Synth & Eurorack Parts / DIY

Our Synth & Eurorack Parts / DIY category is a curated list of items that are commonly found in synth/eurorack projects. The items and filters here do not represent our full lineup of parts. If you don't see what you are looking for, check out our main categories or send us a suggestion and we'll look into adding it.
Evaluation Board - EVB2130-P, SSI2130 VCO, Sound Semiconductor, Fully Populated
The SSI2130 offers unprecedented performance and features, but its ultra-compact QFN package can present prototyping challenges. The EVB2130 eases evaluation by providing a PCB that allows comprehensive exploration of capabilities. The EVB2130-P is fully populated and ready for the bench. With the exception of the SSI2130, all components are through-hole for easy construction and experimentation. A on-board +5V regulator and 2.5V reference simplify external power connections, and pots are provided for mixer control, PWM, and VCO setup. Switches ease selection of saw ramp direction plus Through-Zero and Pulse Modulation. Features
  • PCB size: 108 x 82mm
  • External Power: ±12V
  • Inputs: Expo Freq 1V/Oct PWM In Aux 1 and 2 In FM In PM In Hard Sync Soft Sync
  • Outputs: Sine Saw Triangle Pulse Square Mix Out
$110.95
Integrated Circuit - Experimental Noize FXCore, DSP, Multi-Effect / Reverb
FXCore from Experimental Noize is a DSP designed for creating audio effects in pro-audio devices. FXCore can operate as a standalone device when paired with appropriate CODECs where it generates all necessary clocks or as part of a more complex system where it will lock to the word clock and bit clock provided by another part of the system.
FXCore can store up to 16 programs and their associated register preset values in its internal FLASH memory so no external program storage is required.
$19.95
Integrated Circuit - Spin FV-1, DSP, Multi-Effect / Reverb
The Spin Semiconductor FV-1 is a complete reverb solution in a single IC. With integrated stereo ADC and DACs, the FV-1 can be treated like any other analog component in your product's signal path. The FV-1 can access a total of 16 programs, 8 are built into the internal ROM and the designer may elect to connect a serial EEPROM with 8 additional programs. By using an external EEPROM, the designer can distinguish his product from others by creating a custom program set without the need for a microprocessor in the system. With 3 potentiometer inputs, programs may have real time variable parameters such as decay time in a reverb, rate and depth in a chorus or frequency in a filter. These inputs are available as coefficients to your program and may be used independently of each other. The rich instruction set allows users to program effects of all kinds. With instructions like LOG and EXP, users can easily program audio expansion and compression routines.
$17.50
Integrated Circuit - DAB2130, VCO, Sound Semiconductor
The Sound Semiconductor DAB2130 is a pre-soldered DIP converter for the SSI2130. This board features the SSI2130 and two decoupling caps for the V+ and V- inputs. The pinout is labelled on the board and matches the QFN pinout. This adapter features a 32 pin DIP base with a .600 in. width. The pins are standard male headers so 2.54mm female headers are recommended for socketing the board. For the standard QFN version, please see P-Q-SSI2130. The first new VCO IC in decades, and worth the wait! The FatKeys™ SSI2130 Voltage Controlled Oscillator provides beautiful triangle, sawtooth, pulse, and square waveforms with unprecedented temperature stability; and adds an on-chip mixer, low distortion sine wave generator, through-zero FM/PM capability and more in an ultra-compact PCB footprint. The SSI2130 is a new-generation voltage controlled oscillator subsystem for high-performance electronic musical instruments.
$16.95
Integrated Circuit - DAB2140, Multi-Mode VCF, Sound Semiconductor
The Sound Semiconductor DAB2140 is a pre-soldered DIP converter for the SSI2140. This board features the SSI2140 and two decoupling caps for the V+ and V- inputs. The pinout is labelled on the board and matches the SSOP pinout. This adapter features a 20 pin DIP base with a .600 in. width. The pins are standard male headers so 2.54mm female headers are recommended for socketing the board. For the SSOP version, please see P-Q-SSI2140. A refresh of a classic design, the FatKeys™ SSI2140 preserves mojo of the beloved SSM2040 and adds temperature compensation of gm cells and the exponential control port. A "Q VCA" is provided to allow easy resonance control as well as various options for Q compensation.
$16.95
Op-Amp - LM358H, Dual, 8-Pin TO-99 package
LM358H dual op amp in an 8-pin TO-99 package. The LM358H series consists of two independent, high gain, internally frequency compensated operational amplifiers which were designed specifically to operate from a single power supply over a wide range of voltages. Operation from split power supplies is also possible and the low power supply current drain is independent of the magnitude of the power supply voltage. Application areas include transducer amplifiers, dc gain blocks and all the conventional op-amp circuits which now can be more easily implemented in single power supply systems.
$10.95
Integrated Circuit - AS3372E, Synth Voice, Alfa, 24 Pin DIP
The AS3372E is Alfa’s take on the CEM3372 µP Controllable Signal Processor in a DIP-24 package. The AS3372E features an additional two VCA’s so an adapter board is required when using as a replacement for the CEM version. The CEM version was used in multiple classic synths, including the Oberheim Matrix 12, Oberheim Xpander, Sequential Prophet T8, Sequential Prophet 600, Akai AX80, Rhodes Chroma Polaris, and more.
$10.95
Integrated Circuit - AS3340A, VCO, Alfa, 16-Pin Dip
The AS3340A is Alfa’s version of the CEM3340 IC. The AS3340A is a completely self-contained, precision voltage controlled oscillator, featuring both exponential and linear control scales and up to four buffered output waveforms: triangle, sawtooth, square, and pulse with voltage controllable pulse width. Full temperature compensation makes these VCOs extremely stable, and eliminates the need for a temperature compensation resistor. The highly accurate exponential and linear control inputs are virtual ground summing nodes, allowing multiple control voltages to be mixed within the device itself.
Also included is provision for hard and soft synchronization of the frequency, and an output for easy adjustment of high frequency tracking. Special care in the design ensures oscillation start-up under any power-on sequence and supply conditions.
An on-chip 7.4 volt Zener diode allows the device to operate off ±15 volt supplies, as well as +12, -5 volt supplies.
$7.95
OTA - AS3280, Dual, Linearizing Diodes, Alfa, 16-Pin DIP
The AS3280 is Alfa’s version of the CA3280 IC. The AS3280 consists of two variable operational amplifiers that are designed to substantially reduce the initial input offset voltage and the offset voltage variation with respect to changes in programming current. This design results in reduced "AGC thump," an objectionable characteristic of many AGC systems. Careful design of critical places of the circuit reduces the amplifier dependence upon thermal and processing variables.
The AS3280 has all the generic characteristics of an operational voltage amplifier except that the forward transfer characteristics is best described by transconductance rather than voltage gain, and the output is current, not voltage. The magnitude of the output current is equal to the product of transconductance and the input voltage.
$7.95
Op-Amp - AS301AH, Alfa, Single, TO5-8 case
The AS301AH is Alfa’s version of the LM301A in an 8 pin TO5 package. The AS301A is a general purpose operational amplifier. This amplifier offers many features which make its application nearly foolproof: overload protection on the input and output, no latch-up when the common mode range is exceeded, and freedom from oscillations and compensation with a single 30 pF capacitor. It has advantages over internally compensated amplifiers in that the frequency compensation can be tailored to the particular application. For example, in low frequency circuits it can be overcompensated for increased stability margin. Or the compensation can be optimized to give more than a factor of ten improvements in high frequency performance for most applications. In addition, the device provides better accuracy and lower noise in high impedance circuitry.
$7.95
Integrated Circuit - AS3360, Dual VCA, Alfa, 14-Pin Dip
The AS3360 is Alfa’s version of the CEM3360 IC. The AS3360 is a dual general purpose voltage controlled transconductor intended for such applications as voltage controlled amplifiers, filters, and waveform generators. Each transconductor independently provides both linear and exponential control scaling over greater than a 100 dB range. Complete with virtual ground summing inputs, wide voltage compliance current outputs, and control inputs referenced to ground, the AS3360 requires exceptionally few external components and is extremely easy to use. Because of its inherent ultra-low control feedthrough, no trimming is required.
$7.95
On Backorder
Integrated Circuit - AS3109D, VCF, Alfa, SOIC-16
The AS3109 is Alfa’s version of the Roland IR3109 VCF in an SOIC package. The AS3109 is a high performance voltage controlled four-pole filter. The four independent sections may be interconnected to provide a wide variety of filter responses, such as low pass, high pass, band pass and all pass. A single input exponentially controls the frequency over a range greater than 15 octaves with little control voltage feedthrough. AS3109 features high input impedance buffers. Features
  • Voltage controllable range – 15 octaves
  • Accurate exponential frequency scale
  • High input impedance buffers
  • Wide transconductance range
  • Low input offset voltage
  • Low control voltage feedthrough - 45 dB typical

Applications
  • For electronic music
$7.95
OTA - AS3080E, Linearizing Diodes, Alfa, 8-Pin DIP
The AS3080E is Alfa’s version of the CA3080 IC. The AS3080E is a gain block which is the operational-transconductance-amplifier (OTA). The AS3080E has differential input and a single-ended, push-pull, class A output. Amplifier bias
input may be used either for gating or for linear gain control. High output impedance and transconductance (gM) is directly proportional to the amplifier bias current (IABC). Linearizing diodes are provided at the inputs to reduce distortion and allow higher input levels. The result is a 10-dB signal-to-noise improvement referenced to 0.5 percent THD.
The AS3080E is notable for it’s high slew rate (50V/µs), which makes it especially useful for multiplexer and fast unity-gain voltage followers.
$6.50
Integrated Circuit - SSI2130, VCO, Sound Semiconductor
The FatKeys™ SSI2130 Voltage Controlled Oscillator provides beautiful triangle, sawtooth, pulse, and square waveforms with unprecedented temperature stability; and adds an on-chip mixer, low distortion sine wave generator, through-zero FM/PM capability and more in an ultra-compact PCB footprint.
$5.95
On Backorder
Integrated Circuit - AS571D, Compandor, Alfa, SOIC-16
The AS571D is Alfa’s version of the NE571 or SA571 in an SOIC package. AS571 is a versatile low cost dual gain control circuit in which either channel may be used as a dynamic range compressor or expandor. Each channel has a full-wave rectifier to detect the average value of the signal, a linearized temperature-compensated variable gain cell, and an operational amplifier. AS571 is well suited for use in VCA blocks, noise reduction systems, compandors/expanders ,etc. Features
  • Complete compressor and expandor
  • Temperature compensated
  • Channel separation >86 dB
  • Greater than 110 dB dynamic range
  • Levels adjustable with external components
  • Distortion may be trimmed out

Applications
  • VCA
  • High level limiter
  • Low level expandor − noise gate
  • Dynamic filters
  • Dynamic noise reduction systems
$5.95
Integrated Circuit - AS3320, Multi-Mode VCF, Alfa, 18-Pin Dip
The AS3320 is Alfa’s version of the CEM3320 IC. The AS3320 is a high performance voltage controlled four-pole filter with on-chip voltage controllable resonance IC. The four independent sections may be interconnected to provide a wide variety of filter responses, such as low pass, high pass, band pass and all pass. A single input exponentially controls the frequency over greater than a ten octave range with little control voltage feedthrough. Another input controls the resonance in a modified linear manner from zero to low distortion oscillation. For those demanding applications, provision has been made to allow trimming for improved control voltage rejection. Each filter section features a variable gain cell which is fully temperature compensated, exhibits a better signal-to-noise ratio and generates its low distortion predominantly in the second harmonic. The device includes a minus two volt regulator to ensure low power dissipation and consequent low warm-up drift.
$5.95
Integrated Circuit - AS3310, VC ADSR, Alfa, 16-Pin Dip
The AS3310 is Alfa’s version of the CEM3310 IC. The AS3310 is a self-contained, precision ADSR type of envelope generator intended for electronic music and other sound generation applications. Attack, decay and release times are exponentially voltage controllable over a wide range, and the sustain level is linearly voltage controllable from 0 to 100% of the peak voltage Vp. All four control Inputs are Isolated from the rest of the circuitry so that the control pins of tracking units may be simply tied together.
On the negative power output, there is an internal Zener diode at 7.4 volts ± 10%, which allows the chip to supply a maximum voltage of ± 15 volts with a current-limiting resistor REE, and a minimum positive supply voltage of + 11 volts and a minimum negative supply voltage of -5 volts.. A series current limiting resistor must be added between pin 6 and the supply.
$5.85
Transistor - AS395H, Matched Pair, Alfa, TO5-8 case, PNP
The AS395 dual monolithic PNP transistor offers excellent parametric matching and high frequency performance. Low noise characteristics (1 nV/√Hz typ @ 1 kHz), high bandwidth (190 MHz typical), and low offset voltage (100 µV max), makes the AS395 an excellent choice for demanding preamplifier applications.Tight current gain matching (3% max mismatch) and high current gain (100 min), over a wide range of collector current, makes the AS395 an excellent choice for current mirrors. A low value of bulk resistance makes the AS395 an ideal component for applications requiring accurate logarithmic conformance. To ensure the long-term stability of the matching parameters, internal protection diodes across the base-emitter junction clamp any reverse base-emitter junction potential.
$5.50
Op-Amp - OPA2134, Dual, High Performance Audio, 8-Pin DIP
OPA2134 SoundPlus™ Audio dual op-amp with low distortion, low noise and precision. The OPA2134 are ultra-low distortion, low-noise operational amplifiers fully specified for audio applications. A true FET input stage is incorporated to provide superior sound quality and speed for exceptional audio performance. This, in combination with high output drive capability and excellent DC performance, allows for use in a wide variety of demanding applications. In addition, the OPA2134 has a wide output swing, to within 1 V of the rails, allowing increased headroom and making it ideal for use in any audio circuit. The OPA2134 SoundPlus™ audio operational amplifiers are easy to use and free from phase-inversion and the overload problems often found in common FET-input operational amplifiers. They can be operated from ±2.5-V to ±18-V power supplies.
$5.40
Integrated Circuit - SSI2131, VCO, Sound Semiconductor
The FatKeys™ SSI2131 Voltage Controlled Oscillator provides the core VCO function with buffered triangle, sawtooth, and variable-width pulse waveform outputs over a ten-octave range. The device offers unparalleled temperature stability, exponentiality, waveform integrity, and ease of use while requiring an absolute minimum of external components. The SSI2131 is a new-generation voltage controlled oscillator for high-performance electronic musical instruments and other systems requiring accurate audio-band waveform generation. The device offers unprecedented levels of temperature stability, exponentiality, waveform integrity, and ease of use.
$5.25
Integrated Circuit - SSI2140, Multi-Mode VCF, Sound Semiconductor
The SSI2140 is a new-generation voltage controlled filter that provides four highly-configurable variable transconductance cells for a wide variety of pole and mode combinations, and adds significant new features.
$5.25
Transistor - AS394CH, Matched Pair, Alfa, TO5-8 case, NPN
The AS394CH is a junction isolated ultra well-matched monolithic NPN transistor pair with an order of magnitude improvement in matching over conventional transistor pairs. Electrical characteristics of these devices such as drift versus initial offset voltage, noise, and the exponential relationship of base-emitter voltage to collector current closely approach those of a theoretical transistor. Extrinsic base and emitter resistances are very low, giving very low noise and operating over a wide current range. To guarantee long term stability of matching parameters, internal clamp diodes have been added across the emitter-base junction of each transistor. These prevent degradation due to reverse biased emitter current, the most common cause of field failures in matched devices.
$4.95
Integrated Circuit - SSI2144, Ladder VCF, Sound Semiconductor
The second of two legendary SSM filter updates, the FatKeys™ SSI2144 is a dedicated four-pole low-pass ladder filter with on-chip resonance control. Original designer Dave Rossum did a number of performance updates such as lower noise, improved control feedthrough, and logical pin grouping but otherwise left this sweet-sounding VCF alone. The SSI2144 reprises the SSM2044 of legacy chipmaker Solid State Micro Technology, which many believe to be the best-sounding analog synthesis filter IC ever produced. Based on Dave Rossum’s patented classic improved ladder topology, the SSI2144 allows rich tonal characteristics that showcase the very best attributes of subtractive synthesis. The SSI2144 uses the same internal circuit as the SSM2044 but incorporates improvements by the original designer and takes advantage of modern process technology.
$4.95
Integrated Circuit - SSI2164, Quad VCA, Sound Semiconductor
The FatKeys™ SSI2164 is perhaps the most flexible VCA available, with four independent channels for lowest cost-per-VCA. The user-selectable mode control allows Class A, AB, or intermediate biasing, and current inputs and outputs provide great design freedom. Ideal for voltage-controlled filters. The SSI2164 is a versatile VCA building block for high-performance audio applications. Four independent channels provide voltage control of current-mode inputs and outputs for a gain range from +20dB to –100dB, with control provided by a ground-referenced –33mV/dB constant. The SSI2164 will directly retrofit existing SSM/V2164 positions while offering improvements that include significantly lower overall distortion, on-chip protection against asymmetrical power failure, and a substantial increase of input current handling. The device offers considerable flexibility for a wide range of design goals and applications.
$4.95