I use this stuff: Cardas Soldering Wire Quad Eutectic Silver Solder with rosin flux. Expensive, but should help lower chances of a cold solder joint. I just started on my third 1/4 lb spool. I can't remember the last time I had a cold solder joint (although I think my solder technique is decent).
I did use the cheaper Kester (can't remember which formulation) when I built my tube amps. I used a lot of solder in those (probably too much), and didn't want to use the expensive solder. But I also figured I was working with fairly large surfaces (wires, component leads, turrets, etc), so the work itself was somewhat easier.
I did use the cheaper Kester (can't remember which formulation) when I built my tube amps. I used a lot of solder in those (probably too much), and didn't want to use the expensive solder. But I also figured I was working with fairly large surfaces (wires, component leads, turrets, etc), so the work itself was somewhat easier.