MiniMoog VCF Clone

MarcoVella · Joined: Apr 05, 2011 Posts: 11 Location: Australia

Hi There

My name is Marco I am currently studying audio engineering at SAE institute, I at the moment am about to finish my degree and for my final project I wish to build Yusynth's famous MiniMoog VCF clone.

I have only done basic electronic circuitry before such as electric guitars and re-wiring guitar pedals (real easy stuff).

Though I am in desperate need of some help, not necessarily how to do the whole project but what things are and why/how things work.

If you could help me answer the following questions it would be significantly appreciated:

1. What exactly is 1 V/Oct tracking and in the easiest translation possible, how would one go about doing this?

2. How would one go about Adjusting T3 in order to reach auto-oscillation near 95% of the full range of the EMPHASIS pot? What does this mean the underlined section mean?

3. What equipment would be needed to complete V/Octave tracking such as,

* Apply 0.000V to the V/Oct input
* Turn the frequency knob fully counter-clockwise in order to measure 0mV at the base of Q1 (node between R9 to R11)
* Apply 1.000V to the V/Oct input
* Adjust T1 in order to measure 18.2mV at the base of Q1
* Apply 5.000V to the V/Oct input
* Check that you have 91.0mVat the base of Q1, if not adjust T1
* Apply 0.000V to the V/Oct input
* Set the filter to auto-oscillation (EMPHASIS turned fully clockwise)
* Connect a keyboard (CV/GATE) to the V/Oct input
* Play a tune and check the goodness of the tracking
* Slightly adjust T1 to achieve a good chromatic tracking.

4. Does the MiniMoog VCF need a power supply? (I'm not quite sure how this works, in terms of full electronic/circuitry terminology etc).

5. Is there a certain procedure I have to follow in terms of signal flow? eg, soldering capacitors first, then later resistors or should i start from my IC's first etc?

I apologize for how stupid I may seem but this is an area of work that is quite fresh for me, though it is an area work I find extremely interesting, and something I wish to put full focus towards.

If someone could reply within the next few days it would be much appreciated.

Thanks again guys,

Marco Vella

yusynth · Joined: Nov 24, 2005 Posts: 1314 Location: France

MarcoVella · Joined: Apr 05, 2011 Posts: 11 Location: Australia

Thanks for your rapid reply!

1.
So in order for me to apply octave tracking how would I do it, what would it involve? Trim pot adjustments or is there more to it? I understand now what it means i just do not know how to apply it?

2. So technically this would just involve me adjusting the trim pot 3? Is there anything else to it?

3. So in order to adjust the voltage tracking etc, i will need to have a digital multimeter to measure the the voltage, and a digital tuner to adjust or will using the trim pots be the only thing to adjust to retrieve good voltage tracking? I'm still a little confused by how I would go about doing this sorry! Smile

4. So I understand that on the schematic there is a section created which will be the power supply (dock), but will i need an actual power chord, if so what one should i purchase in order for this to work efficiently, or will the power connection would be one like a guitar pedal?

Finally, I'm sorry for seeming like an absolute dumb ass, but I think it is most important for me to understand a lot of the concepts before proceeding with the project, I hope you can answer my questions and that they make sense to you! I know i may seem like I don't know enough at the moment to start this project, but i am still eager to learn everything needed to do so.

Also what other equipment would i need to complete this project, eg, soldering, etc?

Thanks again, you've been a great help!