VAEMI Osi-Op Thru Zero Voltage Controlled Oscillator Module Instruction Manual
- June 12, 2024
- VAEMI
Table of Contents
OSi-OP Manual
INTRODUCE
Osi-OP, which we regard as an analog reflection of the new era of digital
electronic music, is an analog and voltage-controlled oscillator module. It
was designed in Eurorack format and it has a width of 14hp. The fact that it
has Thru Zero FM Input and a Waveshape Output, which can be used for morphing,
are two of the most important features of this product. From a first
impression, it may look like an oscillator that is appropriate for subtractive
synthesis; however, we actually designed it to be used for additive synthesis.
Thanks to
Thru Zero FM, this oscillator can regard oscillators with Sine Wave as analog
operators. You can even prepare your synthesizer patch without using the
classic subtractive resonant filter. The most important aspect of Thru Zero FM
is that there is no tune drift when you increase the modulation rate. For this
reason, Thru Zero attenuator (TZ FM potentiometer) can almost be used like a
filter itself. the frequency of the second oscillator acting as FM (operator)
according to the frequency of the 1st oscillator giving the fundamental
frequency; must be set in harmonic degrees of the fundamental frequency. But
at these settings the tonality can remain in and be musical. In addition to
Square, Saw, Triangle, and Square Sub oscillator outputs, it has a Sine Wave
Output, which was designed with JFET transistors and has a very low distortion
rate, and a Wave- shape Output, which was designed with Sine-Triangle and can
be used for morphing. It also has a Wave Shape Input. It is connected to this
input via the Triangle Wave circuit board inside. Sine Wave is fixed on Wave
Shape but you can forward it to the other WS Input by patching other
waveforms, and you can morph between two waveforms. The pulse width of the
Square Wave can be adjusted. The same knob is the morphing knob of the
Waveshape Output. Since the oscillator has tempco, there is a 1V/OCT
calibrated CV Input that is sensitive to heat. It can perfectly stay in tune
up to 3.5 octaves. In addition, for FM, there are two separate CV Inputs,
Exponential and Thru Zero. While Exponential FM CV Input can take all types of
DC and AC voltages, Thru Zero FM CV Input can only be used for AC audio rate
signals. Also, when you enter a waveform on Thru Zero FM CV Input, oscillators
are soft-synced automatically. With 1V/OCT CV Input, you can adjust the
frequency of the oscillator; and with Exponential FM CV Input, you can easily
add an LFO or Envelope Generator. Square Wave Sub OSC Output, which is
completely synced with fundamental frequency and can give an octave lower than
the fundamental, will help you a lot to create strong modern synth-bass
sounds. It is made with NOS IC. When the oscillator is FM modulated, the Sub
OSC never gets negatively affected by this modulation; and it can maintain
giving the frequency clearly. You can also switch the oscillator to the LFO
mode. You can create subtractive syntheses by using two or more of these
oscillators or by mixing these waveforms. The main reason for us to design
this oscillator is, as its name shows, to enable the creation of complex FM
patches and sounds by using 2-3 or more of these oscillators, just like
Operator FM. While Thru Zero FM increases the modulation, it can maintain
giving the same frequency without losing the adjusted frequency; and you can
add harmonics to the sound musically. The module has 5 knob controls, 4 CV
Inputs, an input for Waveshaper, and 6 +5V waveform outputs. Osi-OP, which is
hand-made and produced with the help of Through Hole technology, is a product
consisting of electronic components that is carefully tested.
FRONT PANEL
+12v 45mA
-12v 35mA
- Depth 40mm
- from panel to ribbon cable (including ribbon cable size)
1. Knob 1 – Tune – Tune Range 3.5hz – 7khz
2. Knob 2 – Fine Tune
3. Knob 3 – Thru Zero FM Input Attenuator
4. Knob 4 – Exponential FM
5. Knob 5 – Pulse Width Modulation / Waveshape Morphing
6. 1V/OCT CV Input (+8V)
7. Exponential CV Input (+8V)
8. Thru Zero FM Input (+8V) (AC Coupled)
9. PWM /WS Morphing CV Input (+5V)| 10. WS Morphing Wave Input
11. Sine Wave Output (+5V / 10Vpp) (1k ohm)
12. Triangle Wave Output (+5V / 10Vpp) (1k ohm)
13. Sawtooth Wave Output (+5V / 10Vpp) (1k ohm)
14. Square Wave Output (+5V / 10Vpp) (1k ohm)
15. Square Sub OSC Output (10vpp) (1k ohm)
16. Waveshape Output (+5V / 10Vpp) (1k ohm)
17. LFO / OSC Switch
18. Led indicates oscillator’s oscillation
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THE RULES YOU SHOULD SE CAREFUL ABOUT
The module is connected to the eurorack bus board with a flat (ribbon) cable,
and this is how it takes the necessary energy from the power supply. While
connecting the flat (ribbon) cables to the module and the bus board, the red
line under the cable represents the -12V in the power supply, and the cable
must be connected to both sides in the right direction. Otherwise, you may
damage your module and your whole system. The direction of the red cable is
marked as “Red Stripe” on the module. This mark shows the direction of the
cable and the -12V. After the connection, make sure you double-check, and then
you can turn on the power supply.
If you do not make the right connection, the module will be out of warranty.
This mistake may damage your whole system and the other modules.
Make sure that the power supply is turned off while connecting the flat
(ribbon) cable to the bus board. When the power supply is on, do not try to
connect the module to the power supply or the bus board.
It is recommended that you use your module and Eurorack at room temperature
(25 Celcius degrees).
Do not use the module in a humid environment.
Do not connect outputs with other outputs. Any complications caused by this
mistake will terminate the warranty of the product.
Make sure that the tips of the cables, which are connected to the outputs, are
not touching the panels of the modiules.
We recommend you to use the module after 30-45 minutes so that it can heat and
it can be calibrated in the right way. You can realize that there is a tune
drift in the oscillator if you do not wait. To reach the necessary
temperature, there must be a signal flow in all the inputs and outputs.
CALIBRATION
We calibrated this module sensitively. Do not touch the trimpots before
turning the module on. If your working environment does not have a stable
temperature, there may be various problems and complications caused by the
change in the heat. If you travel a lot with the module, there will be a
calibration drift. In this case, you will need to re-calibrate it.
Start calibrating the module after heating it for between 30 and 45 minutes.
When the power cable is connected to the module, be careful not to touch the
circuit board at all while trying to calibrate the module. Do not put the
module on a conductive place or material.
At the back of the module, there are 4 blue trimpots. Let’s talk about these
trimpots. For the right tuning, there is 1V-OCT calibration and its high
frequency (HF Track) trimpot. While calibrating, you can use a tuner. The
other two trimpots are for Sine Wave Output. One of the trimpots is Sine Wave
Gain, and the other is Sine Wave Shape. We do not recommend you to tune up
Sine Wave Gain if you do not have an oscilloscope or you do not know how to
use it. Our company is not responsible for the problems caused by this kind of
mistake, these kinds of problems/mistakes are not covered by the guarantee.
You can tune up Sine Wave Shape with an oscilloscope or a frequency spectrum
analyzer. While tuning up, it is advised that you should listen to the sounds,
as well.
Connect a wave out of the oscillator to a tuner for 1V/OCT calibration. For
example, adjust the tuning knob on the module to a lower octave C(Do) note.
(Example: C1). You will need a sequencer or an analog cv keyboard to calibrate
the 1V/OCT input. CO note on the keyboard or on the sequencer will be Ov.
Press this note and connect the CV cable to the 1V/OCT input of the
oscillator. To check if the keyboard or the sequencer is Ov, try to see that
the oscillator tune is not changing when you connect the cable. Then, press
the C1 note, which is an octave higher, and check the oscillator tune on the
tuner. When you press the C1 note and make it an octave higher, turn the
trimpot counterclockwise if the tune gets high pitched. If the tune gets low
pitched, turn the trimpot clockwise. Do not forget that low frequency also
changes when you stabilize or change the high frequency. Check this procedure
by going back and forth between CO and C1. If you are certain that there is a
1-octave range, you can check the CO-C2 range now. Follow the same procedure
for this range. You can check all the octaves one by one with this method. The
oscillator can work in the right tuning on 3.5 octaves. Do not try to go
further. For the third octave, you can try and adjust the HF Track trimpot.
We, as Vaemi, send you the module after getting HF Track trimpot and 1V/OCT
calibration ready. If you need to re-adjust it later, make sure that the HF
Track trimpot is turned off completely, and then you can adjust 1V/OCT
trimpot. 1V/OCT trimpot, on its own, will not tune up perfectly in 3.5
octaves. Adjust it as sensitively as you can, and then adjust the HF Track
trimpot. If you turn the HF Track trimpot clockwise, it will cause high
octaves to get high pitched.
You can use a frequency spectrum analyzer and an oscilloscope to adjust the
Sine Wave Shape. First, forward the Sine Wave Output of the oscillator to
these devices. You can adjust Sine Wave Shape freely either for a perfect
curve or for a harmonically rich way for your ears. When Sine Wave sounds
right and pure, it will sound much louder when used with your bass patches or
as sub osc. On the contrary, you may choose to use the harmonically rich
version with your Thru Zero FM patches. You can adjust the Sine Wave Gain
trimpot with the help of an oscilloscope. Measure the peak-to-peak voltage
range of the waveform you sent with the help of an oscilloscope, and adjust it
as 10Vpp. When you turn the trimpot clockwise, it will add gain. When you turn
it counterclockwise, the gain will decline.
WARRANTY CONDITIONS
Vaemi gives a one-year warranty for this product. The warranty period starts
after the day you buy the product. (A proof of purchasing / a bill is
required). Mistakes such as using the wrong power supply, connecting the cable
to the bus board or the module in the wrong way, using a faulty flat (ribbon)
cable, taking off the components, changing the front board, forwarding an
output to another one will take the product out of warranty. In such a case,
you will need to pay the normal service fee. Vaemi is not responsible, and
will not take responsibility, for the damage that the product or the user may
face because of operating the product. During the warranty period, a faulty
product will be repaired by Vaemi for free.
Shipping fees for sending the product back to Vaemi will be paid by the buyer.
For your further questions, please contact us on
vaemisynth@gmail.com.
CE/REACH Compliant/RoHS Compliant
All Vaemi product are assembled with parts and materials that are compliant
with CE/REACH/RoHs standards.
made in Turkiye