Datasheet

5500

Stereo/Dual Mono 550

EQs with Range Switch

5500

Stereo / Dual Mono 550 EQs with Range Switch

Features:

 Classic 550b Equalizer design

 Two range switches to individually alter gain steps

 Useable as a 550b, 550D or 550M

 Peak/shelf switch on Hi and Lo bands

 True hardwire bypass

 Balanced In and Out on XLR

 Unbalanced input on 1/4"

 EQ In/Out switch

The beginnings of the 5500 circuit can be traced back to the original 550 equalizer designed by

Saul Walker, the founder of Automated Processes Inc. The 550 was designed as a console

equalizer, which uses an unbalanced input due to the architecture of the recording console.

Because the ergonomics of a console dictate that the controls take up little space, sometimes

the number of included functions can be limited. The 5500 is specifically designed to address

these limitations; it has a balanced input, a true straight-wire bypass, an integrated power

supply with noiseless muting and a range control that expands its versatility to mastering

applications.

Typical of API products, the 5500 contains no integrated circuits in its signal path. The gain

comes from two hand-built 2520 Operational Amplifiers in each channel. The balanced input is

handled by a 2510 Discrete Operational Amplifier, which is similar to the 2520, but without the

high-current output stage. A key component of the API sound, the 2520 coupled with the API

2503 output transformer, is capable of delivering +30dBm before clipping.

An extremely useful feature in the 5500 is the range control. The range of the amplitude

controls can be reduced to 1/2 or 1/4 of their stated scale, providing a means to adjust the

tonal balance with finer resolution in an even gentler manner. This is especially useful for

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5500 Stereo/Dual Mono 550 EQs with Range Switch 5500 Stereo / Dual Mono 550 EQs with Range Switch Features:         Classic 550b Equalizer design Two range switches to individually alter gain steps Useable as a 550b, 550D or 550M Peak/shelf switch on Hi and Lo bands True hardwire bypass Balanced In and Out on XLR Unbalanced input on 1/4" EQ In/Out switch The beginnings of the 5500 circuit can be traced back to the original 550 equalizer designed by Saul Walker, the founder of Automated Processes
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5500 Stereo/Dual Mono 550 EQs with Range Switch complex program material as contained in stems or submixes and is ideally suited for mastering purposes. API’s 5500 also features a true hard-wire bypass which wires the output connector directly to the input. Shortly after the power is first applied, or immediately after it is lost, a special circuit enables “bypass mode” so that power thumps are never heard. The 5500’s input XLR is connected to an active balanced circuit.