never play, and get a good Digital Voltmeter (DVM). Don't scrimp: buy a Fluke if you possibly can. Flukes are the brand everyone else tries to imitate. Good models are:
  

  Model 73-3, about $130 (good all-round DVM)
  Model 12B, about $100 (less accurate, but adds cap measuring)
  Model 83, about $290 (the 'standard' DVM against all others are judged)
  Model 87, about $350 (what I use, because this is the best DVM made, period)
  And of course there are others (not as good) like the B&K Precision Model 391 ($185) or Model 2408 ($50). Also, a popular 'budget' meter is the Extech MP520 ($100, with capacitance and frequency). Lastly, Radio Shack meters are good and readily available.

• Lastly, get a PanaVise. You will thank me. These are a small, table-top vise with a weighted base. They are used to hold pc boards while you solder and poke around. Get Model #350 (cost about $80). I have had my PanaVise 17 years! My wife uses it to make arts and crafts as well. Techni-tool part #620PO072.

If you see one underlying message in this list, it's this stuff lasts a LONG time. Don't view this money as short term: I view it as $50-75/year for 15 years, and well spent.

What do I build? How? What if it doesn't work?

You may have noticed I left out "test equipment" in the above list. That's so as not to scare everyone away. I always borrowed mine when I got started. But, it goes without saying that:

• An oscilloscope is the single most important piece of equipment. Look for used ones (my first was a Leader 40Mhz that I paid $80 for). In the US, there is a publication called "Nuts and Volts" that has 100s of ads for used equipment. I'm sure there are equivalents everywhere. For analog work, a 40Mhz scope is fine (avoid 20Mhz scopes). If you want to splurge, get a Tektronix scope, new or used. Stay away from HP 17xx Series scopes. A used Tek 465 or 465B is still thought of as the "perfect" analog scope (old boss used to say, "It trigger's on a gnat fart!" Which is good (I think)).
• A stable, regulated power supply for testing. I STRONGLY suggest buying a linear supply. It needs to be a "triple output" (+5, +12, -12). I like the Elpac Model WM220-1. It is fully enclosed, has long cords, and uses a 5 pin DIN (MIDI!) connector. Very low noise. About $75. But there are 1000s to chose from: just don't buy a switcher type supply (too noisy). Look at Power General and Condor supplies.

Get Craig Anderton's books, pick a project, and start! The only way to learn is by building. Practice soldering. Contact PAiA here in the US: the Fatman synth is a very popular DIY project.

Links to parts suppliers

Here are links to tool and parts suppliers:

• Techni-Tool. Our favorite tool supplier! 1-800-832-4866. Click here.
• Jensen Tools. The company that started all this tool stuff. 1-800-426-1194 Click here.
• Mouser Electronics. Great, cheap all-round parts supplier. 1-800-346-6873 Click here.
• Digi-Key. Super-fast service. A little more expensive, but quick shipping! 1-800-DIGIKEY Click here.

That's all for now. This is just the first of many articles to come. As always, please email me anytime with questions and comments!

For more info, comments, etc. please email us! synth1@airmail.net
Last update: March 2001