My First Tube Amp Project S5 K-12G

[Delta Steve]

After much consideration and cost constrainments, this amp looked like a good first project. I've just started and I have the board almost finished. I substituted
Solon 22uf caps for the caps that came with the kit. I am also going to do some other mods that other people have done. I have most of the parts I need to finish. I will post Pictures as I go and I may have some question ask

[oldschooltube]

Good choice for a first tube project. I like the S5 kits because they have a god PCB layout and decent instructions and leave tons of room for tweaking later on. I built the 16LS kit as my first project and still love it. IMHO however, I would take the stock output transformers and throw them in the trash. These stockers are puny and the worst link in the whole system. They area also terribly saggy on the low end. Pay the extra cash and get a set of Edcor transformers and you will not be sorry! I would say that is the best mod I have done to my kit. I also replaced the rectifier chip with twin diode tubes for a nice slow start on the B+ and all the coupling caps are now Orange Drops.

[Delta Steve]

Originally Posted by oldschooltube

Good choice for a first tube project. I like the S5 kits because they have a god PCB layout and decent instructions and leave tons of room for tweaking later on. I built the 16LS kit as my first project and still love it. IMHO however, I would take the stock output transformers and throw them in the trash. These stockers are puny and the worst link in the whole system. They area also terribly saggy on the low end. Pay the extra cash and get a set of Edcor transformers and you will not be sorry! I would say that is the best mod I have done to my kit. I also replaced the rectifier chip with twin diode tubes for a nice slow start on the B+ and all the coupling caps are now Orange Drops.

Nice amp thanks for the input. I am doing some tweaking. I am using Solen caps for the coupling caps and putting snubbers on the heaters also changing out the bridge rectifier with fast recovery diodes. I will go on from there

[Soonerorlater]

Hi Delta Steve,

I built the K502, an amp very similar to your own except it uses the 11BM8 tubes. Made all the tweaks ( coupling capacitors are Auricaps ) including upgrading the output xformers. This made the most noticable difference imho. I wanted Edcors but I got a good deal on Hammonds so I went for them instead. Often wonder how the Edcors would have sounded.


brgds Bill