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In the 1970s, the first personal computers did not seem to be very important.  Arguably, it took far more time and energy to get them to do something than was ever saved by using them.  Nonetheless, tinkerers all over the place talked about how important they were going to be. 

By the mid-1980s, they actually started being useful, and by the 1990s, they had begun transforming our lives.  Secretarial pools, travel agents, newspaper classified ads, and letters sent through postal mail have largely become anacronisms, and the technology has changed almost every area of our life.

But when we look at popular technologies that have come along since, they have been evolutionary, not revolutionary, despite what the ads say.  iPods, iPhones and iPads have just made some functions of personal computers available when you are not in front of a traditional computer.

But this week I got to play with a technology I believe may be truly transformative.  The device in question is called a 3D printer.  Calling it a printer is a bit misleading.  It creates three dimensional objects, in the case of the one I played with, out of ABS plastic, from a 3D model downloaded to it from a computer. 

Professional 3D printers exist, but they are expensive.  They start somewhere around $25-$30K.  But some NYC hackers created a kit to build one for less than $1000, popularly known as a MakerBot (the actual name is the Cupcake; MakerBot Industries is the name of their company), and they’ve been selling out each production run months ahead of time for the last year.  That’s what I got to play with.  You can see an object I printed below:

 MakerBot CS logo

The triangle is the actual object, the logo of Crash Space,
a hackerspace in Los Angeles. The frame underneath is
called a “raft” and is there to prevent curling as it cools.
The raft is peeled off and discarded.

The Cupcake is a machine you do a fair amount of futzing with in order to get it tuned in perfectly.  Once you do that, it runs well, but getting there can take a bit of work.  And the parts it creates sometimes are less polished than ones molded in a factory.  But if the technology evolves over the next decade in any way similar to how personal computers did in the late 1970s and early 1980s, the world will be a different place.  Here’s an example:

Twelve-year-old Julie buys a new cell phone.  They ship her the guts of it (a circuit board with a display and keyboard attached), and expect her to get the case for it separately.  She looks online, and finds a design she likes.  She edits the design, adding her name and a butterfly embossed on it.  She pays a license fee for the design, and then either prints out the case on the family 3D printer,  or goes to Ginko’s Copy Shop and has them print it for her.  She prints it in bright pink plastic that matches her room. 

Meanwhile, a fitting has broken on the dishwasher.  Her father dowloads the part data from the appliance manufacturer’s website and prints out the part.  Julie’s birthday party is the following weekend, and her mother prints out personalized party favors for the party shaped like butterflies (Julie likes butterflies). 

Does this sound fantastic?  Well, a MakerBot 3D printer was used about a month ago to create a replacement part for a dishwasher, though the manufacturer did not have a 3D model or even the plans available online.  At least for MakerBot tinkerers, this vision of the future is already becoming a reality.

I’m currently designing brackets to mount my cell phone and iPod in the car, which I’m hoping to print out soon (yes, I do know how geeky this sounds).  Meanwhile, the MakerBot folks announced the successor to the Cupcake this week, called the Think-O-Matic.  It can print slightly larger objects, has more accuracy, and has a small conveyor belt to move completed objects off the printing surface, so printing the next object can continue uninterrupted.  If you are interested in learning more, you can read their press release or watch a MakerBot in action.  Get ready for the future, here it comes!




Preamp Heaven

Musicans and audio people tend to go through a progression.  First they are fascinated with musical instruments.  Next they are fascinated with microphones.  But eventually they become fascinated with preamps.  It sounds like it should be a very minor accessory, something like a cup holder on an SUV, but over time one comes to realize that the preamp may be the determining factor in how your music sounds, whether you are playing live or recording, or just building a great stereo system.

A confusing array of preamps are available running from under $100 to many thousands of dollars.  The factor I was really looking for in a preamp (which many musicians look for) is referred to as “warmth”.  This is an imperfection (referred to by engineers as a “nonlinearity”) that was common in early tube-based audio equipment.  This imperfection tended to make louder sounds harmonically richer (adding even-order harmonics), and made them be less different in volume from the quieter sounds.  Eventually, engineers built chips (called operational amplifiers) that did not have this imperfection (our engineer would say they are perfectly linear), but when people heard the new perfect sound, it did not please them.  They said it was “cold” and lacking the warmth of tubes. 

This led to a fetish for vintage equipment from the era before the new chips started being used.  But equipment does not have to be vintage to have the warmth that makes it pleasing to the ear.  It also does not have to have tubes in order to have warmth.  There is a type of transistor called a FET (field effect transistor) that has a similar nonlinearity to what preamp tubes have.  With all this in mind, I decided to create my perfect preamp.

This week I built the first model for actual use.  There were lots of prototypes over the last year, and I created a couple of different printed circuit boards along the way.  The preamp has two channels, and each channel has three stages.  The first stage has a FET transistor, the second stage has tone controls, mimicking those on a Fender Twin Reverb guitar amplifier, and the third stage is a gain stage that uses one of those operational amplifier chips, which will perfectly reproduce the warm sound of the FETs.

Below are pictures of the preamp.  I have used it with my Chapman Stick, electronic keyboards, and a Taylor acoustic guitar (with a mic and a piezo pickup) with good results on all of them.

Preamp Front

Gloster Preamp Open

Gloster Preamp Circuit Board

The New Famine

Today we are facing an economic famine.  Not a shortage of food, but instead a shortage of credit in exactly those parts of the economy that can drive a recovery. 

Consumers have had their credit cards cancelled or the interest rates on them greatly increased.  Small businesses find it impossible to get lines of credit to expand.  And homeowners, despite efforts by the government, cannot get their homes refinanced.  This has caused consumer spending, small business expansion and the housing market to stagnate.  Economists tell us that these are the areas of the economy that need to heat up if we are to have a robust recovery. 

Admittedly, in the past (particularly in the housing market) we extended credit to people who were not credit worthy.  I’m not arguing we should go back to that policy, but today we are denying many consumers, small businesses and homeowners who are creditworthy the credit they need to expand our economy.

Amartya Sen was awarded the Nobel prize in Economics for his work showing that there has never been a food famine in a democracy.  He found that when governments are accountable to the people, they find a way to avoid famine, even when terrible events occur.

Let’s take as an example the great Irish potato famine in the mid 1800s.  During the famine, Ireland grew enough potatoes to feed all of its people.  But the landowners, responding to market forces, exported most of the potato crop.  Other countries had the money to buy the potatoes, while farmers, wiped out by the blight, did not.  History tells us that if the government had been accountable to the Irish people (Ireland was ruled by Britain at the time and had no representation), the government would have found a way to buy potatoes from the landowners and get them to the people who were starving.  The landowners were not evil; they were just running their operation as a business.

In a similar way, the banks today are not evil; they are just responding to market forces and running their businesses.  But while they can borrow money from the government for no or almost no interest, for a variety of reasons (some of them our stricter banking standards), it is better for them, from a business perspective, to put that money into very safe investments.

We need our government to do what it would do in a food famine, to find a way to move resources, in this case credit, to the areas that are starving.  Unlike a stimulus that peters out once the money is spent, this credit can create a sustainable recovery.  And if the government is unwilling or unable to do that, we need to hold them accountable, just as we would if there were a food famine.  Perhaps then, we can look forward to a day when we can say no economic famine ever occurs in a democracy.

Over the last few years hackerspaces have sprung up all over the U.S.  These are places where members chip in some money every month to rent a space and stock it with exotic tools and projects.  The members tend to have an eclectic mix of technical skills.  Often in any group of 5 you will find experience in writing computer programs, digital circuit design, analog circuit design, mechanical design, use of tools like CNC mills and laser cutter/etchers, art school, user interface design, musicianship, rocketry and building exotic radio equipment.  Plus a love of science fiction, comic books and techno music.  Whenever I encounter a hackerspace, I have the sense that I have found my tribe.

A local hackerspace in the Los Angeles area that is particularly active (there are a couple more around town) is called Crash Space.  I visited them a few times and joined their email list.  When I went to a meeting about a month ago, the club had just been selected to participate in the VIMBY/Scion Hackerspace Challenge.  Several hackerspaces around the country were given $3,000 each and asked to build something cool with it over the course of a couple of weeks.  Though I am not a member of Crash Space (yet, anyway), they let me be part of the team.

The project they decided to do was to put an array of ultrasonic sensors along the front of the storefront that is Crash Space.  As people walked in front of the building, they triggered the various sensors, which triggered different noise making devices, many of them consisting of a relay driving a “thwacker” that banged a bottle or flower pot.  There was even an “Easter Egg”, where if you ran back and forth the entire length of the building several times, it would start playing the Close Encounters 5-note signature tune (you know, Boo-boo-boo-bowww-boooo). 

I built a stereo audio mixer with phantom power for the project, wired up ultrasonic sensors and helped to assemble the thwackers.  You can see pictures of the unveiling here:

 On a personal note, if you look at the 11th picture in the series, you can see the mixer I built on the lower level, just to the right of the Memory Man.

 Anyway, the sponsors are VIMBY, a competitor to YouTube, and Scion, the car company.  A videographer filmed the entire process, and there will be a video of it at some point on the VIMBY site.  And some of that footage will make its way into a Scion car commercial after that.  Also, they will choose a winner from among the hackerspaces who competed.  We are up against the legendary NYC Resistor hackerspace (in New York City).  But all that is in the future.  For now, it was great to be part of such an interesting and (to their neighbors) unbelievably cryptic project.