Beloved by top engineers and producers, the Stam Stamchild SA-670 has become a modern classic. The Stam Stamchild SA-670 was designed to match the original’s audio path, transformers, and tone while remaining affordable.
Using premium transformers from AMI (US) and Sowter (UK), along with sixteen matched NOS 6BA6 tubes per channel and two 12AU7 tubes in the control amplifier, it faithfully replicates the original’s sound.
To reduce manufacturing costs without compromising audio quality, a solid-state power supply replaced the original tube-based design, and a hybrid sidechain was introduced to maintain the vintage tube character of the control amplifier while preserving the original Fairchild 670’s DC threshold settings.
Like the original, the Stamchild-670 features two independent limiters in one unit, capable of processing stereo signals or mid/side components through a matrixing network.
The unit uses eight custom transformers, including AMI-made replicas of UTC A-26 input transformers for smooth clarity and hefty low-end saturation, and Sowter-made HS-52 replicas for the output. Additional autoformers and toroidal transformers provide reliable power at both 115V and 230V.
The Stam Stamchild SA-670 includes a lifetime supply of 6BA6 tubes, ensuring consistent performance. These tubes replicate the extinct 6368 tubes in pairs, while the 12AU7 tubes manage the control amp.
Additional features enhance its usability for modern studios. An AGC filter offers four sidechain options: full-band, 90 Hz high-pass, 180 Hz high-pass, and a mid-range filter with both 180 Hz HPF and 3 kHz LPF.
A stereo master output attenuator allows for pushing the tube stage for added harmonic colour without clipping. The dry/wet control enables parallel compression in 10% steps, providing versatility for mix and mastering sessions.
