MXL 603S Mods

The MXL 603S suffers from low-quality parts in the circuit, and overly bright capsules.

To correct these issues, we have released a wonderful circuit replacement kit that will not only give you a high-output, low-distortion, pristine signal path, but will also let you build a high-frequency rolloff into your mic's circuit to correct for a peaky/bright capsule.

Transformerless SDC Circuit Kit

transformerless circuit kit

We make our own custom 2-layer PCBs in the US, and provide a complete circuit's worth of handpicked and matched components. The result is linear from 20Hz–20kHz, with very low self-noise and distortion. It provides a full 60VDC to polarize the capsule.

Two build-time options are provided to allow personalization of the mic:

  • Pre-pad the mic by 6dB without adding capacitors. If you plan to use the microphone primarily on high SPL sources, use the included parts to cut the mic's sensitivity by 6dB via a noncapacitive pad option.
  • Roll off the highs to correct for an over-bright/peaky capsule, or as a darker mic for taming bright/thin sources.

Read more about the Transformerless SDC Circuit Kit.