API 550a

500 Series 3-Band Equalizer


API-550a-TightManufacturer: API
550a 500 Series 3-Band Equalizer
Retail: $1195 USD
Street: $1015.75 USD
Category: Analog Outboard
Our Description: The API 550A is a 500 series three band equalizer that is versatile and wonderful sounding. It has that great classic API sound that adds punch and clarity to any instrument. It is a semi-parametric equalizer giving you control over the frequency and gain with API’s classic concentric knobs. There aren’t many frequency choices, but the ones that they have given all sound great.

Level – Professional
Features – Just What You Need
Ease-of-Use – Average
Sound Quality – Sounds Amazing
Reliability – Works Every Time
Bang-For-The-Buck – You Get What You Pay For
Build Quality – Excellently Put Together

Manufacturer Description: Manufacturer Description: Few equalizers enjoy the respect and admiration of the coveted API 550A. Designed by the now legendary Saul Walker in the late 60’s, the discrete 550A was first used as a modular OEM equalizer. As the industry rapidly embraced the sonic quality of the 550A, it quickly found it’s way into many custom console designs by Frank DeMedio and other leading engineers. Many of these consoles are still in use today.

* 3 bands of classic API equalization
* Each band offers 5 API selected frequency centers
* Reciprocal and repeatable filtering
* maximum 12 dB of boost/cut per band
* EQ Band 1 and 3 offer shelf/peak switching
* “Proportional Q” narrows filter Q at extremes
* Traditional API fully discrete circuit design
* High headroom +30 dB clip level

Forty years later, the 550A remains the standard against which other EQ’s are measured, and it has played a major role in the recording industry for decades. Still copied but never duplicated, the 550A became API’s standard channel module EQ when the company began manufacturing consoles in 1971. With virtually all existing units spoken for, popular demand for this EQ resulted in API finally resuming production in 2004.

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