...

Part 1: The road to the UpX-4 (2011)

by John Paul Chacha on Wed, 5th Sep 2018. Read 154 times.

The year is 2011 and I'm building the amplifier to rule them all. It's called the UpX-4 Multimedia Utility Amplifier and it's based on my “pump-mode amplifier” configuration.

The Build


The amplifier is made up of a low-power section called the UP-Core and a high-power section called the UP-Pump. The next two images show the core being put together. I had to do this three times before I finally got it right (the other iterations were unstable).  


 


  A big amp required a big transformer and beefy transistors. After a lot of experimentation which may or may not have included driving the transistors to their maximum ratings, I finally settled on the RCA TO3 transistors (I don't remember the part number, but they're rated at 160 VCEO and 16 A IC.


 


  8mm of glowing perspex for the looks...


  Construction of the pump section. I use acive droppers – expensive but very effective. I suspect that I'm the only person on earth who does that.


 


 


 


  Input module.


  All the compnents mounted and ready to go.


 
Here's the final product: