Grimm Audio MP1 Power Supply for Tube Microphone

Even if the power supply on your vintage microphone is still functioning, the MP1 s stable power and exceptionally low noise floor can give you significantly improved sonic results and voltage settings are customized at the factory for optimal performance with your microphone model. The unit offers discrete voltage regulators, a shunt regulator for the anode supply and a high precision series one for the filament supply. The anode supply offers a noise floor as low as -100 dBV, which, on average, is 20 dB better than existing supplies, while the shunt design turns the regulator into an active decoupling device, eliminating electrolytics.

The MP1 includes a detachable foot and multipin XLR cable that you can attach to your existing microphone cable.

Voltages for the MP1 are factory-set to optimize performance. Please call us when ordering to customize the settings for your microphone.

How It Works

• In many classic mics, the heater voltage is also used to bias the grid of the amplifying tube in the microphone, implicating an open gateway from the heater supply to the sensitive input of the mic’s amplifying stage. Grimm therefore chose to design a clean and ultralow-noise discrete voltage regulator for the heater supply as well. It features a very low drift to ensure the heater voltage always remains within specs.
• The MP1 features a specially designed discrete shunt high-voltage regulator fed from a current source to maximize suppression from mains-induced anomalies. It also offers very low noise (typically -96 dBV or 16 uV at 20 to 20,000 Hz unweighted). More importantly, this shunt supply sounds more natural than the more commonly used modern series regulators, due to the absence of electrolytic capacitors at the output.
• Both the high-voltage and the heater supplies have an extra crowbar protection circuit that will switch on in case one of the supplies breaks down. This is an extra line of defense to protect the valuable tube in your microphone.