The API 535-LA can both amplify and attenuate incoming and outgoing signals for ultimate flexibility-all while providing API's trademark warmth and tone.
The 535 excels at adding warmth to a variety of signals. Recommended uses include:
Warm up digital signals of all kindsAdd Tone to Keyboard rigsAdd warmth to any mix
Audio playback devices, mic preamps, or audio processing devices that do not have their own level control will also benefit from the added tone and control of the 535-LA.
The 535-LA also includes a balanced input, a polarity switch, a 20dB pad for incoming signal attenuation and a three position toggle switch, which allows for different output gain levels from the transformer. This is designed to drive long balanced lines with low distortion just as the 325 booster card does. Output gain range is from 6dB to 45dB. The 535 utilizes the discrete 2510 and 2520 Op-Amps along with API's proprietary transformers to create the unique, warm and reliable sound that API users expect.
Continuously variable detented input level trimPolarity button20dB Input PadCalibrated Level modeOutput Ratio selectorClip LED indicatorContinuously variable Output GainTraditional API fully discrete circuit designAudio circuit uses the famous 2510 and 2520 Op-AmpsTraditional API fully discrete circuit design
Frequency Response: -0, +0.2, 30Hz-20kHz
THD+N: .006% at factory CAL Level setting (+4dBu)
Noise floor: -85dBu at factory CAL Level setting
Gain Range: -inf. to 53dB
Maximum Input level: +32 dBu, balanced (with PAD)
Maximum Output level: +32 dBu MAX, balanced (1kHz)
Input Impedance: Greater than 20,000 ohms, ~4,000 ohms w/ pad
Output Impedance: Less than 75 ohms