Tip o' the week - input jacks, Jack!
A common problem with vintage amps is a loose or dirty input jack. This problem often causes crackling or signal drop-out. It also sounds just like a bad mic cord, causing you to keep trying different cords in an attempt to get rid of the problem. The jack can be cleaned using a small brush designed for cleaning a .22 rifle bore. These brushes are available at most sporting-goods stores or anywhere that sells ammo, and are just a couple of bucks. They fit a standard 1/4" jack perfectly. Push the brush in and out of the jack a few times and you are done. It can make a big difference! Also, while you are at it, tighten the nut that holds the jack to the chassis. A socket wrench is best, but a small crescent-wrench will work if you are careful to not let it slip or mar the control panel.
Skip Simmons
