Building SCA N72 Pre-amps

Seventh Circle Audio sell a range of kits to build high quality microphone pre-amps, and they rock. They come in several flavours, as single PCB modules that can be inserted into a custom chassis. I chose to build a couple of the N72 modules to begin with, which are based on the Neve BA183 modules found in the 1073, for example. Complete with Carnhill transformers, they have that instantly recognisable warmth of Neve gear, at a fraction of the price!

It took me about a day to build each pre-amp, and generally it went without a hitch, which is definitely testament to the quality of instructions and help on the SCA Forums. It’s best to practice your soldering technique on something less expensive first, if you’re not used to soldering with precision. It’s pretty easy once you get the hang of it.

Once you’re confident, start by stuffing the PCB with the lowest profile components first (resistors), and build up from there. You’ll generally find it easier to work with the board like this, since when you flip it over the parts are held in by the work surface, allowing you to mount most things flush for a more solid and professional looking board.

The only really tricky bit is wiring the input transformer, which involves soldering some resistor lead across certain pins as jumpers. Gravity is not your friend. Take your time, and all will be well.

How do they sound? Incredible. High quality pre-amps are essential to getting the most out of your microphones, but despite knowing this, I was still blown away by the results! They’ve got that warm bottom end that you’d expect from Neve gear, which isn’t to everyone’s taste, but they’re also really open in the top end, not dark at all.

I’ll definitely be building some of the other modules, probably a pair of each flavour once I can afford it.