I had to finish the testing of the prototype 833A output transformer in a hurry. I spent two hours trying to blow the 833A prototype amp up by playing guitar through it at extreme volume levels, complete with feedback and hard clipping. No dice, the amp just kept putting up with my S***, although I did blow the bench circuit breaker twice. I started a new 833A page to present these results. There are pictures and some data from an 833A amp that was temporarily assembled to test a prototype output transformer. The amp took up all of one work bench, and part of another. I put it together in a big hurry (3 hours) and it shows. I got over 200 Watts RMS from this thing, and it took some ridiculous abuse without complaint. All good things must come to an end, and this is no exception. I have already disassembled the amp.
The revised SE amp instructions are finished and an amp is being built currently. I will be out of town for most of August. The SEamp boards will be offered for sale when I return. This will be in early September. I will be working a zillion hours a week before I leave so this might be the last update for a while.
I was asked, " Why did you need to rewrite the manual. Was it too hard to follow?" No the manual was (and still is) easy to follow. The original test and adjustment procedure required making voltage measurements on a live board, and simultaneously adjusting the bias. This is no problem for an experienced builder, the original target user. It became apparent that many inexperienced people wanted this amp. I worked with two of the early consumers to devise a test and adjustment procedure that first timers are comfortable with. This is the multiple meter method outlined on the safe meter use page. This procedure separates the user from the electricity, making the procedure safe for newbies and experienced users alike. Now that digital meters are as cheap as screwdrivers, there is no reason not to have a few.