API / 550b

This is a 4-band equalizer module from API. Each band can be boosted or cut by up to 12dB. It features API's traditional fully discrete circuit design.

[直輸入品][Direct Import]

■4-Band Equalizer Module
■A 4-band version of the most popular 550A
■Equipped with a 7-position center frequency selector switch for each band
■Reciprocal and continuously controllable filter function
■Up to 12dB boost/cut for each band
■Range control with ""Proportional Q"" circuitry
■API's traditional fully discrete circuit design
■High headroom with a clipping level of 30dB

The 550EQ was a staple in American recording history throughout the 1960s and 1970s.

Originally conceived for use in API consoles, this latest 550 ""B"" version inherits the potential of the 1967 ""550"" and subsequent ""550A"" models, while adding an additional band for wider frequency range.

Incorporating API's discrete circuitry and original components (API 2520 op amps), the 550B blends past and present technology.

While many modern equalizers tend to be complex, the 550B provides engineers with the simplicity of functionality found on its control panel.
In other words, because only a select number of functions are available, all of them are useful to the engineer.
The 550B's effectively divided four-band control is extremely useful for various troubleshooting and audio sweetening applications.
Each band has a seven-position frequency selector switch, covering a range of four to five octaves.
This specification was determined through rigorous research with many renowned engineers.
Of course, the underlying design faithfully reflects the design and specifications of the original model.
By adopting the ""proportional Q"" design proposed by API in the 1960s, the 550B allows control of a wide frequency range with just a few settings.
This eliminates the need for a bandwidth parameter.
This feature minimizes phase shift, a problem with many equalizers.
Thanks to this simple operation, the 550B also makes it easy for users to return to their original settings. The superiority of the 550B is clear to engineers who actively use equalizers.
Whether used effectively or for correction, the 550B's performance will hit the spot for any engineer.
When significant tone control is required, the ample headroom provided by the original 2520 op-amp allows for sound creation that takes full advantage of the benefits of analog processing.