Grace Design M501

From the m101 to the m501: the same philosophy, adapted for modular racks

The Grace Design m501 is the 500 series version of the m101 microphone preamplifier, known for its neutral reproduction and clarity. The goal remains the same: when the source is good, the microphone is well chosen and well placed, the preamp should not "impose" a signature but transmit the information with precision. In a modern environment where 500 series racks allow you to build a custom signal chain, the m501 brings this high-fidelity approach in a compact module, easy to integrate into a recording or reamping/DI setup.

A preamp for demanding recordings, from home studios to professional studios

If you are looking for a "musical" microphone preamplifier without aggressive magnification effects or artificial coloration, the m501 is an excellent choice for vocals, acoustic instruments, ensemble recordings, overheads, strings, or any situation where dynamics and timbre must remain natural. Its substantial gain reserve also facilitates working with low-output dynamic microphones, while the ribbon mode secures the use of vintage or modern ribbon microphones. Finally, the Hi-Z input allows direct recording of bass or guitar, with appropriate impedance and reliable relay switching.

Transparency, control, and innovations serving the recording process

Fast and stable design made to keep the signal intact

The m501 is based on a transformerless symmetrical design and a trans-impedance amplifier architecture, designed to respond quickly to transients and maintain a clean sonic image. The choice of high-quality metal film resistors (0.5% tolerance) in the audio path aligns with this goal: minimizing variations, reducing noise, and maintaining tonal coherence from one take to another.

Precise gain and studio ergonomics

Compared to a continuous potentiometer approach, the new 12-position rotary gain selector with gold contacts promotes reproducibility (session recalls, easier stereo matching) and a more "measurement instrument" feel. Add to this a high-performance line output stage and a high-level high-pass filter amplifier: the module stays clean even when pushing gain or when the session demands a wide dynamic range.

Ribbon mode: more than just protection, a real recording tool

The mode dedicated to ribbon microphones does more than just cut phantom power: it increases input impedance and bypasses the phantom power coupling capacitors via relay, while making 48 V phantom power activation impossible. Result: you protect the microphone and also optimize compatibility with certain dynamic or ribbon microphones that appreciate a higher load, for more stable low end and a more natural "breathing" sensation.

Less interference, more confidence

In the studio as well as in dense installations (multiple power supplies, lighting, networks, RF), the enhanced HF interference suppression helps maintain a clean noise floor. With its LED indicators (phantom power, ribbon mode, high-pass filter) and black anodized front panel with laser etching, the m501 is designed for intensive daily use.

• Five-year warranty on parts and labor

Technical specifications

Category

microphone preamp

Format	500 Series module (modular version of the m101 microphone preamplifier)	High-pass filter	75 Hz
Phantom power	48 V	Specific mode for ribbon microphones (also excellent for dynamic microphones)	phantom power decoupling capacitors bypassed by relay, higher input impedance, and 48 V phantom power cannot be activated
Design	transformerless balanced	Instrument input	direct high-impedance (Hi-Z), 1/4" jack
Amplifier circuit architecture	transimpedance	Switching relay to the Hi-Z input	sealed, gold contacts
Audio path resistors	metal film, 0.5% tolerance	Three output connectors	balanced XLR, balanced 1/4" stereo jack and unbalanced 1/4" mono jack
Gain range	10 to 75 dB	LED indicators	48 V phantom power, ribbon microphone mode, high-pass filter
Gain selector	rotary, 12 positions, gold contacts	Country of manufacture	USA
Output stage	line