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.
Key features:
- Classic 550b Equalizer design
- Two range switches to individually alter gain steps
- Usable as a 550b, 550D or 550M
- True hardwire bypass
- Balanced In & Out on XLR
- Unbalanced input on 1/4"
- EQ In/Out switch
Got questions?
Head to our contact page or give us a call on 02 9449 8487 and our friendly team will be able to assist you.
