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Spur07
07-03-2011, 09:39
Hi guys

Quick question if may, I'm aware of the practice of re-capping an old amp to bring it back up to original spec, but what effect does re-soldering an amp have?

I recently purchased an old 70's amp and someone who knows this type of amp well has recommended I service the solder after I mentioned the bass is indistinct and soft. He reckons the solder gets dry and it affects the resistance.

Has anyone got an opinion on this? please forgive my ignorance :scratch:

Ta

Techno Commander
07-03-2011, 09:55
There is a possibility of getting dry joints (poor contact). Especially if there are any "sub boards" or large components attached to the main PCB. Usual practice is to reflow these joints. Replacing the solder isnt required. A visual inspection will reveal any bad joints.

As well as replacing caps, if there are any adjustable resistors (usually used for setting bias current) these are also worthwhile replacing.

Rare Bird
07-03-2011, 10:15
Just make sure you have the specs to reset them.

Well my amps knocking on 42 years old had a total rebuild, & boy did it need it... every single part on the boards were replaced hence every solder joint replaced, it's like night & day, the only solder i will ever use is 'Wonder Solder' it flows like a dream & at low temprature (which is important imho), excellent reliable joints.I do recommend this solder if you are new to Soldering as it's very easy to use. You should completely remove any old solder tho by solder sucker before re applying new to avoid compromising the quality of such solder.