API 550B — Equalizer
Fit and constraints
Intended use
Constraints
To use it
Questions
Which connections, drivers, operating systems, and sample rates are supported by this exact revision?
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What cables, mounts, power supplies, or licenses are included?
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Is the current retailer listing new stock, demo stock, open box, or special order?
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Description
The API 550B is a studio equalizer based on the original API 550 design from the late 1960s, featuring four overlapping EQ bands with seven switchable filter frequencies each. It incorporates API's proprietary 2520 Op Amp and employs Proportional Q technology, which automatically adjusts filter bandwidth based on gain settings to minimize phase shift. The unit draws from API's original specifications and adds an extra filter band with expanded frequency options.
Seller notes: API 550B — Equalizer. 550b.