[NelsonVandal]

OK, so now I've doubled the bias. Not the major improvement i was hoping for, but I'll give it some time. I just did a quick listening, and my tinnitus is bad today. The thing left to tweak is the output resistors (how bad can they be?, think I'll change them to 4,7 Ohm Koa's) and the input diodes. I think I'll try 1N4148. When I change diodes, I just as well add some input resistors.

The sound is quite good but there's a little bit of harshness or graininess, compared to my other amp, I wish I could get rid of.

 

[NelsonVandal]

I rolled the dual diodes for some 1N4148. The amp sounds even sweeter now. The sound is "fuller" and warmer, and it's less harsh. I'm not really sure if it was the increased bias or the new diodes that did it. I also added some 100k resistors in parallell with the 1,5k bias resistors on the + side. Now there's almost no DC-offset. The only original parts in the signal way are the output resistors.

Now it's almost the perfect portable for in-ears. I wish I had better IEM's than the Mylar3's. It's just not for in-ears, it plays so very sweet with my HD650.