The Fredenstein F660A Limiting Amplifier is a high-end valve compressor and limiter inspired by the legendary Fairchild 660 and 670, delivering the same very short signal path and sonic character but enhanced for modern audio production. Utilising the exact 6386 LGP tubes as the original Fairchild, four tubes per channel form a single-stage push-pull Class A amplifier. The minimalist signal path includes only a T-type input attenuator, input transformer, Class A amplifier, and a large output transformer, preserving the purity of the audio.
While the design philosophy echoes the Fairchild, the Fredenstein F660A introduces modern refinements. A DSP precisely controls tube operating points, ensuring consistent performance under all conditions. The side chain uses semi-conductor components to generate control voltages, further improving stability. The result is a compressor with the warmth and desirable compression style of the Fairchild, yet with extended frequency response, reduced noise, and lower distortion, making it ideal as a buss compressor in high-resolution audio environments.
The front panel of the Fredenstein F660A provides direct access to essential controls: Make-Up Gain, Compression Threshold, and Release Time. Six Release Time settings replicate the Fairchild’s original switchable modes, while the encoders also act as push buttons for functions such as Bypass, Sidechain High-Pass Filter, and Stereo Link.
Additional flexibility is provided with the Fredenstein F660A via the LCD screen, offering six Attack Time settings, metering options including RMS, Peak and Hold, as well as calibration modes. With 99 user presets, self-calibration, and repeatable exact calibration, the Fredenstein F660A is particularly suited to mastering applications.
By combining the tonal signature of the Fairchild with modern engineering precision, the Fredenstein F660A delivers the character engineers have always sought, without the drawbacks of vintage maintenance, loss of frequency content, or unreliable components. It offers the spirit of a classic design re-imagined for contemporary studios.
Features
- Modern update of the legendary Fairchild 660/670 compressor/limiter
- Features the same 6386-LGP tubes and short signal path as the original
- Modern DSP provides extended frequency response, lower noise, and less distortion than historic units
- Front panel LCD screen provides access to your most-used parameters
- Store up to 99 presets for easy repeatability
- Experience warm, natural sound via zero-negative-feedback design
- Fast attack time catches short transients for full limiting
- Adjustable DC threshold allows you to select between 0.5 and 5V
- Sidechain for avoiding compression in unwanted frequency ranges
- Self-calibrates for easy maintenance