Seventh Circle Audio A12B
API-style single-stage transformer mic preamp module
Preamp$339Manufacturer list price
Specifications
- Type
- Preamp
- Description
- API-style single-stage transformer mic preamp module
- Topology
- API-style single-stage transformer-coupled, discrete SC25 op-amp
- Signal path
- Analog
- Channels
- 1
- Channel format
- mono mic/line preamp
- Form factor
- module (SCA proprietary format)
- Connection
- SCA proprietary module format (CH02/PC01 chassis)
- DSP
- false
- Powered
- true
- Country of manufacture
- USA
- Phantom power
- 48V
Details
Controls: 12-position Grayhill stepped gain switch (15-70dB in 5dB steps), gain trim (up to 6dB cut), phase reverse switch, phantom power switch
I/O: Neutrik PC-mount XLR mic/line I/O; requires separately-ordered CH02-SP-A12 subpanel
Notes: Clones classic American (API-style) early-1970s single-stage transformer preamp design. CineMag CMMI-8-PCA input transformer (18dB step-up), CineMag CMOQ-2S output transformer standard (2L/2H nickel-core variants optional, +$45-65). Built-in discrete SC25 op-amp; site notes op-amp is non-modular so A12B ships assembled-module only (not sold as bare DIY circuit like other classic-series modules). SCA proprietary format -- fits SCA CH02/PC01 chassis only, NOT API 500-series (see A12-500 for that version).