Hi all just a few questions from a beginner:

Project: Soldering (soic – LM4562MA) on a computer sound card (replacing a few chips) :

1. Is the Kester .015” solder that is sold here at this site more than adequate to use for this project?

2. Can I use a more exotic solder such as ones with 4% silver for better results?

3. Are the solder usage interchangable or is the 4% silver used for specific soldering only?

Thank you in advance. More question to come :P

I’m very skeptical that silver solder will have any noticeable impact on your sound card. I haven’t done any controlled studies to prove this, but I also haven’t found any studies showing improvements the other way (that it is better), only qualitative praise from people selling silver solder—no hard numbers. The increase in conductivity from the silver and the small distance over which it applies leads me to hedge my bets towards silver solder having little to no measurable effect. Others have had this same debate
and also haven’t produced any hard numbers.

The following is from our intro soldering guide guide:

(About silver solder), People claim that it flows better, has a lower melting point, is stronger, and has a higher conductivity. According to Indium’s solder wire data sheet, their 2% silver solder has an electrical conductivity that is 11.9% of Cu compared to 11.5% of 63/37 tin-lead solder, a shear strength of 7540psi vs. 6200psi, and a tensile strength of 7000psi vs. 7500psi for 63/37. So, yes, the claims are true, and also mostly insignificant. Silver was initially added to solder to prevent silver platings on component leads from dissolving into the solder (“silver migration”) and forming brittle joints. Having silver in the solder reduces migration, so you may want to use it on silver joints.

This is all probably way more than you wanted, but the long and short of it is that silver wasn’t originally added for audiophiles (read this Qualitek brochure ), and the increase in conductivity is awfully small. I suspect that there would be more of an effect from flux residue, so my advice is just to clean the joints thoroughly with alcohol after soldering (although it’s debatable whether even this is necessary).

You’ll probably be OK with just about any solder :)