Few interesting insights about the production and design approaches of the Sugden Audio high end audio products...

And So It Begins 

After all the circuit boards have been assembled and tested, it’s time to put the amplifier together. First assembly starts with fastening all the hardware to the chassis. This includes the mains socket, loudspeaker terminals and input sockets. It takes a bit of strength to ensure everything is nice and tight and care to make sure every socket lines up perfectly. The wires (tails) that have already been cut to length are then soldered to the hardware. Chris will have this Masterclass IA-4 built up for first test in about 5.5 Hours. After test it will then have the front panel and top fitted for final test and then an eight hour burn-in.


At the heart of every Sugden amplifier sits a mains transformer. The job of the transformer in simple terms is to receive the mains voltage and change it to provide power to various parts of the amplifier circuit with the required voltage and current. The transformer is probably the most important component in an amplifier because of the job it has to do. This is especially true in Sugden Class A amplifiers as they are running at full load all the time. All Sugden transformers are custom made to our exact specification and built for reliability, longevity and low noise.

Grande Cans 

The Grande power amplifier uses custom made 22000uf smoothing capacitors. These are a bigger version of those used in our Sapphire FBA-800 and provide excellent performance. The FBA-800 uses four multi emitter output devices per channel and this increases to twelve on the Grande, providing three times the current capability.

Gain Changer 

The Sapphire and Grande power amplifiers both have a front panel switch called 6dB Input Gain. This is a useful facility and allows better pre-amplifier, source and loudspeaker matching. Activating the switch will provide a 6dB drop in gain per channel giving a total of 12dB for both channels. Reducing the gain allows pre-amplifiers with a high output to have a more flexible and wider use of their volume control. Pre-amplifier and source component compatibility can also benefit, as well as high sensitivity loudspeakers.