Recreating the finest tube compressor in history

The StamChild SA-670+ is an identical sounding replica of the most iconic tube compressor in history, the Fairchild 670. Hand crafted by our small team in Chile, the Stamchild 670+ is a fully discrete accurate sounding replica of not one but three different Fairchild 670’s with several added modern features. After carefully testing and measuring three original units we found that they all had a signicantly different top-end response so we decided to incroporate all three of them into the 670+ with a dark, dtandard and bright switch for each channel.

While developing this project we had two main objectives: first and foremost, the audio path had to remain as close as possible to the original units and secondly the compression curve had to be identical to the original. With this in mind we developed a few upgrades and carefully tested each component and its interaction with the circuit. After many months of research and tests we determined there was a way and so the StamChild SA-670+ was born.

With custom made transformers, 18 tubes, original VU meters, knobs and a state-of-the-art power supply, the StamChild 670 has the some tone, character, compression curves and frequency response as an old Fairchild compressor at a fraction of the cost.

“Tony Maseratti with the Stamchild 670”

The Tubes

The StamChild 670 uses sixteen 6BA6 and two 12AX7 NOS tubes. Being the single most important part of the circuit and heart of any Fairchild comp are the peculiar compression curves that can only be achieved with 6BA6’s and 6386 tubes. It’s peculiar time constants are what makes the 670 so unique. We have tested every tube configuration out in the market and always end up going back to matching NOS 6BA6’s for this task. Each pair of 16 6BA6’s is carefully matched for a smooth and optimal compression and burned for 72 hours to ensure they last decades to come.

In the rare event that a tube fails we have made sure to have several sets of tubes matched for each client to replace them at any given point and stock ourselves for a lifetime!

The Iron

We outsourced these transformers to several manufacturers and ended up settling with both the US-made AMI UT26 whom painstakingly recreated the timbre of the original UTC A26 input transformer as well as a huge Sowter 8344E for the output transformer. Thanks to their meticulous craftsmanship we can confidently say the Stamchild 670+ recreates every drop of character of the original and sounds indistinguishable from an original unit.

The Circuit and controls

The SA-670+ is not only an exact sounding replica of the original but it also adds several modern features to help with modern day productions. With these 10 added features the Stamchild 670+ is the most versatile, complete and mos accurate sounding replica on the market at a fraction of the original price.

• Three Fairchild 670’s frequency response selection
• Vintage and Modern mode
• Sidechain High-Pass filter
• Lat-Vert Link and Independent function
• DC threshold control (knee/ratio)
• Manual attack and release times
• Feedback/Feedforward compression
• Blend Control
• Output attenuation and make up gain
• True Bypass

Manufacturing

Each StamChild 670+ is handmade by a small team at our lab in Chile. To reduce the cost of manufacturing of these units we have made some modern implementations which do not affect the audio path and performance of the unit. We changed the tube-based power supply to a state-of-the-art solid state one which has no bearing on the sound.

With these measures we are able to bring the cost down while preserving the original tone without removing the character produced by the transformers and tube on the control amp and preserving the critical compression curves and timbre of the original.

Every unit is handmade and calibrated in our workshop in Chile where they get a full health check and are burned for 72 hours to ensure your Stamchild 670+ will last for decades to come.

Stam Audio Engineering products are about sound quality first and foremost. Every component of every unit is premium quality and carefully selected to ensure our units match or even surpass the quality of high-end boutique gear.

100% satisfaction guarantee – if you don’t love your StamChild SA-670+, we’ll refund you

If you’ve used an original Fairchild before, we’re extremely confident the StamChild SA-670+ will put a big smile on your face every time you use it. However if you’ve never touched the original before, as gear-lovers ourselves, we understand that the only way to really know if this compressor is for you, is to put it through its paces. That’s why the StamChild SA-670+ comes with a 30-day money back guarantee.

This allows you to get it into your rack and see how it impacts your recordings. If you love it (and we think you will!), great…keep the unit and create amazing music with it. If not, no problems. Just send it back to us and we’ll fully refund your purchase.

Fully Stepped Mastering Version is available per request.