Locomotive Audio 40AM-2

The Locomotive Audio MODEL 40AM-2 is a meticulously crafted, 1940s-inspired stereo octal tube preamp that combines vintage circuitry, premium components, and innovative features to deliver a thick, warm, and harmonically rich sound, complete with adjustable tonal shaping, high-impedance DI input, transformer windings, and a five-position response control for maximum versatility in professional audio applications.

A Vintage-Inspired Masterpiece

Drawing from legendary designs such as the RCA BA-11A and Gates SA-70, the 40AM-2 blends iconic elements of American tube preamps into a single unit. It produces the dense, saturated sound synonymous with the golden age of recording while offering modern functionality for contemporary studios. This hybrid design provides users with a comprehensive toolset to achieve the characteristic warmth, depth, and compression of 1940s tube gain stages.

Precision Features for Tailored Sound

The 40AM-2 incorporates a host of features that allow users to sculpt their audio with precision. It boasts two premium in-house wound MuMetal shielded input transformers and nickel-steel output transformers, which contribute to its rich tonal character. The dual 6SJ7 octal tubes amplify signals with a maximum gain of 52 dB, utilising one as a pentode and the other as a triode to create a dynamic, layered sound.

The input knob enables a five-position selection of transformer windings, allowing adjustments to the frequency response and input gain for both mic and line modes. Each setting subtly alters the tone, providing additional gain when needed and ensuring optimal signal transfer to the tube stage. The response knob offers another five-position rotary control, enabling users to shape the tonal balance and harmonic footprint. Whether enhancing lows and highs for a punchy, expansive sound or emphasising mids for a more focused, vintage tone, the response switch delivers unparalleled flexibility.

For added convenience and control, the level knob adjusts the signal output while interacting with the response settings to achieve the desired tonal balance. Users can easily fine-tune the output to match other equipment, making the 40AM-2 a seamless addition to any studio setup.

Modern Features Meet Vintage Character

The 40AM-2 goes beyond vintage replication by integrating features designed for contemporary workflows. Its high-impedance direct input (DI) makes it ideal for capturing the nuanced tones of instruments like electric guitars and basses. A 20 dB pad and an 85 Hz low-cut filter expand its utility by offering greater control over dynamic range and managing low-frequency rumble. The line mode, complete with dedicated XLR connectors, prevents phantom power from interfering with external audio sources, ensuring a clean and reliable signal path.

Crafting the 40AM-2 Sound

The unique combination of vintage circuits and modern innovation gives the 40AM-2 its distinct sonic identity. By merging the pentode input of the RCA BA-11A with the triode feedback structure of the Gates SA-70, this preamp achieves a lush, compressed sound reminiscent of its predecessors. These design elements make the 40AM-2 a powerful counterpart to its 86B and WT-72 siblings, creating a family of tools that complement each other perfectly.

A Creative Catalyst

The Locomotive Audio MODEL 40AM-2 is more than just a preamp; it’s an instrument for creative expression. By offering an array of tonal options, it allows engineers and producers to experiment and refine their sound to perfection. From its tonal shaping capabilities to its detailed harmonic response, the 40AM-2 is designed to inspire and enhance the recording process.

Lifetime Assurance

Built with precision and care, the 40AM-2 is backed by a lifetime warranty, reflecting Locomotive Audio’s commitment to quality and reliability. Professionals can invest with confidence, knowing this piece of hardware will perform flawlessly for years to come.

• Two octal 6SJ7 tubes providing 52 dB max gain, with one as a pentode and one as a triode.
• Five-position input transformer winding selector for tailored mic and line input configurations.
• Five-position response knob for shaping tonal balance and harmonic footprint.
• High-impedance DI input, 20 dB pad, and 85 Hz low-cut filter for enhanced versatility.
• Premium in-house wound MuMetal shielded input and nickel-steel output transformers.
• Line mode with dedicated XLR connectors to prevent phantom power interference.
• Robust build quality backed by a lifetime warranty for professional reliability.

This item, like everything we supply, comes with the complete support of our expert team. Our excellent technicians have been specifying, building and supporting studios for over twenty years. If you have any problems with installation, setup or everyday use, they’re never more than a click away, and always happy to help.

You can contact them here.