Thank you for the kind works. Pretty happy with the woodwork myself. It says a lot about the ingenuity of the original mini front panel design to see it work so well in negative colors. This is just inkjet paper on acrylic, it was much cheaper to do it this way, and print black on white, than to get...

I decided to call it a day and close her up. She's fully functional and sounds right. Time to make some music!

I checked and saw the same shapes as you discribed. Here is a little demo of how my instrument actually sounds, just 5 sounds including a short FM FX thing in the end: https://www.youtube.com/watch?v=9u3dSwrqKPk It does sound lush and gorgeous, asymmetrical waveforms or not... Can't wait to put min...

Gorgeous build, Troubleshooter :hail: Thanks, about your 3 problems: I wouldn't care much about the unsymetrical waveform neither would I worry about the shape after the filter. If the results sound fine it's OK. Changing the resistor as you suggested is also the best solution for your scaling prob...

Gorgeous build, Troubleshooter

Hoping someone still reads this thread, here's 3 issues I still have with my crowminius 1. All 3 square waves are asymmetrical, being 47-53%. All components surrounding the LM393Ns are correct. Is this normal? If not, what could be the issue? 2. The output signal looks very different on scope than t...

Gorgeous!

JanneI wrote:Ok, I think I found the problem. R194&R195 should be 8.2ohm and I have 8k2. Oops

Yes, that was it! I didn't find 8.2ohm so I used 10ohm. Still much closer than 8k2

Glad to see you figured it out!

SMD stuffed PCB and a front panel is fine for me, especially if the through hole parts are easy to source!

So happy to see this is happening. And from a fellow Belgian to boot.

Finished mine a few weeks ago and finally got round to take some pics.

Enclosure made from an Ikea bamboo cutting board.

sonicblue99, I used these from Mouser. They are solder lug but they have pin versions as well.
http://www.mouser.be/Search/ProductDeta ... 2511F-26RN

JanneI - do you have a clean +/-10V from the PSU?

evengravy wrote:Are the parts that can be left off the PCB in this case (MIDI DAC Parts) listed somewhere? The MCU and DAC are pretty obvious but resistors etc. I'm not sure.

The only useful thing I can tell you is that if you want the 440 reference tone, you'll have to populate the Atmega section anyway.

How are you powering the synth? Looks like getting a good +/-10V should be your highest priority now. Also, SW8 and SW10 require a DPDT switch, you can use SP for all the other switches. It has been quiet here lately, I hope Crow hasn't forgot about us mortals here. First thing - did you measure the...

Things seem a bit quiet here lately so I don't expect much help, but I'm still gonna post this for the off-shot that someone here reads this and can help me. I've finally finished assembly but I don't get any sound from the synth itself. I get the test-tone on all outputs, all LEDs seem to work (ex...

Glad to see this finally became a reality!

Two questions : 1. I can't seem to get enough base voltage to tune OSC2, I run out of turns on the ZERO trimmer to get it up high enough to be in tune with the other two oscillators, with the OSC2 FREQ pot in the middle. I got it to scale across all octaves, but the Frequency knob is set to about +1...

Finally figured out the problem yesterday. I doubt anyone will encounter the same issue, but I'll share for historic purposes. When I first started to populate the board, I solder the through-hole tempcos flat on the board. When I figured out they needed to touch the 3046s, it seems I had some desol...

And another one : the front panel of the original Oberheim SEM!

What I got from a guy from Banzai is that Hongh (or HongYu) was started by some ex-Alpha employees or engineers. Their English website : http://en.hongh.com/index.html Looking at the datasheets, they are pretty much identical to their Alpha counterparts. The Alphas are still cheaper at Tayda, but th...

SynthOSphere wrote:Instead of what?

Instead of single turn trimmers, which would probably be a real PITA to calibrate the oscillators with.

If anyone has an idea where to start looking, any help would be greatly appreciated. Transistors have correct orientation, btw. I tested the power supply yesterday and I get a good +/-10V. Tried to start the calibration process today, but it appears OSC1&3 are dead. OSC2 has sound and responds to ra...

(apologies in advance if I'm the only one excited by this minor revelation :miley: ) nearing the business end of my build, and I'm not sure if the tip is useful or not, but I used plastic washers under my pots, which seemed to space them almost perfectly with the adjusted vertical mount pots -and e...

I tested the power supply yesterday and I get a good +/-10V. Tried to start the calibration process today, but it appears OSC1&3 are dead. OSC2 has sound and responds to range, freq and waveform changes, as well as the PWM. Checked all switches and connections, and they look good. Swapped out the IC...

Perfect, thanks! That was the last puzzle piece for me. To disable the pitch wheel, you want to "lock" a DC voltage into the pitch wheel node of the CV input summing amp. The easiest way is to just use a couple of 10K resistors where the pot would go, one from CW to center, and one from CCW to cente...