This is a guide to building a F4 using my boards, but you may be able to find some useful information here even if you use other boards.

The boards are based on the schematics from Nelson Pass's FirstWatt F4. You can get the service/user manual here: First Watt: Products: F4

You might want to check out the GB thread here: http://www.diyaudio.com/forums/group...gb-f4-pcb.html

PCB
Here is a picture of the pcb.

There are still more available and you can order them from my site GB order page for cviller

Errata
There is a trace error around R22. I have cut the traces on most of the boards I have sent - and the rest of the batch will be cut before I send them out.

These are the cuts which needs to be made:


And the green lines indicate where a connection must be made:

This can be done...

As promised, I would make a guide to the boards and in particular to the additions I have made to the F5. I decided to do this in the blog, because then you can give me comments which I can use for improving the doc. However I'm not done at all, but I thought it would be nice to give you access to the BOM I have made.

IMPORTANT: Before you start stuffing your boards, you must read the manual/article written by Nelson Pass – available for download on the First Watt website (First Watt: Products: F5).

PCB
Here is a picture of the pcb.

There are no more boards available, but you can order F5 boards on the diyAudio store.


Schematics

Optionality
With the addition of optional extra output mosfets and cascoding, there are many possible ways to build the amp. Here I'll try to explain some of them.

Stock F5 example
Greens are populated and...