The IGS Audio Tubecore 3U is a balanced stereo mastering compressor with a fully symmetrical transformer. The design is based on the classic vari-mu solution. In addition to the classic INPUT, THRESHOLD, and OUTPUT controls, it features a switchable sidechain high-pass filter, parallel compression (MIX), independent ATTACK and RELEASE switches, and user-replaceable tubes accessible from the rear of the unit.

The compressor allows you to work in both dual mono and mid/side (M/S) modes. The mode switch has two bypass positions—both do the same thing, but we added the second for convenience and quick A/B comparison.

The Tubecore 3U design is based on the ability to replace the tubes. As a user, you can choose from several types: 6N1P-EW (6N3P-EW) - standard tube set, IGS "standard" compression, 6BC8 / 6BZ8 - tight, transparent, and punchy compression, 6386 - legendary compression by the famous Twin Triode, 5670 - deep and dark tube compression. The User Manual describes in detail how to replace the tubes, making it quick and easy.

The Tubecore 3U design is based on the ability to replace the tubes. As a user, you can choose from several types: 6N1P-EW (6N3P-EW), 6BC8 / 6BZ8, 6386, and 5670. The User Manual describes in detail how to replace the tubes, making it quick and easy.