
MiniDJ Back
Thorinair/Avalon-Harmonics
A collection of Avalon Harmonics branded synthesizer modules.

In this oscillator, increasing the Bounce raises the frequency. Narrowing the Bounds further increases the frequency but reduces the amplitude.
BBO&VCA v1.0 is an open-source printed circuit board by StudioKAT, from the StudioKAT/BBO-VCA repository on GitHub. It is a 2-layer board of 90.2 × 128.5 mm with 124 parts on 91 nets, routed with 597 tracks and 156 vias.
It is built around the LM13700M, BCM857BS and 1N4148WS, with the 1N5819WS and MMBT3906 among its other parts. Its parts include 54 resistors, 19 capacitors, 9 connectors, 6 diodes and 6 transistors.

BBO&VCA は、Ieaskul F. Mobenthey の Denum と crucFX Utility BBO にインスパイアされた「バウンズ・バウンス・オシレーター(Bounds Bounce Oscillator)」です。
この回路は、「バウンス(Bounce)」と「バウンズ(Bounds)」という、2つの概念を軸に動作します。
ボールが2つの壁の間を行き来して跳ねている様子をイメージしてください。バウンスはボールのスピード、バウンズはその2つの壁の距離です。
このオシレーターでは、バウンスを大きくすると周波数が上がり、バウンズを狭めると振幅が下がる代わりに周波数はさらに上がります。つまり、壁を近づけると、ボール(信号)の移動が速くなるという構造です。
BBO&VCA は、バウンスとバウンズをそれぞれ独立して調整・変調でき、主出力からは常に三角波が出力されます。また、もう1つの出力からは矩形波が得られます。
さらに、レンジスイッチにより3つの動作範囲を選択できます:
出力される三角波と矩形波は、それぞれ専用のリニアVCAを通して出力されており、外部CVやノブで音量(振幅)をコントロールできます。
※ 1V/oct の標準CVピッチ制御には対応していません。
BBO&VCA is a "Bounds Bounce Oscillator" inspired by Ieaskul F. Mobenthey's Denum and the crucFX Utility BBO.
This circuit operates based on two key concepts: Bounce and Bounds.
Imagine a ball bouncing back and forth between two walls. The Bounce represents the speed of the ball, and the Bounds represent the distance between the two walls.
In this oscillator, increasing the Bounce raises the frequency. Narrowing the Bounds further increases the frequency but reduces the amplitude.
In other words, when the walls are brought closer together, the ball (i.e., the signal) travels faster, resulting in a higher pitch.
BBO&VCA allows independent control and modulation of both Bounce and Bounds.
The main output always produces a triangle wave, while the secondary output provides a square wave.
A range switch allows you to select from three operating ranges:
Both the triangle and square waves are routed through dedicated linear VCAs, allowing you to control their amplitude (volume) via knobs or external CV.
Note: This module does not support standard 1V/oct pitch tracking.
StudioKATオフィシャルショップで販売しています。(日本国内限定)
https://www.studiokat.jp/items/113562094
この作品は Creative Commons 表示 - 継承 4.0 国際 (CC BY-SA 4.0) の下でライセンスされています。
This work is licensed under the Creative Commons Attribution-ShareAlike 4.0 International License.
2025-07-17 Released version 1.0| Qty | Value | Footprint | References |
|---|---|---|---|
| 10 | 100nF | Capacitor_SMD:C_0603_1608Metric | C3, C4, C5, C6, C7, C8, C9, C10, C11, C12 |
| 9 | 10K | Resistor_SMD:R_0402_1005Metric | R11, R12, R20, R22, R26, R29, R30, R49, R50 |
| 8 | PH_Audio | kat_eurorack:PH_AudioJack_3.5mm_Pad | H11, H12, H13, H14, H15, H16, H17, H18 |
| 6 | 100K | Resistor_SMD:R_0402_1005Metric | R6, R8, R9, R10, R19, R21 |
| 6 | 4.7K | Resistor_SMD:R_0402_1005Metric | R13, R14, R15, R16, R51, R53 |
| 4 | 10M | Resistor_SMD:R_0402_1005Metric | R1, R2, R3, R4 |
| 4 | 1K | Resistor_SMD:R_0402_1005Metric | R39, R40, R52, R54 |
| 4 | 22K | Resistor_SMD:R_0402_1005Metric | R5, R7, R27, R28 |
| 4 | 47K | Resistor_SMD:R_0402_1005Metric | R17, R18, R24, R25 |
| 4 | 680R | Resistor_SMD:R_0402_1005Metric | R43, R44, R45, R46 |
| 4 | B50K | kat_eurorack:Potentiometer_RV09 | RV1, RV2, RV3, RV4 |
| 4 | BCM857BS | Package_TO_SOT_SMD:SOT-363_SC-70-6 | Q1, Q2, Q3, Q4 |
| 4 | PH_Pot | kat_eurorack:PH_RK097_15mmKnob_Pad | H5, H6, H9, H10 |
| 3 | TL074 | Package_SO:SOIC-14_3.9x8.7mm_P1.27mm | U3, U4, U5 |
| 2 | 15K | Resistor_SMD:R_0603_1608Metric | R31, R32 |
| 2 | 18K | Resistor_SMD:R_0402_1005Metric | R47, R48 |
| 2 | 1N4148WS | Diode_SMD:D_SOD-323 | D3, D4 |
| 2 | 1N5819WS | Diode_SMD:D_SOD-323 | D1, D2 |
| 2 | 22uF | Capacitor_SMD:C_0805_2012Metric | C1, C2 |
| 2 | 330K | Resistor_SMD:R_0402_1005Metric | R33, R34 |
| 2 | 330pF | Capacitor_SMD:C_0402_1005Metric | C16, C17 |
| 2 | 33K | Resistor_SMD:R_0402_1005Metric | R35, R36 |
| 2 | 47pF | Capacitor_SMD:C_0402_1005Metric | C18, C19 |
| 2 | 6.8K | Resistor_SMD:R_0402_1005Metric | R37, R38 |
| 2 | B100K | kat_eurorack:Potentiometer_RV09 | RV5, RV6 |
| 2 | LED_Dual_Bidirectional | LED_THT:LED_D3.0mm | D5, D6 |
| 2 | LM13700 | Package_SO:SOIC-16_3.9x9.9mm_P1.27mm | U1, U2 |
| 2 | MMBT3906 | Package_TO_SOT_SMD:SOT-23 | Q5, Q6 |
| 2 | PH_LED | kat_eurorack:PH_LED_3.0mm_Pad | H3, H4 |
| 2 | PH_Pot | kat_eurorack:PH_RK097_15mmKnob_Uni_Pad | H7, H8 |
| 1 | 1nF | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C13 |
| 1 | 1uF | Capacitor_SMD:C_1206_3216Metric_Pad1.33x1.80mm_HandSolder | C14 |
| 1 | 240K | Resistor_SMD:R_0603_1608Metric | R41 |
| 1 | 360K | Resistor_SMD:R_0603_1608Metric | R42 |
| 1 | 470K | Resistor_SMD:R_0402_1005Metric | R23 |
| 1 | 47nF | kat_eurorack:C_1913_4833Metric | C15 |
| 1 | Bounce_CV | kat_eurorack:AudioJack_PJ301M-12 | J3 |
| 1 | Bounce_Lin | kat_eurorack:AudioJack_PJ301M-12 | J2 |
| 1 | Bounds_CV | kat_eurorack:AudioJack_PJ301M-12 | J5 |
| 1 | Bounds_Lin | kat_eurorack:AudioJack_PJ301M-12 | J4 |
| 1 | PH_SW | kat_eurorack:PH_ToggleSwitch_5.1mm_Pad | H2 |
| 1 | POWER | kat_eurorack:BoxHeader_2x05_2.54mm_Europower_2 | J1 |
| 1 | Panel | kat_eurorack:Panel_8HP | H1 |
| 1 | SW_SPDT_MSM | kat_eurorack:ToggleSwitch_2MS1-T2-B4-M2-Q-E-S | SW1 |
| 1 | Square_OUT | kat_eurorack:AudioJack_PJ301M-12 | J9 |
| 1 | Triangle_OUT | kat_eurorack:AudioJack_PJ301M-12 | J8 |
| 1 | VCA_CV_Square | kat_eurorack:AudioJack_PJ301M-12 | J7 |
| 1 | VCA_CV_Triangle | kat_eurorack:AudioJack_PJ301M-12 | J6 |
It measures 90.2 × 128.5 mm and has 2 copper layers, 1.6 mm thick.
124 parts, built around the LM13700M, BCM857BS, 1N4148WS and 1N5819WS. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
From the StudioKAT/BBO-VCA repository on GitHub, at the commit this page was made from: the board is v1.0/KiCAD/BBO&VCA_v1.0/BBO&VCA_v1.0.kicad_pcb and its schematic v1.0/KiCAD/BBO&VCA_v1.0/BBO&VCA_v1.0.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Its repository states no licence, so its author keeps all rights: ask StudioKAT before reusing the design.

Thorinair/Avalon-Harmonics
A collection of Avalon Harmonics branded synthesizer modules.



mzuelch/CATs-Eurosynth
Analog Synth Eurorack Modules


Emute-Lab-Instruments/Myriad
Sources for Emute Lab Instruments Myriad eurorack module


fpga-theremin/sensors
Implementation of Analog Front End for digital theremin sensor