API 565 Filter Bank

The API 565 Filter Bank is a versatile and precision tool designed for detailed signal shaping and problem solving in professional audio environments. Modelled after the legendary 215 filter section from API’s large format consoles, the API 565 retains the musicality and character of the original while adding modern control and flexibility.

It features fully sweepable high-pass and low-pass filters, each with selectable slopes. The high-pass filter ranges from 20Hz to 400Hz with −12dB or −18dB per octave slopes, while the low-pass filter spans 500Hz to 20kHz with −6dB or −12dB slopes. A powerful, variable notch filter is also included, offering sweepable frequency control from 20Hz to 20kHz and adjustable Q, allowing for precise removal of problem frequencies such as hum, resonance, or feedback.

Each filter section includes its own bypass switch for fast A/B comparison and flexible integration into any signal path. The 565 delivers high headroom with a transformer-balanced output capable of handling up to +28 dBu, ensuring clean and musical performance across a wide range of applications.

Built with API’s discrete 2510 and 2520 op-amps and the same transistor buffers used in the iconic 550 series EQs, the API 565 Filter Bank delivers the classic API sonic character with the control needed for both corrective and creative filtering tasks.

Features

• Sweepable low-pass filter (500Hz to 20kHz, -6 or -12dB slope)
• Sweepable high-pass filter (20Hz to 400Hz, -12 or -18dB slope)
• Variable notch filter with adjustable Q (fully sweepable between 20Hz and 20kHz)
• Individual bypass switches for each filter section
• Transformer Balanced Output to +28 dBu
• Uses API 2520 and 2510 Op-Amps as well as the same discrete transistor buffers used in the famous 550 series equalisers