IGS Audio Tubecore 3U – Vari-Mu Mastering Compressor
The finest Mastering Compressor to garnish your Masters!
The IGS Audio Tubecore 3U has become an IGS studio hardware classic since its 2017 launch. In a crowded tube compressor market, it has earned standard status in recording, mixing, and mastering studios worldwide.
Details
Housed in a sleek black chassis reminiscent of the legendary Fairchild 670, the Tubecore 3U stands as an independent design – no mere clone.
Variable Gain-Staging
The thoughtful gain-staging unfolds in 3–4 steps per channel:
Input gain: 1–24 dB
Compression amount: 0 to -12 dB
Output gain: 1–24 dB
Wet/dry blend for precise parallel compression control
Side-Chain Function
Built-in sidechain (60–120 Hz) prevents bass from overdriving the compressor, avoiding squashed/pumped effects. Six attack (0.1–30 ms) and release (0.1–4 s) times deliver punchy, warm results – from subtle to aggressive density.
Dual-Mono or M/S Mode
Two clever bypass switches allow instant mode switching without knob adjustments.
Clever feature: Dual bypass modes for dual-mono and M/S compression (image caption)
Two classic 1950s-style VU meters on the front panel lend a noble look, complemented by two bypass switches and a ruby-red power LED. The external power supply ensures even, clean, interference-free operation. Uniquely, direct rear access to the tubes prioritizes user sound taste and flexibility.
Your turn: Pick your favorite tube! Two rear slots await!
User-Customizable Tubes
Fixed Russian 6N1P-WE double-triodes pair with two user-selectable sockets for Fairchild 6386, 6BC8 (Universal Audio 176 style), or 5670 tubes – blending tight transparency to dark-warm coloration.
Premium components: Carnhill input/output transformers, NOS tubes, 1% metal-film resistors, Wima capacitors, relay-based sidechain low-cut.
In summary, the Tubecore 3U offers exceptional value: intuitive, high-build quality, versatile for mastering, drums, bass/vocals, parallel buses, and mixbus processing. Upgrade your chain – order now at Falkenstein ProAudio.
Discover the complete IGS Audio portfolio: IGS Audio Studio Equipment – One LA 500, V8 Bus Compressor & more.
IGS Audio Tubecore 3U - Vari Mu Tube Mastering Compressor
- Variable-Mu compressor
- Dual-Mono / Mid-Side
- Internal Sidechain-Filter
- IGS Custom Made Audio Transformers
- 24-stage Elma switches
- Attack: 0.1 – 30 ms
- Release: 0.1 – 4 s
- Frequency range: 20Hz to 20kHz +/- 0.2dB
- Operating level: +4dBu
- Max. Input level: +22 dBu
- Max. Output level: +22 dBu
- Dynamic range: >107 dBA (@ 1kHz, +24 dBu)
- Max. Gain: +35dB
- Max. Gain reduction: 20 dB
- SNR: 87 dBA
- THD: 0.12 %
- THD+N: 0.15 %
- IMD (SMPTE): 0.32%
- Crosstalk: 82 dB



Reviews
The IGS Audio Tubecore 3U is a modern classic and no simple knockoff from a retro unit.
This unit alone is worth going out in the analog domain.I use it daily and it really makes my masterings and stems shine!
Der IGS Tubecore 3U veredelt mir regelmäßig Mixe/Master.
Essentielles Analogtool, man möchte ihn nicht mehr her geben!