Retro Instruments OP-6 Single Channel Tube Microphone Preamp

The Retro Instruments OP-6 has been the behind-the-scenes ‘Holy Grail’ tube preamplifier for ribbon microphones for well over 60 years. Its almost endless headroom and gain are legendary, as is the extremely thick, rich tone imparted by its unique design. The OP-6 was used on some of the greatest recordings of the past, and many of these coveted units are still in use today. Unfortunately, these days originals are hard to find, are very expensive, and mostly don’t perform to the technical specification they once did.

The vintage unit’s feature set is also somewhat limited when compared to modern standards. While the preamp sounds just amazing on ribbon mics –or any other microphone type for that matter – with each pairing an adjustment to the input transformer (inside the unit) is required to a