MXL 991 Mods
The MXL 991 is an inexpensive pencil condenser with a few significant barriers to great performance.
The small-diaphragm capsule is hit-or-miss; some sound good, but most do not.
The other problem is that the circuit is built with inexpensive and indifferently-selected parts, resulting in mediocre performance.
Fortunately for MXL 991 owners, we have replacement solutions for both the circuit and the capsule in this mic, which give the 991 performane on a par with European SDCs costing 5-10 times more.
These premium small-diaphragm condenser capsules are available in both Cardioid and Omni varieties. We developed them to provide MXL SDC mic owners with an easy and significant sonic upgrade.
Our Cardioid capsule is voiced with a relatively flat frequency response. This allows the capsule to complement a wider variety of sources. Whereas most MXL SDC capsules have attenuated bass, a 5dB drop around 4–6kHz, and a boost around 15kHz, we created a capsule that is full and rich sounding across the sonic spectrum.
These capsules can be installed onto the MXL 991 without tools. They work nicely with the stock circuit (and they work even better with our custom Schoeps replacement circuit; see below).
Transformerless SDC 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.