Suncalc wrote:
I have to agree with Miguel on that score. The KT88 is the same tube as the 6550 power tube and they make for amazing amps. You could even build a stereo triode strapped KT88 PP class AB1 amp and still get 30w per channel
and have an all triode signal chain. The Edcor XPWR016-120 has the voltage and current required and even has a 70 bias winding.
Now for the important question. Exactly how much money

do you have to sink into the project? I'm sure people will suggest all manner of possibilities however, in the end, your limiting factor may well be your budget. Does this need to be a $250 type of amp or a $1000 type of amp? Or maybe somewhere in between? It also depends on how sensitive are the speakers. If they need 20W or 25W to really get rolling then a single ended amp is probably out of the question. If they sound good and produce enough volume at 8W or 10W then a SE amp would probably be a good choice.
You did say that you'd like to build an SE amp. In single ended operation the KT88 can deliver up to 20W but the distortion is a little high (13% - Ds=0.68%/W). If you drop the output power you can get 12.5W with a more acceptable 7% distortion at full output (mostly second harmonic - Ds=0.56%/W). The 6L6 will give you about 11W in single ended operation but the distortion is 15% (Ds=1.36%/W).
So the questions you need to ponder are:
1 - How much power is really required to drive these speakers?
2 - How much money are you willing to spend on the project?
3 - How complicated a project do you feel comfortable doing?
4 - Are you committed to an SE design or are you willing to consider something like an oddwatt where there are lots of people with all kinds of experience to answer questions?
Answer these questions and you'll be much farther along in making a decision about what project to build.

Ok here are my answers, hehe:
1. 25W is the highest/maximum rating to drive the speakers at full volume. They used to hook up to a stereo system i once had, but I cannot remember its output unfortunately. I have 2 of them, and I would like to use them with a stereo tube amplifier if possible.
2. My budget is not very high, so I was thinking around the 200-300 dollar range. If that is even possible
3. I want one that will allow me to learn easily. I guess im not a novice, but im not an expert... I guess somewhere around intermediate. I want to do one that is complicated, but not overly complicated where only a licensed engineer can handle(Plus I dont know much about inductors, which ive been trying to understand. Random i know, but i guess it kind of shows how much i know...).
4. I dont know much about what a SE tube amp is or an oddwatt. I know that oddwatt is a company that sells kits(It cant be a kit, i have to build it straight from a schematic to get a grade.). And is a single ended tube amp just mono?
I guess maybe i still am quite a notice at this kind of stuff...