Thursday, August 5, 2010

x0xi0 #330-133.5 : Custom I/O Power Supply

Despite the documentation being in development I went ahead and started building the PSU of the custom PCB. The key step in even this first task was preparation time. Reading through the forum threads, some of Brian's emails and notes, and cross checking the original parts list with the x0xio parts list were all part of the lead up to just get this in place. I also created a separate version of the original parts list that flags all the omitted and replacement components. When these come up I'll then know to reference to the x0xio list for further instructions. I've posted it to download here as a temporary measure.

All in all the actual build steps were quite similar to the original x0xb0x but as you can see from the photo there are some changes that need to be made. For one, there is the additional 12V supply in place that handles the mods' requirements. Secondly there's the need to keep this I/O low profile since the mod board will be stacked above it. Third, as far as I can tell there needs to be some space under the voltage regulators to slide in the heat sinks. You can see how there's just enough space there for between the regulators and the PCB. Fourth, like the mod boards, some spots are tight. You can see how my two capacitors, C7 & C8, are slightly angled. They're just a little wide for one another there. I had to set them properly ahead of time so they don't land into place with extreme angles.

Little details like these will be all too easy to miss. On the one hand it's probably smartest to wait for the install manual. Brian's existing manuals are very clear in that respect. On the other hand I couldn't bear having this kit sit in pieces here for any longer. I had to see some action and move forward. The next step is to sort the parts properly for each section and do that dirty work up front. That should make catching unique details a little easier.

Thursday, July 8, 2010

x0xi0 #330-133.5 : Top Panel 'Full Kit' Mod

It took about 3.5 hours to pull the top panel together. Like the I/O mod, the steps were relatively simple. Brian has laid the documentation out in a pretty straightforward way. Three components were missing: one 103k capacitor and two 22K resistors. A quick trip to Supremetronic sorted that out.

There isn't really any testing or calibration one can do until it's wired up to a power supply and x0xb0x so there will certainly be more work to follow once the new x0x is built. I'm hopeful that everything is in order here. It looks absolutely amazing. Dropping the top panel on there gives a quick glimpse of the power of this ├╝ber 303.

Friday, June 11, 2010

x0xi0 #330-133.5 : I/O Mod Board

Now that 99% of my parts were here I couldn't resist and got started on the new build. I spent the first while organizing some of the parts (especially the resistors), reviewing the documentation, and taking notes on some of the support issues a few builders have a come across. At the moment it's a bit of a sea of confusion in some areas but the I/O and Full mod are well documented. The custom PCBs for the main x0x, not so much. Brian suggested I get started on the mod boards first so I took the advice when it was given :)

Generally speaking it was a relatively painless task but a few things cropped up. I've made a habit of socketing ICs and transistors but the layout and spacing for some of these parts doesn't really allow it without making very specific cuts and sizes on the sockets. Working on the I/O was a good introduction for what's to come. In future I'll need to try surrounding parts and see if it even fits. Some of the transistors are also not set up in a linear configuration so a basic socket strip that's been cut won't work. The BC547B has been set up this way. That's a bit disappointing but again, at least now I know that this is the case. Since I'm using the custom PCBs the power supply is being installed there and being left blank and omitted here.

So all in all ~ this build needs one's utmost attention!

Tuesday, June 8, 2010

x0xi0 #330-133.5 : Step Zero

In fall of 2009 I started to get the itch to take another run at a new x0x build. My intent was to build 2 or three of these anyway so Brian Castro's x0xio kit was the right fit: it's more complex, expands the x0x's capabilities, and still retains the original clone's accuracy in the process. He also produced a first run of custom PCBs in April 2010 specifically for his mod so I'm among the first five or so builders putting it together. Needless to say I'm an early adopter on this one! As such the documentation is still incomplete. I'll need to tread carefully so I don't botch up the project. My kit arrived at the beginning of June. It was a patient wait but well worth it.

Goals for this project

Just the x0xio kit. The main board an I/O are equally large as the spread in my self-sourced build.
My goals are somewhat similar to my self-sourced x0xb0x. I still want to maintain some control over the final cost. I managed to avoid several suppliers by using reliable alternatives: James from Willzyx, the new x0x supplier taking over for Adafruit, Brian, the source of the mod itself, and my local electronics supplier. I'm also able to spread some of the costs from my original self-sourced x0x since I purchased parts for multiple units at that time. This project is primarily based on BOM v2.1 and a dizzying list of mod parts from the x0xio site. I'm less concerned about the hours spent this time around, though I may choose to keep tabs on it.

The serial number

Between my self sourced x0x and this modded one, I also came across an incomplete original run x0xb0x, number #330. It needed repairs, testing, and the like. I was able to get it back up and running with a fair bit fussing around. I decided that #330 could be used as the core for this build. The x0xio is dramatically different but I think it'll be worthwhile to have key parts of the original kit be used here. This way its roots are still planted in adafruit territory. So the number represents #330, #133 of the x0xio kit, and number 5 for the custom PCB set.

Monday, June 7, 2010

x0xb0x SS#01: Finished

Better late than never! The finished x0xb0x, SS#01. I never did take the time to snap that last photo and wrap this up but here it is.

With all the experimenting one can do with a project like this, I have to admit that it was difficult to simply close it up and consider it done. Time and time again I would open it back up, try something new, and tweak it some more. Despite the long lag in posts here it has served my set up really well by being a go-between of all sorts. I've been using it practically daily since my last post. Midi in and thru has been used in full force, with Ableton Live serving as the Master to all the gear and the x0x slaving a Jupiter 6. The CV/ Gate has proven itself worthy controlling a modded MC-202. Finally DinSync, of course, has properly connected the 202 and a TR-606 to the whole rig. So , all in all, this is an extremely useful instrument and tool. The 303 cloning is perfect and the I/O it has on hand bridges the old gear with the new beautifully.

Did I meet my goals?

In one of my first posts I set out a plan for this project:

- Keep the hard costs as close to zero as possible,
- source as many of the parts locally and from within Canada,
- minimize (or at least be aware of) hidden costs,
- document time and cost.

Hard costs:
I'd say I came out ahead in some areas and lost out *a bit* on others. The grand total for *this instrument* came down to about $475.00 CDN when factoring in rare parts end to end (including a $50 BA662A), some custom features like the Korg EMX-1 TB-303 style silver knobs, puchasing from multiple sources, shipping from all of these sources, and duty fees in some cases, and hidden costs. In some cases it was only advantageous to make a larger quantity purchase to justify the shipping. This means building multiple x0xes to spread out the cost. I would say I embellished in some spots to get the sound just right and that increased the cost.

Parts from Canada:
If I only I knew then what I know now! Since the start of this project I have found other sources in Canada that significantly help control cost. I largely used sources based on the BOM that was provided by the x0xb0x community but I now know that many components can be had here for more or less the same price and I can cycle of drive to the store that sells them. My next project, as you'll soon find out, already begins utilizing these sources.

It's interesting to see how wildly prices fluctuate between suppliers. A basic component like a resistor costs $0.09 US each from Mouser. I can get the same carbon resistor locally for $0.02 and a 1% metal film resistor for $0.05. It doesn't seem like much but when you need hundreds of them and factor in shipping and duty this is a significant difference. One can rationalize this purchase by lumping it in with items like pots and encoders and what have you to justify a one supplier purchase, but if cost is important, as it was for me, it's worth watching carefully. My original pruchase from Futurelec helped tremendously. I picked up enough 1% metal film resistors (and other bits and bobs) from them for three units at a cost of $0.02 each.

Minimize hidden costs:
This is where one can bloat and kill a budget. Shipping here and there for this and that, duty (which you can't control), the odd trip for another part, and experiments with another component types. Before you know it you blew another $100. If you click-and-shipped your way through this maybe it's $150-$200. It's so easy to blow that extra cash and then marvel about how you got a 303 for $350. But did you? Nope. Not at all. Not even close. Look at the numbers and it'll tell a different story.

I think I did minimize these hidden costs to a degree. I didn't avoid them but I did minimize it as best as I could given that this was my first crack at it and I was aware that it was part of my goal. As I mentioned above I now know that I can do better in this area but I think I did okay.

Document time and cost:
Grand total: $475.00 for this unit and if I factored in my time at an hourly rate add on another $10,000.00 :D This is a very involved project. If I was in the business of electronics I suppose I could bang this out much faster but cine I was learning it took loads of time and preparation. The caveat with that $475.00 is that I've got enough components to build two more. If I don't pursue that (hint, hint) then the cost is significantly more.

What did I learn?

First of all I learned that I love the 303 more than I did before! This project is well worth going through, not only to have yourself a prefect 303 but to also learn about the inner-workings of a legendary intstrument like this. It's pretty cool to crack open a real 303 and understand what it's doing. For that reason alone I'd recommend it to anyone who's into synths and is prepared to open one up and look at it up close.

Secondly I've learned that I need to be patient. As soon as I got impatient I made mistakes, some of which cost me more money and time. Having said that, I may have been too patient in other areas of this project. A year and half to wrap up the synth and blog is too long. In reality it could have been completed in much less time, real life interruptions notwithstanding.

Finally I learned that I'm capable. I suppose it's like any area of interest, as soon as one gets a little bit knowledge in a new subject a whole world opens up and new possibilities become apparent. Despite the lag on this project's time line, I did make time to work on other synths in between since I had no fear of opening them up and seeing what was going on with them. The more vintage gear one has, the more it becomes a necessity to maintain it all. If you have deep pockets by all means take it to a pro. Quite often though the repair can be fairly simple, so projects like this x0xb0x begin to educate us gear heads.