125B · 4 knobs
Aurora DeluxeCompressor
Based on the Keeley Compressor Plus
- Category
- Compressor
- Controls
- Sustain · Blend · Tone · Level
- Difficulty
- Intermediate
- Price
- $12.50in stock
From the vendor
An expanded version of the classic Keeley Compressor with an added clean blend, treble control, and output buffer.
The Aurora Deluxe Compressor is based on the Keeley Compressor Plus, an updated version of their world-famous compressor. It was first released in 2017 and was traced by Aion FX in 2023.
Internally, it’s a Ross/Dyna Comp as with the original compressor circuit. A clean blend has been added, as well as a subtle treble control that boosts very high frequencies and adds a touch of brightness or presence. To make room for the two new knobs, they omitted the Clipping knob (an input attenuator) as well as converting the Attack knob to a two-position switch. It’s also been converted to use the LM13700, a current-production version of the obsolete CA3080.
The Compressor Plus fully replaced the previous Compressor. In fact, the standard version artwork omits the “Plus” and just labels it the “Keeley Compressor” in the same font as the original, though the product description does call it the Compressor Plus.
The Aurora Deluxe is a direct adaptation based on our trace of the Compressor Plus. The only difference is that we added a third position to the Attack (Release) switch that simulates the 12:00 position on the original control. We also combined two series capacitors that were clearly left over from the prototyping process.
Note: This project uses a type of capacitor that has been temporarily discontinued by WIMA. Please see our news article about the issue and the substitution spreadsheet for project-specific recommendations. We are stocking an equivalent from Kemet in the mean time. The build document has not yet been updated to reflect this.
Schematic
The schematic is in the vendor's build document, page 7. Open the build document. No KiCad fragment has been drawn for this circuit yet.
Parts list 92 rows
Report a wrong parse| Ref | Value | Normalized | Type | Notes |
|---|---|---|---|---|
| Resistors 46 | ||||
| R1 | 10k | 10k | Metal film resistor, 1/4W | |
| R2 | 470k | 470k | Metal film resistor, 1/4W | |
| R3 | 470k | 470k | Metal film resistor, 1/4W | |
| R4 | 10k | 10k | Metal film resistor, 1/4W | |
| R5 | 10k | 10k | Metal film resistor, 1/4W | |
| R6 | 1M | 1M | Metal film resistor, 1/4W | |
| R7 | 1k | 1k | Metal film resistor, 1/4W | |
| R8 | 1k | 1k | Metal film resistor, 1/4W | |
| R9 | 220k | 220k | Metal film resistor, 1/4W | |
| R10 | 220k | 220k | Metal film resistor, 1/4W | |
| R11 | 1M | 1M | Metal film resistor, 1/4W | |
| R12 | 15k | 15k | Metal film resistor, 1/4W | |
| R13 | 150k | 150k | Metal film resistor, 1/4W | |
| R14 | 27k | 27k | Metal film resistor, 1/4W | |
| R15 | 10k | 10k | Metal film resistor, 1/4W | |
| R16 | 10k | 10k | Metal film resistor, 1/4W | |
| R17 | 1M | 1M | Metal film resistor, 1/4W | |
| R18 | 39k | 39k | Metal film resistor, 1/4W | |
| R19 | 150k | 150k | Metal film resistor, 1/4W | |
| R20 | 10k | 10k | Metal film resistor, 1/4W | |
| R21 | 1M | 1M | Metal film resistor, 1/4W | |
| R22 | 10k | 10k | Metal film resistor, 1/4W | |
| R23 | 47k | 47k | Metal film resistor, 1/4W | |
| R24 | 10k | 10k | Metal film resistor, 1/4W | |
| R25 | 47k | 47k | Metal film resistor, 1/4W | |
| R26 | 12k | 12k | Metal film resistor, 1/4W | |
| R27 | 15k | 15k | Metal film resistor, 1/4W | |
| R28 | 15k | 15k | Metal film resistor, 1/4W | |
| R29 | 15k | 15k | Metal film resistor, 1/4W | |
| R30 | 15k | 15k | Metal film resistor, 1/4W | |
| R31 | 10k | 10k | Metal film resistor, 1/4W | |
| R32 | 1M | 1M | Metal film resistor, 1/4W | |
| R33 | 1M | 1M | Metal film resistor, 1/4W | |
| R34 | 27k | 27k | Metal film resistor, 1/4W | |
| R35 | 10k | 10k | Metal film resistor, 1/4W | |
| R36 | 100k | 100k | Metal film resistor, 1/4W | |
| R37 | 10k | 10k | Metal film resistor, 1/4W | |
| R38 | 10k | 10k | Metal film resistor, 1/4W | |
| R39 | 390R | 390 | Metal film resistor, 1/4W | |
| R40 | 56k | 56k | Metal film resistor, 1/4W | |
| R41 | 27k | 27k | Metal film resistor, 1/4W | |
| R42 | 10k | 10k | Metal film resistor, 1/4W | |
| R43 | 10k | 10k | Metal film resistor, 1/4W | |
| R44 | 47R | 47 | Metal film resistor, 1/4W | Power supply filter resistor. |
| RPD | 1M | 1M | Metal film resistor, 1/4W | Input pulldown resistor. |
| LEDR | 10k | 10k | Metal film resistor, 1/4W | LED current-limiting resistor. Adjust value to change LED brightness. |
| Capacitors 21 | ||||
| C1 | 150pF | 150p | MLCC capacitor, NP0/C0G | |
| C2 | 22n | 22n | Film capacitor, 7.2 x 2.5mm | |
| C3 | 1uF | 1u | Electrolytic capacitor, 4mm | |
| C4 | 1uF | 1u | Electrolytic capacitor, 4mm | |
| C5 | 1uF | 1u | Film capacitor, 7.2 x 3.5mm | |
| C6 | 1uF | 1u | Electrolytic capacitor, 4mm | |
| C7 | 10n | 10n | Film capacitor, 7.2 x 2.5mm | |
| C8 | 1uF | 1u | Electrolytic capacitor, 4mm | |
| C9 | 1n | 1n | Film capacitor, 7.2 x 2.5mm | |
| C10 | 10n | 10n | Film capacitor, 7.2 x 2.5mm | |
| C11 | 10uF | 10u | Electrolytic capacitor, 5mm | |
| C12 | 10n | 10n | Film capacitor, 7.2 x 2.5mm | |
| C13 | 47n | 47n | Film capacitor, 7.2 x 2.5mm | |
| C14 | 6n8 | 6.8n | Film capacitor, 7.2 x 2.5mm | |
| C15 | 47pF | 47p | MLCC capacitor, NP0/C0G | |
| C16 | 22n | 22n | Film capacitor, 7.2 x 2.5mm | |
| C17 | 47n | 47n | Film capacitor, 7.2 x 2.5mm | |
| C18 | 220uF | 220u | Electrolytic capacitor, 6.3mm | Power supply filter capacitor. |
| C19 | 47uF | 47u | Electrolytic capacitor, 5mm | Reference voltage filter capacitor. |
| C20 | 47uF | 47u | Electrolytic capacitor, 5mm | Reference voltage filter capacitor. |
| C21 | 100n | 100n | MLCC capacitor, X7R | Power supply filter capacitor. |
| Diodes 3 | ||||
| D1 | 1N5817 | 1N5817 | Schottky diode, DO-41 | |
| D2 | 1N914 | 1N914 | Fast-switching diode, DO-35 | |
| D3 | 1N914 | 1N914 | Fast-switching diode, DO-35 | |
| Transistors 5 | ||||
| Q1 | 2N5088 | 2N5088 | BJT transistor, NPN, TO-92 | |
| Q2 | 2N5088 | 2N5088 | BJT transistor, NPN, TO-92 | Original uses MMBT6429 (SMD). 2N5088 is a close |
| Q3 | 2N5088 | 2N5088 | BJT transistor, NPN, TO-92 | substitute. Can also use BC549C, but these will need to be rotated 180 degrees from the silkscreen. |
| Q4 | 2N5088 | 2N5088 | BJT transistor, NPN, TO-92 | |
| Q5 | 2N5088 | 2N5088 | BJT transistor, NPN, TO-92 | |
| ICs 3 | ||||
| IC1 | LM13700N | LM13700N | Transconductance amplifier, dual, DIP16 | Can also use NE5517N. |
| IC2 | RC4558P | RC4558P | Operational amplifier, dual, DIP8 | |
| IC3 | RC4558P | RC4558P | Operational amplifier, dual, DIP8 | |
| Potentiometers 4 | ||||
| SUSTAIN | 500KC | C500k | 16mm right-angle PCB mount pot | Reverse audio (reverse log or antilog) taper. |
| TONE | 100kB | B100k | 16mm right-angle PCB mount pot | Linear taper. |
| BLEND | 10kB | B10k | 16mm right-angle PCB mount pot | Linear taper. |
| LEVEL | 100kA | A100k | 16mm right-angle PCB mount pot | Audio (log) taper. |
| Switches 2 | ||||
| ATTACK | SPDT on-off-on | SPDT ON-OFF-ON | Toggle switch, SPDT center off | |
| FSW | 3PDT | 3PDT | Stomp switch, 3PDT | Available from Aion FX. |
| LEDs 1 | ||||
| LED | 5mm | 5MM | LED, 5mm, red diffused | |
| Jacks & sockets 6 | ||||
| IC1-S | DIP-16 socket | DIP-16 SOCKET | IC socket, DIP-16 | Can also use two DIP-8 sockets. |
| IC2-S | DIP-8 socket | DIP-8 SOCKET | IC socket, DIP-8 | |
| IC3-S | DIP-8 socket | DIP-8 SOCKET | IC socket, DIP-8 | |
| IN | 1/4" mono | 1/4" MONO | 1/4" phone jack, closed frame | Switchcraft 111X or equivalent. |
| OUT | 1/4" mono | 1/4" MONO | 1/4" phone jack, closed frame | Switchcraft 111X or equivalent. |
| DC | 2.1mm | 2.1MM | DC jack, 2.1mm panel mount | Lumberg NEB/J 21 C or equivalent. |
| Hardware 1 | ||||
| ENC | 125B | 125B | Enclosure, die-cast aluminum | Can also use a Hammond 1590N1. |