The amplifier didn't make life easy for me once it turned on for the first time.  As you can see in this thread there were some initial problems.  To make a long story short, there was a bad diode that was throwing everything off.  Once this was corrected, all ran perfectly fine.  However, using alligator clips to hook everything up definitely changed the performance of the amp.  DC offset was 8v with alligator clips, and 0.07v hard-wired.  So, if you have a problem with alligator clips, just hook it up direct, it could just be the poor junctions.

After the amp was finally brought up and hard-wired, it has another issue.  There was a bad zener diode that was causing the amp to act up.  This was later realized, fixed, and the amp worked again.  However, the problems continue!

It seemed that the aluminum plate on the PCB was a good idea, but not completely.  Aluminum does an OK job for RFI shielding, but a poor job at magnetic and inductive shielding.  So, there was some humming and high noise floor on the amp.  After hours of reworking to get a steel plate underneath the PCB, there was still hum!  It turns out, it was my grounding configuration instead.  I had a small jumper wire that connected the ground plane on my cap bank to my star ground.  This was creating the hum.  Once that was fixed, all was good, or so I thought.

After the hum was gone, I tested out the amp.  All seemed to work fine.  I went to bed and put the project to rest.  When I got up the next day, excited about the new amp, I fired up a speaker and started to listen (test speakers thankfully).  After a few minutes, the amp was around 60 degrees C, and the speaker started smoking.  After a lot of cursing and throwing things, I sought some answers on the DIYaudio forum.  After 8 pages and 73 posts, It was determined that I had two transistors in backwards.  I was using two different types, each mounted opposite of eachother.  I was confused which I was using and had them reversed.

In the process of figuring this simple fact out, I broke 3 traces off the PCB, thought I had an oscillation issue (which I very well could have had, I fixed it just in case), and wasted around 20 hours.  All in all, I learned two things:  I need a scope, I need a variac.

For future, if anyone is reading this and is building their own Aleph3, keep some of these things in mind.  With this circuit, just because its running and playing music, does NOT mean its working.  It is actually a pretty bullet-proof design and is very difficult to have it NOT play music.  I had a ground issue, and oscillation issue, and a pair of transistors inserted wrong and it still seemed to work. 

Testing at low volumes is worthless.  In all cases where I thought things were fixed, I was testing at very low volumes.  In each event, things appeared to work fine.  It turns out, the DC was just so low it didn't hurt the speaker.  Also, in one of my cases, I wasn't getting any gain.  So, that was the loudest it actually went!  Don't be afraid to crank it up.  This will aid in testing.

A dummy load is a great little tool to have.  It acted just like a speaker and allowed me to "load" the amp without worrying about blowing anything.  I hooked a dummy load up to a little panel meter that has some leads off of it.  This allows me to visually see the amp working (like a VU meter), and to hook up a meter to measure DC, AC, etc... 

Another little lesson I did not know was that the leads on a PCB are pretty sensitive.  Soldering and desoldering them multiple times takes a toll.  If you are doing multiple solder jobs on a board, be very careful.  And if you are already frustrated because things haven't been working out, maybe its not a good idea to desolder a board.  I did this and in my haste broke a few traces.

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